Cooling System - mods run cooler

Post by **HenryJ** » Mon Jul 17, 2006 2:57 pm

We have had a week of 100+ temperatures and are looking forward to another week of the same. My truck has been doing really well in the hot weather.

I was going to post under one of the threads already out there, but I feel it is a combination that is working not just one mod or another.

I am running a Jet 180º thermostat , green antifreeze with a bottle of Redline water wetter , TransPro "extra capacity" radiator , LS1 electric fans , and a AD244 high output alternator.

The first change was to add the larger radiator. Around here in record heat , once the system was hot no amount of airflow would cool it back down. That was greatly improved after the addition of the new radiator.

Next step was to get a head start on cooling and not run quite so close to the edge. That is where a lower temperature thermostat comes in. I did have to relocate the IAT sensor in order to make the combination work. The 2001 PCM is just too tight to get away with it. That information is all in another thread - Relocating IAT

Now to match the cooling fan to the lowered operating temperatures. I was unable to find a clutch fan in other than the stock temperature. The stock fan really does a pretty good job, but locks in way to late. I opted to go with electric fans. In order to maximize the fans operation a bigger alternator is needed. The stock alternator is already working pretty hard. The addition of the electric fans is not what it needs. As heat builds the voltage drops and so does fan speed. Adding a bigger alternator helps in several ways. You maintain voltage to keep fan speed maximized, and it runs cooler since it is not having to work as hard.

There may have been some other mods that are contributing to the package. Such as a free flowing exhaust system. Modified front license plate mount area (cut out for flip down plate mount). Cowl induction hood lets the heat out at slow speeds and draws cool air at higher speeds. 2" body lift makes some room for the air to move out over the engine and transmission. Auxiliary transmission cooler helps to dissipate some of the heat to the airflow rather than the coolant. New radiator cap that doesn't allow air into the system. Restricted EGR system doesn't introduce as much hot gasses to the intake.

Some of these "small differences" may or may not affect the outcome. Lots of small changes can make a difference though.

My package seems to be working pretty well in a high desert environment.

What has been working for you?

2kwik4u · Post by **2kwik4u** » Mon Jul 17, 2006 3:59 pm

Sounds like a good setup, although I question the IAT mod.

The IAT in the stock system is a fueling sensor, and has no bearing on the cooling system at any level.

The rest of the mods most definately help though, and I'll be following 99% of the recipe in a year or two when the stock stuff no longer works, and the warranty period has expired.

Post by **HenryJ** » Mon Jul 17, 2006 4:09 pm

2kwik4u wrote:...I question the IAT mod.

The IAT in the stock system is a fueling sensor, and has no bearing on the cooling system at any level...

Oh, but it does. The PCM uses readings from the IAT and ECT to determine the amount of time to reach the preset threshold of 178º

killian96ss · Post by **killian96ss** » Mon Jul 17, 2006 6:33 pm

Is it possible both of you are right?

Yes, it is a fueling sensor. The PCM uses the air intake temperature to adjust the amount of fuel delivered to the engine (cold dense air = more fuel, hot thin air = less fuel).

I also remember Brule's trial and error with IAT positioning which helped cure the SES light problem after adding a larger radiator and e-fans. I believe the PCM was originally setting the SES light because it was taking too long to reach a preset temperature or threshold. After moving the IAT closer to the air filter it was reading about 20* cooler which prevented the PCM from setting the SES light.

Obviously the IAT has more than one purpose.

Steve

Post by **HenryJ** » Mon Jul 17, 2006 6:39 pm

Mine was not a trial and error solution. It was from research into the trouble code that was set.

GM data wrote:DTC P0128
Circuit Description

An engine coolant temperature (ECT) sensor monitors the temperature of the coolant. This input is used by the powertrain control module (PCM) for engine control and as an enabling criteria for some diagnostics.

The air flow coming into the engine is accumulated and used to determine if the engine has been driven within normal conditions. That is, conditions that would allow the engine coolant to heat up normally to the thermostat regulating temperature. If the coolant temperature does not increase normally or does not reach regulating temperature of the thermostat, problems with the diagnostics may occur. The diagnostics that use ECT as an enabling criteria, may not run when expected.

This diagnostic trouble code (DTC) will only run once per ignition cycle within the enabling conditions.

If engine coolant fails to reach a preset target temperature before a calculated air flow is accumulated DTC P0128 will set.
Conditions for Running the DTC
• DTCs P0100, P0101, P0103, P0110, P0111, P0112, P0113, P0117, P0118, P0125, P0500, P0501, P0503, P1114, or P1115 are not set.
• The coolant temperature is less than 81°C (178°F).
• The air intake temperature is -7°C (+19°F) or more.
• The engine is running more than 2 minutes and less than 17 minutes.
• The vehicle speed is more than 8 km/h (5 mph) for more than 0.8 km (0.5 mi).
• The mass air flow (MAF) average reading is more than 13 g/s.
Conditions for Setting the DTC

The length of time for the engine coolant to reach a preset temperature has been exceeded.
Action Taken When the DTC Sets

* The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
* The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC

* The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
* A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
* A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
* Clear the MIL and the DTC with a scan tool.

Diagnostic Aids
• DTC P0128 is designed to detect a faulty thermostat.
• A skewed ECT sensor may cause a DTC P0128 to set.
• A skewed IAT sensor may cause this DTC to set. The IAT sensor should read near ambient temperature with the engine running.

killian96ss · Post by **killian96ss** » Mon Jul 17, 2006 6:47 pm

Sorry, I thought you figured that one out on your own.

You shouldn't have said anything.

You could have had people believing that you have special powers which allow you to communicate with PCM's to find out what's really bothering them.

Steve

Post by **HenryJ** » Mon Jul 17, 2006 6:52 pm

I have been battling HAL for quite some time. Most of the time it gets the best of me. EFI live would be a nice thing to look into, but I just can't justify the expense at this point. It may not be able to alter the threashold anyway.

Autotap does offer some insight.

2kwik4u · Post by **2kwik4u** » Tue Jul 18, 2006 3:20 am

Had no idea there was an SES light for taking to long to reach a particular coolant temp.....I've never heard of, nor seen, nor read of that before.

Interesting info.

I sit corrected.

coffeedrnkr · Post by **coffeedrnkr** » Tue Jul 18, 2006 4:01 am

just another idea for releasing heat that I am looking at right now is putting in some hood louvers to release some heat out the top.

here are the ones I was thinking about getting

I was going to make them "real" though and actually cut a hole in my hood. I really wanted the real metal louvers but they are expensive off ebay and I didn't really find another source.

my biggest problem right now is that after all of the stuff I have done to my truck my clutch fan hangs like 7" below my radiator and I don't have a bottom shroud, so it is kinda worthless right now. it works for everything but suuper hot weather like this week

F9K9 · Post by **F9K9** » Tue Jul 18, 2006 4:02 am

2kwik4u wrote:Had no idea there was an SES light for taking to long to reach a particular coolant temp.....I've never heard of, nor seen, nor read of that before.....................

Yeah, I've thrown that code several times.

I've relocated the IAT next to the filter on the underside of my FIPK out of sight. I plug it back into the stock position before trips to the dealership.

Miles · Post by **Miles** » Sun Jul 23, 2006 7:07 am

Paul, be sure to check out these hood louvers from Race Ace:

That's what I plan to run.

1337vending · Post by **1337vending** » Sun Jul 23, 2006 11:50 am

HenryJ wrote: I have been battling HAL for quite some time. Most of the time it gets the best of me. EFI live would be a nice thing to look into, but I just can't justify the expense at this point. It may not be able to alter the threashold anyway.

Autotap does offer some insight.

Just a (tangent) idea, but there are provisions in the 2003 PCM for electric fans, which are just zeroed out since we have a mechanical fan. With EFILive and some wiring work it might be possible to have the PCM control your electric fans...that would be sweeet

Not to mention you can control all sorts of neat stuff like fan#1 and #2 turn on temps, and fan run-on time after you shut off the ignition to prevent heat soak. Very cool...I've used it on my 2004 GTO with great success

Post by **Walt** » Mon Jul 24, 2006 6:57 am

Has anyone thought about using an electric fan with a cowl induction hood? Could one be mounted to the hood and used to funnel air/heat out through the cowl?

F9K9 · Post by **F9K9** » Mon Jul 24, 2006 8:15 am

Walt wrote:Has anyone thought about using an electric fan with a cowl induction hood? Could one be mounted to the hood and used to funnel air/heat out through the cowl?

Interesting idea. It seems like it may work with a little sheet metal fabrication on the underside of the hood but, I question if, the results would be worth the effort.

I know I need to junk my stock hood insulation and do the mod that HJ did. I am having little luck locating it though.

I know, from when I was a K-9 handler, that popping the hood a little while out of my vehicle would make a dramatic difference in keeping the AC cold for the K-9 in very hot weather. Brule's mod and the hood louvers are ideas for one more piece of the overall heat puzzle. With this current heat wave, I finally broke 210° according to my gauge and I wasn't stalled very long in traffic.

Maybe that hood insulation that Brule used will solve another piece of my puzzle

Post by **Walt** » Mon Jul 24, 2006 8:56 am

Fab some brackets to mount the fan to the underside of the hood, and use some thin aluminum or some other thin material to make a duct to channel out from one side of the fan to the opening in the hood.

F9K9 · Post by **F9K9** » Mon Jul 24, 2006 9:03 am

Walt wrote:Fab some brackets to mount the fan to the underside of the hood, and use some thin aluminum or some other thin material to make a duct to channel out from one side of the fan to the opening in the hood.

We're on the same sheet of music, Walt

Post by **Walt** » Mon Jul 24, 2006 9:23 am

f9k9 wrote:
Walt wrote:Fab some brackets to mount the fan to the underside of the hood, and use some thin aluminum or some other thin material to make a duct to channel out from one side of the fan to the opening in the hood.
We're on the same sheet of music, Walt

Great minds think alike

F9K9 · Post by **F9K9** » Mon Jul 24, 2006 9:50 am

I found the thread. I almost hate to revive the issue but, every little bit helps qnd this is my next step. Cowl Induction Hood Mod

Post by **HenryJ** » Mon Jul 24, 2006 1:41 pm

We have endured a week of 100+ temperatures. Saturday we hit 111º, Sunday 108º, and today it is 107º so far. No records yet, but give it another week or so.

I had forgotten about the insulation I have added. That picture shows the hood and heat shield. I have also added it to the side of the AC and installed the foam insulation around the filter/dryer/dehydrator.

Good find Reed. Thanks for linking it to this thread

F9K9 · Post by **F9K9** » Tue Jul 25, 2006 2:18 am

HenryJ wrote:............... installed the foam insulation around the filter/dryer/dehydrator.

Pardon my ignorance but, could you take a pic or describe it's location?

Post by **HenryJ** » Tue Jul 25, 2006 3:11 am

Mods to the HVAC We never did do a very good job of documenting it.

The filter dryer is that aluminum canister in the big airconditioning line on the right hand side of the engine compartment.
In the past these were insulated from engine heat, as were the HVAC housings. I grabbed the foam insulating jacket off of an early ninties fullsize and installed it using the factory plastic clamp. You can just see it in the above picture. The top of it is visible at the bottom of the picture just to the left of center.

crew cab sonoma · Post by **crew cab sonoma** » Thu Jul 27, 2006 3:39 am

other things you can consider doing are removing/trimming the rubber wheelwell opening flaps.
this is probably only a good idea if you dont
off road your truck through mud and water though.
i have mine out, and it does seem to vent better.
plus, it makes getting at the spark plugs easier...

another thing you might consider, it to trim some of the hood to cowl rubber gasket back about 6-12" at each end, to open up alittle space for air to exit.

F9K9 · Post by **F9K9** » Mon Jul 31, 2006 12:11 pm

Looks like the Cowl Induction Hood Mod was almost my final piece to the cooling puzzle

I know that our temperature gauges are notoriously inaccurate but, using the same gauge to measure results should be adequate enough for our purposes. In this heat, I have been hitting 212° in traffic. I removed the stock insulation and put in a reflective type which opened up the vents in the hood and I am now running around 208° in traffic and stoplights

Post by **HenryJ** » Mon Jul 31, 2006 4:22 pm

Thanks for the write-up Reed! I added it to the Modifications Information - Cowl Hood Insulation

F9K9 · Post by **F9K9** » Mon Jul 31, 2006 5:41 pm

Thanks, Brule. I am still a little cautious with using the 3M tape in that environment but, time will tell. Hopefully, some of the steps you and I took could be left out depending on the individual CC and it's environment.

I definitely would like to see your alternator upgrade left out of my required mods to keep my temperatures lower! I will do whatever is required to depend on my CC firing up when required.

Blaze One · Post by **Blaze One** » Mon Jul 31, 2006 6:30 pm

I was just going to mention that the lack of insulation may cause paint damage , then read a link from above to find out that it doesn't matter .
So never mind then .

BTW , very clean engine bay you have there F9K9

F9K9 · Post by **F9K9** » Mon Jul 31, 2006 6:58 pm

Blaze One wrote:Wouldn't the stock insulation on the cowl induction hood help protect the paint from heat damage ?
By removing the insulation , I would be worried about the engine heat causing the paint on the top of the hood to become damaged .

Just a thought and maybe something to look out for. I dunno though.

BTW , very clean engine bay you have there F9K9

The concern about the paint has been voiced before but, Brule ran his with Zero insulation before performing what I refer to as the "bikini" insulation mod with no ill effects.

He originally performed the mod in the attempt to better seal the heat out of his K&N FIPK air intake. That is how I remember his answer to questions like yours. Steve/Killian has witnessed fires due to similar mods but, nothing has happened with our rigs that performed it (so far).

I think Steve's fires may have been related to very tightly confined engine compartments with F-bodies and his beloved Impalas. With 2" BLs, lack of gap guards in the front wheel wells and the cowl induction styled hoods, I do not believe the required ignition temperature can be attained in the CCs.

I have had a little bit of arson training and it takes a confined area for many ignition sources to build up the heat to actually become flames. Environmental concerns, locale and humidity will play a major role in ignition. I could bet you a paycheck that you couldn't produce flames where I am located at this time of yr with a kitchen match but, let a careless smoker be around Brule's neighborhood or Steve2003's location and all bets are off.

I am probably wrong but, I consider the stock insulation as primarily sound insulation.

Gawd, I went off again

Sorry.

I reread your response and all of my response was not needed.

Thanks for the clean engine bay compliment but, I'd like to see Jim's engine bay

After my distributer hassles I avoid water under my hood like the plague

WVHogRider · Post by **WVHogRider** » Mon Jul 31, 2006 8:06 pm

Even though I have enough parts laying at my house that still need to be put on the truck, I have a ????

I was planning to do the whole oil change, (oil, filter, clean the K&N/MAF, lube, change out frozen brake caliper slide pins) this weekend while I'm home. And while I was at those items, I was thinking about flushing the radiator, and putting in all new fluid, as I was a bit low last week which caused the temp. gauge to rise.

Now, since I was going to change the coolant--Should I go ahead and switch out the thermostat as well? I can only find the replacement 195°, (I learned something from another thread), and a 160° performance one from Advance Auto/Autozone, not a 180° one. There is a Mr. Gasket one at Advance, but I can't find the temp setting for it anywhere. I've only had the temp. gauge go up on two times since buying the truck new, ( 2001). Both times I was just low on coolant, with no other issues. PSST-Coolant has never been flush since buying the truck either.

Plug In Debate over Green or Orange Coolant Here.

And NO, I'm not going to replace the radiator with the bigger capacity one right now just because they are real cheap on e-bay right now or order a new thermostat on-line while I'm at the other tasks, as I'm already into enough mods. right now. If I can't get the thermostat at the store this weekend, I'll wait an order one when I have more time.

You thoughts!!!!

F9K9 · Post by **F9K9** » Mon Jul 31, 2006 8:40 pm

Well you are probably as knowledgeable or more so than I. I would dump the Dex and find anything close to what we remember that the green coolant was. All I have been able to locate is the "compatible" with any coolant. It is all a combination of coolant and distilled water for the most part. I wish I could provide helpful links on some very good threads on the topic but, am unable to right now. Drain the rad with either the stock drain on the lower passenger side radiator hose (it only turns 1/4 or 1/2 counterclockwise), buy the cheap "T" to plug into your heater hose (for the first "go-round" to hook the hose to. Find the plug under the exhaust manifold on the driver's side to remove. Run the water through as much as you can stand......use the search function to get solid help.

That block plug can be reinstalled through your fender well with patience.

As for the 180 degree stat, google "Jet Performance" and order from there. Rest assured that your need in having it will be long gone when it arrives.

WVHogRider · Post by **WVHogRider** » Mon Jul 31, 2006 9:32 pm

Is this Jet Perf. 180° stat so great, that I should just go & order one?

As I stated, I had never had a problem except for low coolant two times in 5yrs.

I found that the Mr. Gasket thermostat on Advance Auto's website is available in both 160° and 180°, but unsure if it will fit our trucks, as both Advance & Summit said they were for '85-'93 S-10 series only.

I will compare an OEM replacement 195° and the Mr. Gasket 180° sizes this weekend, unless someone beats me to it.

F9K9 · Post by **F9K9** » Mon Jul 31, 2006 11:57 pm

WVHogRider wrote:Is this Jet Perf. 180° stat so great, that I should just go & order one?
As I stated, I had never had a problem except for low coolant two times in 5yrs.

I found that the Mr. Gasket thermostat on Advance Auto's website is available in both 160° and 180°, but unsure if it will fit our trucks, as both Advance & Summit said they were for '85-'93 S-10 series only. I will compare an OEM replacement 195° and the Mr. Gasket 180° sizes this weekend, unless someone beats me to it.

The jet has nothing over any other t-stat from what I can tell. If, the Mr Gasket one is available and handy then it is a viable alternative. I'd give it a shot. I was'nt all that impressed with Jet and the haste that they placed in getting my order to me.

Post by **HenryJ** » Tue Aug 01, 2006 2:55 am

'85-'93 stats are different. You need '96-up with the bypass valve. Hypertech and Jet are the only ones available in lower temperatures that I am aware of and I have done lots of looking. Hypertech is 160 and too cold. Jet is 180.

killian96ss · Post by **killian96ss** » Tue Aug 01, 2006 6:57 am

WVHogRider, you want the 180* Jet t-stat part # 10171. Summit has them for $13.69

First you will want to thoroughly flush the cooling system with one of those tee kits like Prestone makes. Then get some regular green coolant and mix it with some distilled water (50/50 mix). I also like to use 1 bottle of Redline Water Wetter. Summit also sells this stuff for $8.95

The Water Wetter will help improve heat transfer and lower the coolant temps.

Steve

killian96ss · Post by **killian96ss** » Tue Aug 01, 2006 7:14 am

f9k9 wrote:Steve/Killian has witnessed fires due to similar mods but, nothing has happened with our rigs that performed it (so far).

I think Steve's fires may have been related to very tightly confined engine compartments with F-bodies and his beloved Impalas. With 2" BLs, lack of gap guards in the front wheel wells and the cowl induction styled hoods, I do not believe the required ignition temperature can be attained in the CCs.

I am probably wrong but, I consider the stock insulation as primarily sound insulation.

I have never witnessed fires as a result of using heat reflective insulation, but I have seen several cars with melted under hood components (plastic items) from using heat reflective insulation in the wrong areas like the hood. I still don't think it is a good idea to use heat reflective insulation on a stock style hood since it will cause under hood temps to increase and not decrease, however there shouldn't be a problem using it on a cowl style hood as long as you don't cover the entire hood.

Heat reflective insulation is best for keeping certain components cool like starters, AC components, or for protecting areas subjected to high heat like around exhaust manifolds, exhaust pipes, turbos, catalytic converters, etc.

The stock hood insulation is partly for there for paint protection on the hood, but it is mainly there for sound deadening.

Steve

Snoman002 · Post by **Snoman002** » Tue Aug 01, 2006 11:00 am

Jumping WAY back!

I looked at the louvers from Race Ace, but at $100+ for a set they just don't seem worth it. Heck for alot cheaper you could probably get a peice of sheet metal stamped with louvers, whih is all those things are.

Personally I removed the gasket at the rear of the hood when I had some heat related issues on the Bravada (funky running/shifting in heat with A/C on and towing a small trailer. Removing that gasket helped alot. The other thing I though about was getting some of the chrome fender opening surrounds that Buick is putting on alot of their cars and putting them on the truck in the same location. I would imagine it would be easy to do as all you need is a little double sided tape and a dremel, soem paint for the cuts would pobably be a good idea though.

Like this:
Buick

Or you could go all out and put some Trans Am openings on the sides of the fenders. I was looking for a pic but can't find it now.

WVHogRider · Post by **WVHogRider** » Tue Aug 01, 2006 3:23 pm

Well since I haven't really had a problem with the stock setup, I'll just put the 180° thermostat on my possible future mod list then, as I would not get it in time for this weekend, plus I have enough mods to do already. I will still flush/change the coolant though, and add the water wetter.

PS.-Looking at all the hoods you guys have, You've really tempted me to get the Ram Air hood that is on E-bay right now.

Enough mods to do for now.

Possibility of cutting open the scoops and attaching filter duct work directly to hood for true ram air.

crew cab sonoma · Post by **crew cab sonoma** » Wed Aug 02, 2006 3:49 am

Autozone has a 170 stat for our trucks. ive used it before.
the part# is 467-170. about $8 i believe.

Post by **HenryJ** » Wed Aug 02, 2006 6:24 am

crew cab sonoma wrote:Autozone has a 170 stat for our trucks. ive used it before.
the part# is 467-170. about $8 i believe.

Does it have the bypass valve?
There are tons of cheaper stats the correct diameter, but only the 195 has the bypass shut off valve. If you install a stat without this you are bypassing coolant still when the stat opens. A waste of cooling efficiency.

ace · Post by **ace** » Wed Aug 02, 2006 6:27 am

I'm really interested in these cooling mods but I'm curious by just adding the new 180 degree thermostat can I expect a cooler running truck when towing or do I need to do the addtional things like add the extra capacity radiator?

killian96ss · Post by **killian96ss** » Wed Aug 02, 2006 11:23 am

ace wrote:I'm really interested in these cooling mods but I'm curious by just adding the new 180 degree thermostat can I expect a cooler running truck when towing or do I need to do the addtional things like add the extra capacity radiator?

Every mod helps a little bit, but the real problem is the stock clutch fan.

A 180* t-stat and Water Wetter will drop the temps a little, but when it gets real hot outside like over 90* the temps will still rise until the fan locks up and stays on full time. A bigger radiator will help even more, but you will still run into the same problem on a very hot day.

It would be nice if someone just made a stock style clutch fan that engaged at a lower temperature.

The only way to keep temps low all the time is to install electric fans like HenryJ and f9k9.

Steve

F9K9 · Post by **F9K9** » Wed Aug 02, 2006 11:26 am

ace wrote:I'm really interested in these cooling mods but I'm curious by just adding the new 180 degree thermostat can I expect a cooler running truck when towing or do I need to do the addtional things like add the extra capacity radiator?

Let's put it this way. The T-stat was my first step.

Post by **HenryJ** » Wed Aug 02, 2006 1:26 pm

Agreed. You need more than one piece to see the picture in the whole puzzle. While one piece may offer a hint to the full picture, you will not see it clearly until you have more pieces.
Once it all comes together, you can really appreciate how all the pieces make a really good picture

F9K9 · Post by **F9K9** » Wed Aug 02, 2006 2:36 pm

f9k9 wrote:Looks like the Cowl Induction Hood Mod was almost my final piece to the cooling puzzle

I spoke up a little to soon

Yesterday, I left it parked running for approx. 10 minutes and jumped into heavy traffic afterwards. I was over "my" gauge's 210° mark and 10 minutes of stop and go traffic did not bring it below 210°. . I did not look at my alternator gauge. Today I was in traffic, did not go over 210° but, I did look at my alternator output. It was down to 12 volts

Looks like a CS-144 alternator is next for me and will be pulling that rear seal in the summer months to see what that buys me.

killian96ss · Post by **killian96ss** » Wed Aug 02, 2006 2:54 pm

f9k9 wrote:will be pulling that rear seal in the summer months to see what that buys me.

If the CC's pull fresh air in for the AC system through the cowl vents you might experience a drop in AC performance. I have removed the rear cowl seal on my SS before to help vent the engine compartment a little better and found that my AC did not work nearly as well as it did with the seal in place. Maybe the CC's don't work this way, but a lot of vehicles do pull fresh air in through the cowl vents and the rear cowl hood seal is there to prevent hot air from being drawn in through these vents. You could always try it and see if there is any difference in AC performance.

Steve

F9K9 · Post by **F9K9** » Wed Aug 02, 2006 2:57 pm

killian96ss wrote:
f9k9 wrote:will be pulling that rear seal in the summer months to see what that buys me.
If the CC's pull fresh air in for the AC system through the cowl vents you might experience a drop in AC performance. I have removed the rear cowl seal on my SS before to help vent the engine compartment a little better and found that my AC did not work nearly as well as it did with the seal in place. Maybe the CC's don't work this way, but a lot of vehicles do pull fresh air in through the cowl vents and the rear cowl hood seal is there to prevent hot air from being drawn in through these vents. You could always try it and see if there is any difference in AC performance.

Steve

Ahhhh, another piece of the puzzle I was unaware of. Thanks, Steve!

Post by **HenryJ** » Wed Aug 02, 2006 3:06 pm

Run the AC in Max and it recirculates.

killian96ss · Post by **killian96ss** » Wed Aug 02, 2006 3:16 pm

HenryJ wrote:Run the AC in Max and it recirculates.

Good to know!

In normal mode does the AC system pull air in through the cowl vents?

Steve

WVHogRider · Post by **WVHogRider** » Wed Aug 02, 2006 3:36 pm

I did not find a 170* for our trucks on any site. A couple people on another S Series site said that the 160* stat will tend to cook the oil over an extended period of time of normal driving, and that it should be used more for the race/performance set up. True?

Post by **HenryJ** » Wed Aug 02, 2006 3:38 pm

killian96ss wrote:...In normal mode does the AC system pull air in through the cowl vents?

Yes. You can drop the glove box and watch the door for the HAVC fresh air intake open and close. With a cowl hood using the vent position is not very useful as the engine heat is drawn in.

The E-fans do compensate for any losses from the intake of warmed air though. They improve the airflow enough that the condensers transfer of heat more than makes up for a warmer air charge.

WVHogRider wrote:...A couple people on another S Series site said that the 160* stat will tend to cook the oil over an extended period of time of normal driving, and that it should be used more for the race/performance set up. True?

Cook the oil? No. Used for racing, true. Good idea for street use? No. - 180 degree thermostat???

The graph below illustrates the importance of how critical optimum coolant temperature is to the longevity and performance of an internal combustion engine. Cool water makes good horsepower, to a point. Warm water minimizes engine cylinder wear, to a point also.

However, there is a "middle ground" where both optimum performance as well as minimal wear share similar characteristics. That "magic" number lies in the 175-180 degree range, which requires a 180 degree thermostat..

The all too commonly used 160 degree thermostat is way too low to be considered for performance or engine longevity. As the chart illustrates, engine wear increased by double at 160, than at 185 degrees. So then, why do the 160's exist in the first place? The 160's were commonly used in older, open loop cooling systems where only 6 pound radiator caps were used, and low 212 degree boiling points were experienced. In contrast, modern cooling systems can see upwards of 260 degrees in coolant temperature with radiator pressures exceeding 45 pounds. Many early hot rodders found the 160's to be better performing than the 190's, however, the in between "180" appears to satisfy both ends of the spectrum. The correct water temperature is required for the cylinders to achieve a minimum specific temperature in order to allow a fully homogenized Air/Fuel mixture to combust efficiently. Guess what the minimum number is… right! 180 degrees. Even so, you might see some still recommending the lower 160's, for no other reason than to possibly get that last drop of horsepower out, at the high price of dramatically reducing the life of the engine and it's internal components.

WVHogRider · Post by **WVHogRider** » Wed Aug 02, 2006 3:51 pm

Note to self--Get parts from Autozone first thing in morning, Kick store manager in groin for having 160's and 195's but no 180's before leaving, put ordering of 180* stat on future mod. list....

F9K9 · Post by **F9K9** » Wed Aug 02, 2006 4:41 pm

HenryJ wrote:'85-'93 stats are different. You need '96-up with the bypass valve. Hypertech and Jet are the only ones available in lower temperatures that I am aware of and I have done lots of looking. Hypertech is 160 and too cold. Jet is 180.

Jet is the ONLY 180° T-stat with a bypass that we are aware of. May as well order it ASAP. I think I ordered mine online but, if calling is an option then, I would do that. Sometimes the sales reps can speed things up.

It worked with Summit for me.

Snoman002 · Post by **Snoman002** » Wed Aug 02, 2006 4:42 pm

WVHogRider wrote:Note to self--Get parts from Autozone first thing in morning, Kick store manager in groin for having 160's and 195's but no 180's before leaving, put ordering of 180* stat on future mod. list....

HJ, that is a great graph. Mind if I borrow that for another forum?

Post by **HenryJ** » Wed Aug 02, 2006 4:51 pm

Snoman002 wrote:...that is a great graph. Mind if I borrw that for anothr forum?

Give the credit to http://performanceunlimited.com/ , that is where I found the information.
Go forth and spread the information!

Snoman002 · Post by **Snoman002** » Wed Aug 02, 2006 5:05 pm

Thanks HJ, will do.

And DANG, I need to work on my spelling.

Snoman002 wrote:Mind if I borrw that for anothr forum?

Post by **HenryJ** » Wed Aug 02, 2006 5:09 pm

Snoman002 wrote:...I need to work on my spelling.

Wrong. Slpeing ins't ipmorantt!

04crewvt · Post by **04crewvt** » Wed Aug 02, 2006 5:19 pm

A little know oddity, as long as the first and last letters of a word are correct and all the consonants are there we will almost always be able to figure out the correct word without even trying to, we just will fill in the missing/scrambled letters automatically. Doubled letters like in {spelling} can be missing one and we still will recognise the words.

On a cooling note I have had a couple of hot days here this week and so far my temp has stayed right at 200-210 on the guage right where it is normally so for me it looks like I am ok with no cooling mods right now I just will keep an eye on things.

Post by **HenryJ** » Wed Aug 02, 2006 5:23 pm

04crewvt wrote:...I have had a couple of hot days here ...

What is that in Vermont , upper 70's

04crewvt · Post by **04crewvt** » Wed Aug 02, 2006 5:28 pm

Actually hit 95 with 70 % humidity yesterday and 91 today. In the 12 years I have been here it has broken 100 less than a dozen times.

F9K9 · Post by **F9K9** » Wed Aug 02, 2006 5:32 pm

killian96ss wrote:
HenryJ wrote:Run the AC in Max and it recirculates.

Good to know! In normal mode does the AC system pull air in through the cowl vents?

Steve

Yes, I was going to comment on Brule's info but, I would have cut my own throat.

Being a minority nowadays (smoker) I remember riding with my sister and her husband when I was young. They were both smokers and the recirculated air was very uncomfortable to me. I still refrain from using the option because of that.

In cooler weather I have always got a kick out of people driving around with steamed up windows in older japanese made vehicles. They spend a lot of time wiping off the inside of the windows when all they have to do is take the HVAC option off of recirculate

04crewvt · Post by **04crewvt** » Wed Aug 02, 2006 5:33 pm

Just remeber a heat advisory in Vermont is like a snow day in Arizona. Both are so infrequent that they wreak havoc because no one is prepared for them.

WVHogRider · Post by **WVHogRider** » Wed Aug 02, 2006 5:37 pm

If I weren't already divorced, she would have definitely left after I found this site and finding/spending mod $$$$$.

So, If I order this Jet 180 tonight, do I need to get a gasket while I'm at the store tomorrow?

Summit says that it does not come with a gasket and I forgot to check on Jet's site, nor did they have a shipping estimate page. However, looking at the picture, it looks like there is already a gasket attached to the rim of the thermostat.

It would be here by Saturday from Summit.

Post by **HenryJ** » Wed Aug 02, 2006 5:40 pm

It may not come with the seal. You can reuse the one off your stat , or pick one up at the parts store for a few dollars.
Welcome to the addiction

F9K9 · Post by **F9K9** » Wed Aug 02, 2006 5:45 pm

WVHogRider wrote:If I weren't already divorced, she would have definitely left after I found this site and finding/spending mod $$$$$.

So, If I order this Jet 180 tonight, do I need to get a gasket while I'm at the store tomorrow? Summit says that it does not come with a gasket and I forgot to check on Jet's site, nor did they have a shipping estimate page. However, looking at the picture, it looks like there is already a gasket attached to the rim of the thermostat. It would be here by Saturday from Summit.

It does not come with a gasket. You should be able to use your old one. They are just rubber rings around the outside edge of a T-stat. No cork/paper ones of yesteryear

Worst case scenario is if, breaks somehow and parts stores don't have them seperate is just buy a cheapy T-stat and use it.

F9K9 · Post by **F9K9** » Wed Aug 02, 2006 5:48 pm

HenryJ wrote: Welcome to the addiction

2X

Dayem, I never thought to warn you about Summit

Post by **HenryJ** » Wed Aug 02, 2006 6:01 pm

Keep track of which side of the seal has the raised rib on it. That does seem to make a difference. Watch for leaks after you're done. Overtorquing will not fix a leak. You need a new seal if it does leak.

F9K9 · Post by **F9K9** » Wed Aug 02, 2006 6:11 pm

HenryJ wrote:Keep track of which side of the seal has the raised rib on it. That does seem to make a difference. Watch for leaks after you're done. Overtorquing will not fix a leak. You need a new seal if it does leak.

Did you forget you were talking to a HD Fan? Who would know more about leaks than one of his sort?
-
J/K of course

killian96ss · Post by **killian96ss** » Wed Aug 02, 2006 6:17 pm

HenryJ wrote:Overtorquing will not fix a leak.

True, and it's also a good way to strip the threads in the aluminum intake.

If you have a torque wrench the 2 bolts should be tightened to 14 foot pounds.

If you don't have a torque wrench just use a small ratchet or wrench so you don't get all crazy torquing it down.

Steve

WVHogRider · Post by **WVHogRider** » Wed Aug 02, 2006 6:18 pm

"The ideal thermostat for our truck is 180*.", he says. "It's a good mod for if you do a lot of towing or off-roading", he says.

Thermostat ordered.

Hopefully, it will be here Saturday morning, as I'm only about 1.5 to 2 hours away from the Ohio distribution center.

Might as well try to get that in while I'm working on it. Busy weekend then--Decide on tires and get them mounted on the new rims, do the whole oil change, filter cleaning, lube, replacement on cross-threaded wheel stud, replacement of frozen brake pins, flush/refill radiator, mount step bars, trans. cooler, etc.

I was even going to try to fit in getting the new exhaust or tinted front windows this weekend, but looks like those are out of the question.

F9K9 · Post by **F9K9** » Wed Aug 02, 2006 6:24 pm

You do have a busy weekend planned

No need to worry about it now but, don't be surprised if you throw a SES light this fall with that T-stat. It's no biggee, easily corrected and we'll cross that bridge if, you come to it.

WVHogRider · Post by **WVHogRider** » Wed Aug 02, 2006 6:41 pm

f9k9 wrote:

Did you forget you were talking to a HD Fan? Who would know more about leaks than one of his sort?

But the only sad part is that I've only had oil leaks after the stealership had worked on it, but never when I did anything to the engine.

HenryJ wrote:
Overtorquing will not fix a leak.

True, and it's also a good way to strip the threads in the aluminum intake. If you have a torque wrench the 2 bolts should be tightened to 14 foot pounds. If you don't have a torque wrench just use a small ratchet or wrench so you don't get all crazy torquing it down.

Steve

Yep, I got a torque wrench for Christmas one year after I had tightened my lug nuts the old Monte Carlo I use to have.

My dad just told me to tighten them, but never explained the overtightening side of "Tight". Let me just say that my dad learned to says "You don't need to put your Gorilla Pounds of torque on'em, but just tighten them. 4 out of the 5 lugs snapped off one of the wheels when I backed it out of the garage.

F9K9 · Post by **F9K9** » Wed Aug 02, 2006 7:11 pm

WVHogRider wrote:
But the only sad part is that I've only had oil leaks after the stealership had worked on it, but never when I did anything to the engine.

I was referring to the long past dark days that have long past

F9K9 · Post by **F9K9** » Wed Aug 02, 2006 7:32 pm

f9k9 wrote:Looks like a CS-144 alternator is next for me and will be pulling that rear seal in the summer months to see what that buys me.

CS144 high output alternator

I've just ordered a new Delco 170 amp CS-144 (from a source to remain known only to me until fully tested and after consultation with HenryJ) If, you read that long thread provided, you will see I made several attempts to have one built locally and I just gave up with my local shop or my inability to get my friggin' point across to them.

The unit I ordered is 100% new and no core charge was required. It probably has the incorrect bearings according to Brule's requirements but, I have only had to replace my stock units once in the last 7 or 8 rigs. I just want to get this thing running cool and move onto to simpler mods

Post by **HenryJ** » Thu Aug 03, 2006 3:11 am

f9k9 wrote:... It probably has the incorrect bearings according to Brule's requirements but, I have only had to replace my stock units once in the last 7 or 8 rigs.

Your last seven or eight probably didn't run a CS144 with needle bearings

When your rear bearing fails you can buy a good rear cover and have the sealed bearing installed, as long as it doesn't ruin the armature shaft. Nothing to lose sleep over.

crew cab sonoma · Post by **crew cab sonoma** » Thu Aug 03, 2006 8:17 am

HenryJ wrote:
crew cab sonoma wrote:Autozone has a 170 stat for our trucks. ive used it before.
the part# is 467-170. about $8 i believe.
Does it have the bypass valve?
There are tons of cheaper stats the correct diameter, but only the 195 has the bypass shut off valve. If you install a stat without this you are bypassing coolant still when the stat opens. A waste of cooling efficiency.

yes, that one does indeed have the bypass valve on it.

but ill have to disgree with you about the loss of effiency part.
i removed the bypass valve from my 170 more than a year ago,
and even in 100 deg. weather, i had no problems keeping under 180.

in fact, short of serious overheating, the extra bypass flow should
help increase circulation within the engine, and help promote more homogenous temps between the block and heads.

it may even help reduce the formation of steam pockets in the cyl. heads.

Post by **HenryJ** » Thu Aug 03, 2006 1:30 pm

crew cab sonoma wrote:...Autozone has a 170 stat for our trucks. ive used it before.
the part# is 467-170. about $8 i believe...does indeed have the bypass valve on it.

What is the brand? Do they also offer the 467-180 ? I have done a pretty exhausting search and found nothing. Lots of talk but no one can show me a picture nor can I find a place that offers them.

Autozone online wrote:Search Term: 467-170
Sorry, there are no parts that match your search term.

Looks like you're going to have to prove it

... ill have to disgree with you about the loss of effiency part.
i removed the bypass valve from my 170 more than a year ago,
and even in 100 deg. weather, i had no problems keeping under 180.

in fact, short of serious overheating, the extra bypass flow should
help increase circulation within the engine, and help promote more homogenous temps between the block and heads.

it may even help reduce the formation of steam pockets in the cyl. heads.

Bypass is what it does. It bypasses the radiator. That fluid does not enter the radiator to transfer heat. That in itself says a reduction in heat transferred.
Recirculating the coolant is fine. That does even the temperatures within the engine and does help prevent cavatation in the water pump. The valve is open to some degree and recirculating with the thermostat in all positions except for wide open where maximum cooling is needed.

Why would you want to run without it, or remove it? I see no advantage. Well, perhaps getting a cheaper thermostat is an advantage?