Cooling System - mods run cooler

Post by **HenryJ** » Thu Aug 03, 2006 2:07 pm

Another idea no one here has tried- JTR Ford Explorer clutch fan

JTR wrote: If you want to improve fuel-mileage and performance, a fan clutch assembly from a 1993-1997 Ford Explorer with the 4.0 V6 can be installed into the 1996-2004 S-10 trucks with the 4.3 V6. The Ford fan assembly is more efficient, and much quieter, but slightly less powerful than the S-10 fan assembly. This fan assembly is 18" in diameter (compared to 19" for the stock S-10 fan). The Ford unit weighs about 1-1/4 lbs less than the 4.3 V6 fan assembly.
S-10 4.3 V6 heavy-duty replacement radiator, 1996Ð2004
1996-2004 S10 Fan Ford Explorer Fan

The Ford fan clutch is 1 inch shorter than the S-10 fan clutch, and it positions the fan about 1/2" closer to the engine, which improves efficiency in the S-10 Truck by placing the fan blade behind the "ring" section of the shroud. The stock S-10 fan blade protrudes forward of the "ring" and some of the air is thrown off the front of the blade and back into the sides of the shroud -- decreasing efficiency.
S-10 4.3 V6 heavy-duty replacement radiator, 1996Ð2004

FORD EXPLORER FAN INSTALLED
IN 1996–2004 V6 S10

FORD EXPLORER FAN INSTALLED IN 1996-2004 V6 S-10

This is the Ford Explorer fan installed into the S-10. It may appear slightly "undersize" in the shroud, but it does a very good job of cooling the S-10. When used with the Heavy-Duty replacement radiator, the engine will not run hot, even when the outside temperature is over 105°F.

F9K9 · Post by **F9K9** » Thu Aug 03, 2006 3:08 pm

HenryJ wrote:Another idea no one here has tried- JTR Ford Explorer clutch fan

That might be worth trying before going to LS-1 E-fans but, I don't know how much stock I would put in that guy after reading a borrowed copy of his overpriced V-8 swap book. I came across that mod a few months back and at the time he sold the extra capacity radiators at a pretty good price.

Seems to me he has one goal! MONEY!

Post by **HenryJ** » Thu Aug 03, 2006 3:12 pm

It would be nice to know if it operates, or locks at a lower temperature. That might be another option for matching the lowered temp stat?

F9K9 · Post by **F9K9** » Thu Aug 03, 2006 3:33 pm

HenryJ wrote:It would be nice to know if it operates, or locks at a lower temperature. That might be another option for matching the lowered temp stat?

I should have reworded my comment. I think this is something that someone should look into before diving into the LS-1 e-fans. If one can be found locally at a salvage yard for a decent price then try it. I might have tried it if I wasn't already commited to the LS-1 e-fan/CS-144 conversion

Btw if, I get the yellow CAB cooled down then this is absolutely the last "major" mod I am doing until 75K

Snoman002 · Post by **Snoman002** » Thu Aug 03, 2006 4:23 pm

Or just spend $30 bucks and get a taurus e-fan. Add a couple more bucks for a temp switch to turn them on and BAM, good cooling.

F9K9 · Post by **F9K9** » Thu Aug 03, 2006 4:45 pm

Snoman002 wrote:Or just spend $30 bucks and get a taurus e-fan. Add a couple more bucks for a temp switch to turn them on and BAM, good cooling.

I understand that the Taurus e-fans work for a lot of people. The LS-1 fans pull less amps at 100% and with the Flex-a-lite Variable seped Controller the LS-1 e-fans pull something like 60% at start up (and that is delayed for 5 seconds (approx). I am already seeing my alternator output at about 12 volts in traffic and idling in hot weather. It's just my preference to stick with the combination that I am running now. I'd love to see the results of a CC member running a Taurus E-fan. I think our 4WD's affect the equation.

Snoman002 · Post by **Snoman002** » Thu Aug 03, 2006 5:24 pm

Hey, don't get me wrong, the LS-1 fans are great (and if you have it and it works why change it). BUT, the Taurus fan pulls plenty of CFM (enough to cool a mild V-8 with a stock HD rad.) and are at least two stage so your not always pulling the high amps.

Hmmm, wonder how the taurus fan would work with just an on-off controller for the low speed and the adjustable controller for the high speed?

2kwik4u · Post by **2kwik4u** » Fri Aug 04, 2006 4:10 am

f9k9 wrote:
Snoman002 wrote:Or just spend $30 bucks and get a taurus e-fan. Add a couple more bucks for a temp switch to turn them on and BAM, good cooling.

I understand that the Taurus e-fans work for a lot of people. The LS-1 fans pull less amps at 100% and with the Flex-a-lite Variable seped Controller the LS-1 e-fans pull something like 60% at start up (and that is delayed for 5 seconds (approx). I am already seeing my alternator output at about 12 volts in traffic and idling in hot weather. It's just my preference to stick with the combination that I am running now. I'd love to see the results of a CC member running a Taurus E-fan. I think our 4WD's affect the equation.

I'll be running one here soon.

I dropped the truck off at the dealer again this morning to get the radio, and console replaced, and commented again that coming through Nashville the other day the outside temp was 101, and the trucks temps was on the north side of 210. He flat out told me, he can't issue any work, until it consistantly gets over 235. Cooling mods are in my near future. $5 low temp thermostat, and a nice efan are the first on the list. Moving the tranny cooler out of the radiator is also on the list.

Local junkyard has 10-12 Taurus Efans still installed in cars, and I intend to go get one here soon, and wire it in to the crew. I wanted to try the LS1 dual fans, however at $15, I can't see passing up the Taurus fan. Especially after installing this in about 4-5 other local trucks with great results. While it's not just as easy as "throwing it on there", and putting a temp switch on it, and BAM.....it's easily under $100 mod.

Also a comment about the lower thermostats, and the idea that it's not going to stay at that temperature if you change JUST that. While I do agree that you need to have a fan "turn on" earlier to take full advantage, one must also realize that the stock clucth fan provides LESS airflow than moving ~35mph. So while the truck might not stay that cool in stopped traffic at idle, at any noticable speed there is still enough airflow to keep the truck that cool. It's not as though there is zero airflow until the clutch fan engages. SO, saying that you will see no cooling benefit from the lower stat without also modding the fan is a bit of misinformation.

Post by **HenryJ** » Fri Aug 04, 2006 5:55 am

2kwik4u wrote:...$5 low temp thermostat...

Be sure to let us know if you find that "unicorn". I still do not believe that one with a bypass valve exists.
I wish you luck with the Taurus fan. there have been lots of complaints about the amperage draw of those units, so add the price of the heavy duty relays and a bigger alternator to your list. Not to say that the LS1 fans don't require the same.
Another thing to consider is that if one of the motors fails on a dual fan , you still have one to get you in.

There is no doubt that a 180 stat alone will lower the operating temperature as long as there is sufficient heat to air transfer. Changing the fan was the last change that I made. The Idea here is to have the whole package working together. That is why the fan engagement needs to match.

Different conditions will work better for different people. If you never crawl the desert on 100+ temperatures you may not need all the mods. In a temperate climate less airflow or coolant capacity may work just fine. Driving habits may need to be considered as well.

If it works for you, great.

border man · Post by **border man** » Sat Aug 05, 2006 7:29 pm

I/m running the taurus fan......

, on my Taurus sedan that is..

crew cab sonoma · Post by **crew cab sonoma** » Thu Aug 10, 2006 9:18 am

HenryJ wrote: 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.

Looks like you're going to have to prove it

sorry. it must be an obsolete part #.... just searched for it myself, couldnt find it anymore. but i have bought at least two of them in the past.
i THINK the brand was Motorad, but it doesnt look like Autozone carries that brand any more.
i used to have to look it up for a 96 model, as that part# didnt show up for the 2001...

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?

well, why NOT remove it, if it doesnt cause a problem to do so???
like i said, ive been running my truck without it for more than a year now, with no problems from it. i cant promise it wont cause problems for anybody else, but it is working fine for me....
why pay more for a thermostat if you dont have to???

i could see where it might cause problems in seriously marginal cooling conditions, but my truck seems to be passing more than enough coolant to the radiator for cooling.

WVHogRider · Post by **WVHogRider** » Fri Aug 11, 2006 9:38 am

f9k9 wrote:
HenryJ wrote: Welcome to the addiction
2X

Dayem, I never thought to warn you about Summit

f9k9--The thermostat was on my doorstep the very next day, with the free hat and decals. As I said in another post, I'll try to get this done this week.

F9K9 · Post by **F9K9** » Fri Aug 11, 2006 10:42 am

I recall now that I ordered from Jet Performance and not Summit. Am glad they got an order out promptly for ya'

F9K9 · Post by **F9K9** » Sun Jan 21, 2007 11:22 am

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

That's what I plan to run.

I am now considering this mod, as well

ZR2 USA has a write up and pics of a member's INSTALL . The louvers can be found HERE! I started looking for louvers because of all the threads on them on the XJ forums and their overheating issues.

LonestarZ · Post by **LonestarZ** » Sun Jan 21, 2007 2:52 pm

I thought you had a cowl induction hood already? I can't see these offering much of an additional benefit if you have the cowl.. My 2 cents.

F9K9 · Post by **F9K9** » Sun Jan 21, 2007 3:04 pm

LonestarZ wrote:I thought you had a cowl induction hood already? I can't see these offering much of an additional benefit if you have the cowl.. My 2 cents.

That was my thought on the topic but, at this point, I am not ruling out any mod that may assist in cooler operating temperatures.

2kwik4u · Post by **2kwik4u** » Fri Jun 22, 2007 10:47 am

2kwik4u wrote: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.

Look at me....researching larger capacity radiators almost exactly one year later!!!!

Thanks again guys for the super informative post on this.

F9K9 · Post by **F9K9** » Fri Jun 22, 2007 1:37 pm

2kwik4u wrote:................Look at me....researching larger capacity radiators almost exactly one year later!!!!................

We're proud of ya' Mike

F9K9 · Post by **F9K9** » Sun Aug 19, 2007 10:38 am

I am back to square one on the cooling issue with over $1,000 invested in it (that may be a tad on the conservative side)

1. Extra capacity radiator..........$160
2. LS1 electric fans with VSC.....$200
3. 180° Jet Performance t-stat..$20
4. 170 AMP alternator...............$200+
5. Cowl induction hood ............$475 (was planned as a visual mod but, also became a cooling one to allow the hot air to escape (The cost includes painting but, not 6 hrs of driving time, my time and fuel).

I just got back from Hot Springs, AR for a S-10 meet at the SuperLift off road Park. It is approx 600 miles one way, The temps have been at or over 100° each day, my rig has been cooling well up until now. I experienced temps rising towards 235° while at speeds over 60 MPH traveling to and from the meet.

I am topped off with a fresh dose of 50/50 green coolant and distilled water. I am running it with Redline Water Wetter! Radiator is full and the efans are both running full time with my override on switch.

I can turn off the AC and suffer but, the engine temperature will drop below 210° within a few minutes (seems like hrs to me) and I have to keep an eye on the gauge.

I changed the oil before the trip and used 10-30W SUV Mobile 1 synthetic oil instead of the regular 5-30W Mobile 1 oil.

Any thoughts on the issue? I would try a new t-stat, and maybe looking at crap built up from by off road adventures between the radiator and AC thingy but, I keep my stuff pretty clean.

Suggestions?

killian96ss · Post by **killian96ss** » Sun Aug 19, 2007 11:09 am

Maybe you have reached the upper limit of the LS1 fans or need a better seal between the e-fans and the radiator?

Maybe the Jet t-stat is stuck in the closed position?

I was driving in 110* temps a week ago (mostly stop and go) and my temps never went above 220* with the stock cooling system (Jet 180* t-stat, green coolant, and Water Wetter are the only upgrades).

Steve

F9K9 · Post by **F9K9** » Sun Aug 19, 2007 11:19 am

killian96ss wrote:Maybe you have reached the upper limit of the LS1 fans or need a better seal between the e-fans and the radiator?........Steve

I think you are on to something there, Steve! I do remember some trimming on the LS1 fans that Brule did. I found that info after my install but, it was readily available to me at the time. I just missed it and it seemed trivial at the time.

Can I rule out the oil and AC compressor?

killian96ss · Post by **killian96ss** » Sun Aug 19, 2007 11:34 am

f9k9 wrote:Can I rule out the oil and AC compressor?

I think so, since they have nothing to do with cooling.

It is normal for the temps to climb while the AC is on.

Steve

F9K9 · Post by **F9K9** » Sun Aug 19, 2007 11:54 am

killian96ss wrote:.......I think so, since they have nothing to do with cooling. ...........It is normal for the temps to climb while the AC is on. ......

Was covering all bases but, didn't know if an ac compressor could begin to fail and start to "drag" or cause an increased amount of hp to move it when, it was about to fail. It is weird that at a certain point in the day when outside temps fell to below a certain point (under 100°) that the system was faultless. again.

killian96ss · Post by **killian96ss** » Sun Aug 19, 2007 12:19 pm

f9k9 wrote:It is weird that at a certain point in the day when outside temps fell to below a certain point (under 100°) that the system was faultless. again.

This is kind of what made me think you were at the limit for the LS1 fans, but since Brule is running the same set up without problems (plenty of 100 + degree days where he is) it makes me think something else is wrong like the seal between the fans and radiator, a sticking t-stat, or maybe something is wrong with the fan speeds (not pulling enough air).

Steve

F9K9 · Post by **F9K9** » Sun Aug 19, 2007 1:22 pm

2 years on the stat is enough cause to replace it. I am going to replace it and review the LS1 efan mod to clean up what trimming that I missed. It will be easy enough to double check for any debris between the radiator and AC "thingy" at that time.

Thanks for the brain storming session, Steve

killian96ss · Post by **killian96ss** » Sun Aug 19, 2007 3:49 pm

There is also a small possibility that something is wrong with your water pump.

As you know with any GM product a low mileage (factory) or even new part does not mean it will last a long time.

I've had pretty good luck so far with my ZR2 (nothing replaced so far @ 35k)

, but when I had the Crew I had all sorts of things fail withing the first 30k miles like a PS pump, 1 steering gear box, 2 A/C compressors, intake manifold gasket, 2 batteries, oil pan gasket, exhaust gaskets, etc.

From 30k to 90k the Crew did pretty good

except for the failing injectors.

I had very similar luck with my SS during the first 30k miles (water pump, alternator, intake gasket, PS pump, etc.), but after that no more problems.

GM parts seem to fail most during the first 30k miles, so keep an eye on that pump if the other fixes don't work.

Steve

F9K9 · Post by **F9K9** » Sun Aug 19, 2007 5:32 pm

I was thinking about replacing the water pump if, replacing the tstat and sealing the LS1 efans didn't help. I will not order directly from Jet Performance again (took to long) and see what deals Summit has on tap. These temps are bound to break shortly

Post by **HenryJ** » Tue Aug 21, 2007 2:40 pm

Clean the condensor , radiator, trans cooler and between the radiator and condensor.

At highway speeds the normal airflow , even without the fans turning , is more than they could move. That takes the fans out of the equation.

It is amazing just how fast debris can build up. Bugs and vegetation plug things up fast. That is the first place I would look.

If that doesn't do the job we may have to look at improving the airflow available. Perhaps relocating that trans cooler?

F9K9 · Post by **F9K9** » Tue Aug 21, 2007 3:44 pm

HenryJ wrote:.............If that doesn't do the job we may have to look at improving the airflow available. Perhaps relocating that trans cooler?

All good ideas that I will follow up on, Brule! I have not even ordered the Jet t-stat yet. I need to get my other ride back together, in case, I need to do parts running.

BTW Welcome back!

F9K9 · Post by **F9K9** » Tue Aug 28, 2007 2:41 pm

HenryJ wrote:Clean the condensor , radiator, trans cooler and between the radiator and condensor..........If that doesn't do the job we may have to look at improving the airflow available. Perhaps relocating that trans cooler?

OK, I replaced the Jet Performance 180° t-stat with another one last night. I let it run idling with the A/C on last night and it never broke 205° Outside air was approx 80°. Going to work today it stayed at around 200° with the outside air at 85°. During lunch (outside air temp at approx 95°) with stop and go traffic and a line at the drive thru I approached 220°. It's better but, it only hit 95° here today so, the problem is still not solved. I visually inspected the front of the tranny cooler and condenser. They look free of debris but, I know stuff could be between the fins. I also separated the rad and the condenser and it is visually clean.

I would assume that a high pressure spray at a car wash would be best to use in this situation but, so many things have changed since I wrenched in yesteryear that the high pressure may be bad and bend the aluminum that is in use today.

If, my approach is safe then I plan on pulling the grille, headlights and the KCs off of my brush guard to fully access the area. The brush guard can be uninstalled by one man. But, reinstalling solo is a PITA. I can remove the front bolts on the brush guard bracket and loosen the rears to tilt it forward and down to remove the headlights and grille assembly.

Any thoughts?

KedExx · Post by **KedExx** » Tue Aug 28, 2007 5:17 pm

Didnt you say that when you changed your oil, you found some metal on the drain plug? "If" you have some additional friction inside the engine ( not sure whats going on in there) that "may" be adding to your overheating. We had something simular going on with our 565ci in our race car. Its a long shot, but it may be something to think about

Another thing to think about. Have you tried a aftermarket temp guage? Maybe your sending until/guage is on the fritz

F9K9 · Post by **F9K9** » Tue Aug 28, 2007 6:06 pm

KedExx wrote:Didnt you say that when you changed your oil, you found some metal on the drain plug? "........

A good point and something I am looking forward to checking when I am am due an oil change at 3K. Hot Springs is around 600 miles one way, I put maybe, 100 miles on it while there and 50 miles on it since my return. I really don't think I paid attention to the oil drain plug before this last change so, it may just be normal debris on the magnet after 30K. Cooling has been good up until that trip and the only change that I made was in the oil going from Mobil1 5-30w to 10-30w. I am basically waiting on a definitive answer on cleaning the radiator and condenser before before I give it much more thought.

BADs Crew · Post by **BADs Crew** » Wed Aug 29, 2007 1:18 am

I use to do home AC installations and repair. When I would performing PM inspections I always cleaned both the A coil and condensing coil. There are different Coil Cleaners on the market that work very well with little effort.
If you go this route look for a non acidic type but you want something that cuts grease. The acidic type does a good job but will take off the paint. If you can't find it at the auto parts store try Home Depot or any Refrigeration supply store. I wouldn't use high pressure because you can bend the thin fins and they are a PITA to fix.

killian96ss · Post by **killian96ss** » Fri Oct 12, 2007 1:34 pm

I had a thought today about how the stock clutch fan combined with a cowl induction hood might make an overheating situation worse.

The stock thermal clutch fan senses engine compartment heat and locks up when it reaches a preset point.

If you add a cowl induction hood and drop underhood temps 5-15 degrees then your clutch fan will engage later a higher engine temp than it would normally engage.

Even though the air temp around the engine is a little cooler with a cowl hood the overall engine temp should be the same as with a stock hood except for really hot days.

It seems to me that if you get a cowl hood it would also be a good idea to run e-fans.

Does any of this make sense or am I just trying to confuse myself?

Steve

Post by **HenryJ** » Fri Oct 12, 2007 1:43 pm

killian96ss wrote:The stock thermal clutch fan senses engine compartment heat and locks up when it reaches a preset point...Does any of this make sense or am I just trying to confuse myself?

Maybe a little confused.
The heat sensitive "spring" is on the front center of the fan clutch. It is always turning and drawing some air through the radiator. The heat comes from the radiator.
I don't see any way the heat would come forward from the engine to affect the engagement point for the clutch fan.
I kind of see where you are going here, and maybe in a drastic situation the engine compartment heat might influence the clutch fan, but that would probably indicate and engine compartment fire.
I am going to say that the increased engine compartment ventilation is not going to affect the fan clutch operation.

killian96ss · Post by **killian96ss** » Fri Oct 12, 2007 2:03 pm

HenryJ wrote:I am going to say that the increased engine compartment ventilation is not going to affect the fan clutch operation.

After your explanation I think I agree with you more than me.

Steve

Post by **HenryJ** » Fri Oct 12, 2007 2:16 pm

killian96ss wrote:...I think I agree with you more than me.

Seek medical attention! Someone call 911!

You must be very sick! Can't someone please HELP HIM!
Oh, the tragedy...

crew cab sonoma · Post by **crew cab sonoma** » Wed Oct 17, 2007 3:09 pm

another possibility... at higher speeds, air may be flowing INTO the back of the cowl hood opening, from the high pressure area that forms at the base of the windshield, and maybe reducing flow through the radiator....
BTW, the non-bypass thermostat worked great this summer, even through 2+ weeks of 100+ deg. weather here...temps rarely got above 165 deg. (without A/C)....

F9K9 · Post by **F9K9** » Wed Oct 17, 2007 4:36 pm

crew cab sonoma wrote:..............BTW, the non-bypass thermostat worked great this summer, even through 2+ weeks of 100+ deg. weather here...temps rarely got above 165 deg. (without A/C)....

You had to bring this up again.

I figured I'd wait to next summer to revisit this issue. I still don't think a non bypass stat is cool for me. We don't have idiot lights that I have seen. If. that sucker is stuck closed for too long and you are like me, it will be too late when you notice the temps, steam and knocking. I'll spend a few bucks more on insurance any day unless I was trying to cook a motor as an excuse for a 5.7L.

crew cab sonoma · Post by **crew cab sonoma** » Thu Oct 18, 2007 5:37 pm

sorry... couldnt resist.

but if your bypass valve equipped stat stuck closed, would you not be facing the exact same situation???

theres no reason why the non-bypassing stat would be any more prone to sticking closed, than the the bypass equipped one...

green02crew · Post by **green02crew** » Fri Jan 04, 2008 7:52 pm

Ok so I have been looking over cooling options for a while as my truck can get hot but I can't seem to find anything to fit my needs. It doesn't get too warm here in the summers but when offroading I can get temps over 210 and that worries me. I would get a lower temp thermostat but the past 3 days I haven't seen temps over 10 degrees! The nights were all below 0. So are there any mods I could do to keep it cooler in the summer without freezing in the winter months?

Post by **HenryJ** » Sat Jan 05, 2008 6:08 am

Bigger radiator.

green02crew · Post by **green02crew** » Sat Jan 05, 2008 6:12 am

Haha that was a short and sweet answer! That will keep the temps down in the summer closer to the 190 mark? Does that also add extra cooling capacity to the transmission? That sounds like a great idea because that way my truck will still get to temp I must have skipped over that one in the list for some reason thanks!

green02crew · Post by **green02crew** » Sat Jan 05, 2008 6:16 am

Oh and one other thing I was looking into what you had and would a larger alternator help with cooling? When mine goes I'll most likely be upgrading it to the larger one but I just was wondering if that would make a difference or not with heat.

Post by **HenryJ** » Sat Jan 05, 2008 6:22 am

green02crew wrote:That will keep the temps down in the summer closer to the 190 mark? Does that also add extra cooling capacity to the transmission?

No and No.
The thermostat regulates the temperature. Stock is 195°. The range is usually +/- 10° of that depending upon the system and thermostat used. Having a sufficient supply of coolant and a radiator that will have enough volume and surface area to transfer the heat to the air efficiently will help to maintain a temperature closer to the thermostats rating.
The in tank sandwich style coolers for the engine and transmission may benefit from the coolant maintaining a slightly lower range, but likely will see little difference.
With the extra capacity you will see no difference, except in those times where the heat is excessive and the additional capacity is needed. This will just help to keep the temps from crawling over that 210 mark.

To lower your operating temperature you need a lower temperature thermostat and engagement point for the fan.

green02crew · Post by **green02crew** » Sat Jan 05, 2008 6:33 am

Ok thanks for the info on that one. I'll probably look into that along with the alternator when they begin to go/leak unless heat becomes a really big problem but as of now I have been able to deal with it.

Has anybody ever noticed that after running your truck for a while you turn it off wait a minute or two then turn it back on the temps are really high? I noticed this after going to work at the top of a huge hill I would turn off my truck to clock in now I leave it idling to keep coolant flowing. Just mentioning that because it scared the $#!t outta me!

Post by **HenryJ** » Sat Jan 05, 2008 6:37 am

That is called heat soak and a normal condition. Once the coolant circulation from the radiator resumes the temperature seen at the sending unit decreases.

border man · Post by **border man** » Sat Jan 05, 2008 3:23 pm

On the same topic, since arriving here in Roswell, NM I have noticed that my temp gauge reads pretty low. I think my stat may be stuck open. I want to replace it, but the GM dealers here in town are closed when I am off work and weekends. I need the AC/Delco part number (to order online) as I would like to stay OEM. 105,000 miles and counting. My heat works, but it is not scorching hot as it was in AZ.

Post by **HenryJ** » Sat Jan 05, 2008 3:31 pm

Courtesy Rockauto.com: 12597583

Rockauto wrote:ACDELCO Part # 131151 {#12597583}
THERMOSTAT,ENG COOL W/SEAL $11.02 AC Delco thermostat

GMpartsdirect.com wrote:GM PART # 12597583
CATEGORY: Thermostat & Gaskets
PACK QTY: 1
CORE CHARGE: $0.00
GM LIST: $17.72
OUR PRICE: $9.21

DESCRIPTION: THERMOSTA

Probably cheaper yet at your local AC Delco dealer

roadrunner · Post by **roadrunner** » Sat Jan 05, 2008 6:56 pm

green02crew wrote: Does that also add extra cooling capacity to the transmission? That sounds like a great idea because that way my truck will still get to temp I must have skipped over that one in the list for some reason thanks!

The best way to add cooling to your trans is to add on an external cooler.

One can be had at any NAPA or other auto parts store. when it comes to trannies cooler is better.

Fluid lubricity suffers greatly at higher temps and goes completely away at much lower temps than you might suspect. I currently have on on my CC with a 17,500 GVW rating cooler.

Overkill, Maybe maybe not but I like my gearbox cool. Never have trouble with trans temp even in heavy mud running.

green02crew · Post by **green02crew** » Sat Jan 05, 2008 8:39 pm

I was looking into one but I rarely tow more than 5k lbs and it takes a good amount of time for my transmission to get up to temp. It doesn't let it into 4th until its warm? Feel free to argue that but it feels that way. Anyway I read somewhere they do need to be run around the same temp as the engine to perform correctly. I could be wrong feel free to correct me!

roadrunner · Post by **roadrunner** » Sun Jan 06, 2008 3:49 pm

green02crew wrote:I was looking into one but I rarely tow more than 5k lbs and it takes a good amount of time for my transmission to get up to temp. It doesn't let it into 4th until its warm? Feel free to argue that but it feels that way. Anyway I read somewhere they do need to be run around the same temp as the engine to perform correctly. I could be wrong feel free to correct me!

I rarely tow anymore either but still wouldn't be without my external cooler.

It takes my truck about 4-5 miles in 0-20 degree temps to warm trans to the point it shifts all the way up. Yes mine doesn't do that final shift until warm but it isn't into 4th I can watch the tach drop for each shift and the final one that won't go until warm is the convertor locking. Produces about a 200-250 RPM drop when it shifts. Transmission fluid is much more easily damaged by heat than engine oil. Most engine oils won't degrade significantly until they reach temps which are 50-75% higher than what will render tranny fluid worthless. Don't just take my word for it, talk to any good transmission rebuilder or shift kit manufacturer such as B&M or Transgo they will verify what I am saying about trans fluid is true.

Post by **HenryJ** » Fri Feb 08, 2008 2:33 pm

How to Design And Build A High-Performance Cooling System wrote:Cooling-System Tips
While the cooling system may seem simple, consider not only the variables of coolant flow, airflow, and radiator efficiency, but also how other engine systems affect cooling. If the charging system is lame, your electric fan won't spin as fast. If the ignition curve is slow, that will affect cooling. We've assembled a series of tips and tricks that can often make the difference between an overheating monster and a docile street machine that can handle gridlock in 110-degree weather.

*Ignition timing has a direct effect on cooling-system performance. Retarded ignition timing begins the combustion process later in the cycle and makes heat. Initial timing numbers of 12 to 16 degrees and a curve that's all in by 2,500 rpm is a good starting place.

*An electric fan placed on the engine side of the radiator (as a puller) is always more efficient than a pusher fan. However, additional airflow can be created by using a second pusher fan on the front of the radiator.

This '57 Chevy's builder went to extraordinary lengths to ensure that all the air entering the grille would travel through the radiator. Building small-block off-plates between the radiator and the core support to direct all the air through the radiator will accomplish the same thing.

*Third-generation ('82-'92) Camaros came with an airdam placed directly under the radiator, which on older, high-mileage cars might be damaged or removed. These airdams are essential to create a low-pressure area behind the radiator to move air through the radiator.

*Jason Schmidt is an engineer with Spal, and he told us about a customer who had connected the power wire for a large electric fan directly into his fusebox. When large fans start, they can pull as much as 80 to 100 amps for 0.10 second. This large current draw pulled the voltage down far enough that the engine died. Wiring the power lead for the fan through a relay that sources power nearer the alternator cured the problem.

*The ideal tip clearance for engine-driven fans is 11/42-inch with the fan blade extending roughly halfway into the end of the shroud. This will create the greatest amount of air movement past the fan.

*Most engines are thermally more efficient at a coolant temperature of 195 to 200 degrees Fahrenheit. Pressure is also a critical function of coolant efficiency. A typical street-car cooling system operates at 15 psi. This pressure also increases the boiling temperature of water. As a rough rule of thumb, for every 1 psi of cooling-system pressure, the boiling point of straight water will rise between 2 and 3 degrees. Water boils at sea level at 212 degrees Fahrenheit, but at 15-psi gauge pressure, water boils at 250 degrees Fahrenheit.

roadrunner · Post by **roadrunner** » Fri Feb 08, 2008 3:24 pm

Ignition timing has a direct effect on cooling-system performance. Retarded ignition timing begins the combustion process later in the cycle and makes heat. Initial timing numbers of 12 to 16 degrees and a curve that's all in by 2,500 rpm is a good starting place.

Hey HJ! On my 01 CC 4.3 is this the correct base timing? If so, could you define your term of "all in by 2500"? Total degrees would be helpful to me.

Post by **HenryJ** » Fri Feb 08, 2008 4:36 pm

You have little if any control over the timing on your truck. The PCM controls ignition timing.
It all depends upon the specific engine. I like my big block to have no more than 10 degrees initial. I usually start there. I shoot for around 34 degrees total. As I said that is not specific. Each engine is different.
"all in by 2500" refers to the point where all the available advance is achieved.
This is easier to explain using an older system as an example: Add up all the advance desired. Initial advance is at idle with no vacuum advance function. Lets say 8 degrees. Add to that vacuum advance, lets say 13 degrees. Vacuum advance is kind of a misnomer. It is really sort of a vacuum retard as it disappears when you hit the throttle and advances as the vacuum returns.
Anyway, we now have 21 degrees. Next is mechanical advance. This is the fly weights in the distributor. We are shooting for a total advance of 34 degrees , so we need 13 degrees advance from the mechanical advance. The springs used determine how much centrifugal force is needed for them to overcome the tension and this is how the rpm is determined. All-in-by 2800 is my preference, so I choose springs that will be fully extended with the forces at 2800 rpm. Each of these can be altered. More inital, less vacuum, more mechanical. It is a balance. These simple systems offer lots of control and choices.

Once set you can not alter them while in service. That is where the brain of our truck is an improvement. It can make adjustments on the fly. Maintaining optimal timing, or at least trying to.
The PCM does all this. There is a formula that is used and readings from sensors are used in the calculation.

What control do you have over this type system?
Not much. You can change fuels to help eliminate detonation and the resulting timing retard. You can reprogram the PCM by flashing the chip with a programmer. You can alter the readings from the various sensors. This can be done by relocation, altering temperatures as is done with a lower temperature thermostat. There are also resistors that can be added to skew voltage readings. Sensor simulators are another device that might be used.

What is the "right" thing to do? Maybe nothing. Do you have a problem? Is there another way to fix it without altering the timing?
Remember to keep it simple. The most complicated answer is not usually the best.

green02crew · Post by **green02crew** » Fri Feb 08, 2008 4:38 pm

Most engines are thermally more efficient at a coolant temperature of 195 to 200 degrees Fahrenheit.

So does that mean we should all be keeping that 195 thermostat?

killian96ss · Post by **killian96ss** » Fri Feb 08, 2008 5:03 pm

Most engines make their peak power and run most efficiently in the 160 - 200 degree range.

Believe it or not you can run an too cold which results in a loss of power and gas mileage.

Heat expansion in the combustion chamber is what drives the pistons.

Not enough and you lose hp, while too much will do the same.

V8's seem to like the 160 to 180 range, while V6s' seem to like 180 to 200 degrees.

Every engine has it's sweet spot where it runs most efficiently.

A V8 generates more heat than a V6 and must dissipate it faster which is why V8's like slightly lower cooling temps than V6's.

I have personally seen a few V8's on a dyno make less hp when running anything colder than 160.

The Vortec V6 works pretty good with a 180 t-stat.

The 140 to 160 degree t-stat's are too cold for this engine unless it is used in a marine application (boat motor).

Brule is pretty knowledgable about cooling systems, so if any of this doesn't make any sense I'm sure he can explain it better.

Steve

Post by **HenryJ** » Fri Feb 08, 2008 5:10 pm

It might. Keep in mind that that is a range. A thermostat starts to open before the rated temperature and is fully open allowing the temperature to climb above that rating.
I usually figure about 10° either way. A 195° thermostat will run at 205° or so fully open on a hot day. A 180° thermostat will run at 190° or so on a hot day. That is if the system will maintain that.
Would 195° be optimal or even 200°? Perhaps.
What is the maximum temperature you want to see when the system can not keep up? I get pretty worried at 230°. That is only a 30° difference. Dropping the operating temperature 15° gives me a little more leeway.
I wanted to lower the engine temperatures for many reasons. One of which was to give me a little more room. I don't like riding so close to the edge.

green02crew · Post by **green02crew** » Mon Jun 09, 2008 1:06 pm

I can say today it was a record, nearly 100*. Truck stayed at a great temperature about 177. I was very satisfied. However, when I run the A/C temps rise and do not fall until I turn the A/C back off. Not fast but steadily and does not level out.

Thoughts?

Post by **HenryJ** » Mon Jun 09, 2008 2:04 pm

green02crew wrote:Thoughts?

177 is too cold. The thresold is 178. It will set a light.
If it does not cool or maintain at highway speeds, then you need a larger radiator. If it is just when you are not moving you need more air flow.

The stock fan does not engage until 220-235. Your temperatures will rise until the fan starts pulling. The lower stat just means it is fully open sooner. From there the radiator and airflow takes over.
I changed the point at which the fan starts pulling by going to electric fans. As far as I know there is not a colder clutch for our engine driven fan, so that was my solution.
The Exploder fan may be an option for a lower engage? I don't know for sure.

Remember the colder stat does not mean a colder running engine unless the system in place to dissipate the heat is adequate and matched.

F9K9 · Post by **F9K9** » Mon Jun 09, 2008 2:34 pm

Well, I washed the CC last night reconnected the battery and drove it today. 95°+ today. Temps went over 210° before I arrived at work. Shut it off and didn't hear the fans' running the normal 30 seconds after switching the key off. Investigated it and found a ground loose. Brule, can you wiggle your top left spade on your VSC and see if movement is there? I am now wondering if, something is broken inside the unit. Mine wiggles side to side but, it may be the nature of the beast. Thanks,
Reed

Post by **HenryJ** » Mon Jun 09, 2008 3:45 pm

f9k9 wrote:...can you wiggle your top left spade on your VSC and see if movement is there? I am now wondering if, something is broken inside the unit. Mine wiggles side to side

The connector can wiggle a little but the spade in the VSC is solid.

green02crew · Post by **green02crew** » Mon Jun 09, 2008 4:47 pm

I have made all mods to the cooling system with the exception of e-fans. It runs great till the a/c is turned on then temps begin to rise even with good airflow but not to scary high numbers just around 205 depending upon what I am doing.

I have not set a light yet with the 180 t-stat. It has been installed for months now and rarely runs at 180 but rather just below usually 177.

Post by **HenryJ** » Mon Jun 09, 2008 4:51 pm

green02crew wrote:I have made all mods to the cooling system with the exception of e-fans.

What have you done? I didn't see anything except a thermostat mentioned.

Running up to 205 with the AC on in 100 degree temps sounds pretty normal to me

04crewvt · Post by **04crewvt** » Mon Jun 09, 2008 4:54 pm

New scan gauge II showing my rig running right at 197 today at highway speeds which is a little less than the stock gauge shows, not too shabby at 70 mph, 93 degrees and a/c on max. Guess I don't have to worry about cooling mods yet on my rig.

Post by **HenryJ** » Mon Jun 09, 2008 4:57 pm

93 degrees and what for humidity?

04crewvt · Post by **04crewvt** » Mon Jun 09, 2008 4:58 pm

currently 84%

Post by **HenryJ** » Mon Jun 09, 2008 5:23 pm

Yeesh! We are in the comfortable teens. This year has been very cool , thus far. Highs in the seventies.

F9K9 · Post by **F9K9** » Mon Jun 09, 2008 5:57 pm

HenryJ wrote:.........The connector can wiggle a little but the spade in the VSC is solid.

Okay, then the unit is bad. I still haven't performed the precat recommendation but, I will. I am looking at the 2 VSCs . I cannot locate the instructions for the high end model but, may need to be walked through the npt connections. You know my limitations so, let me know which one to pull the trigger on. You're always my Hero

Post by **HenryJ** » Mon Jun 09, 2008 6:55 pm

If I had to buy one today, I would buy the Flex-a-lite 33054

This is rated at 40-45 amps. You no longer attach the fan , power and grounds with spade connectors. Wires are part of the unit. Solder and heat shrink the attachments. That is an improvement.
This VSC was not available when I bought mine, or I would have had this one.
It is $1 less than the other and does not include all the extra wire and fluff.
Still at $95 it is a pretty good chunk of mod money.

F9K9 · Post by **F9K9** » Mon Jun 09, 2008 7:39 pm

HenryJ wrote:If I had to buy one today, I would buy the Flex-a-lite 33054.......................Still at $95 it is a pretty good chunk of mod money.

Pulled the trigger tonite. Will PM with any mod questions. Soldering is not my "thing" but. will try again. Pumped the salesman for extra sale items since, I hate their handling charge. No dice!

green02crew · Post by **green02crew** » Tue Jun 10, 2008 2:57 am

Sorry I hadn't mentioned it as well above, but yes 180 t-stat, larger radiator, some water wetter, tranny cooler and some other things were added within the year. I was just a little freaked by the higher temps, I get used to 180 and 200 all of a sudden seams high.

Post by **HenryJ** » Tue Jun 10, 2008 3:32 am

Getting the fan to engage sooner is the key to keeping the engine temperature lower in your case.

F9K9 · Post by **F9K9** » Thu Jun 12, 2008 5:23 pm

Brule, I replaced the VSC this evening. When I removed the upper left ground from the male connector on the VSC, the spade came out with it. I can see why they made a design change. Now, I know I asked you this question before and I cannot relocate it. My set up is exactly like yours. The A/C connection to the VSC came loose during my transfer of wires. Does it plug into the A/C pos or neg location (#7 or 8 )? Thanks!

Post by **HenryJ** » Thu Jun 12, 2008 5:36 pm

Mines on #8