Another Cooling Mod thread. Bigger Radiator? E-Fans? IAT?

fallvitals · Post by **fallvitals** » Sun Jun 20, 2010 6:02 pm

Okay. Im going to start tackeling the cooling mods now. My crew runs WAY hotter then my old 96' 4.3 2wd regular cab s-10 did. I still find that odd since my 03 crew is essentially the same truck. Same parts, layout, etc etc.

I have done lots of searching, but lets start with what im seeing. Once temperatures are 90+ here with AC on my truck will run 210o fairly solidly if at interstate speeds. Now put me in the city and it will raise to 225, sometimes close to 230. Turn the AC off, and it will run 200-210 but im sweating my ars off.

I am taking a 8 hour trip to Myrtle Beach in my crew at the end of July and would like to not have to run without AC there and back, lol. So lets start schooling me.

#1 Jet 180o 10171 Thermostat

I have a Stant 180o in my truck now. From what im reading the Jet has a Bypass in it? but I dont really understand what it is, or how its helpful? I am gonna order it tonight, it will be the first part of my mod.

#2 IAT relocation

I have read this will help with the PCM reading cooler, or something like that, in effect it will help the truck run cooler, and the sensor will read 20-30o cooler after the relocation. Which will be in the bottom of the air box on the intake side, correct?

The mod page says the guy used a relocation wire kit for $40 from jegs ( http://www.s-10crewcab.net/og1/modinfo/iat/iat.htm )But he had a cold air set up. With the stock air boxes, will this reach without the relocation kit, or do I need the $40 kit?

#3 Bigger Radiator

I saw some other threads on this from the last year or so... it seems the bigger radiator is now not? The Vista Pro 431405 radiator is now only 1" thick, same as stock. I read about the napa radiator only being 1 1/16"? Is there any longer a thicker core radiator available? I couldn't find a solid answer while searching.

#4 E-Fans

Now this is a interesting subject. It seems all the install threads were lost with the crash of the old forum. But wait! I decided to search under Brule's web page and found his nice install guide:

http://www.s-10crewcab.net/HenryJ/fans/fans.html

I also found this page googling, looks helpful as well.
http://www.mys10truck.com/96/spal_efan.html

So, looks like the LS1 will definantly work, and the Spal 11 fan kit could work as well (in the second link). Looks like I will need the Flex-A-Lite Variable Speed Control to wire it in.

So.. all that sound about right? If there is no longer a bigger radiator, would those other 3 mods work? And just how effective are the e-fans vs clutch fan? Big time cooling improvement? I think I read its a big drain on the electric system so no improved MPG, but I do have the bigger alternator and diehard platinum battery now to power it.

I wanna get the Jet and IAT done soon, so I can see what kinda differance that makes and go from there. But, looking to be sure im on the right track, if that radiator still exists, and any pearls of wisdom.

fallvitals · Post by **fallvitals** » Sun Jun 20, 2010 6:24 pm

And this looks like the correct VSC? http://www.summitracing.com/parts/FLX-31165/?rtype=10

Really pricey.....

This LS1 is the only assembly I can find on ebay,

Looks a little different this Brule's... Little worried about how well it will hold up if I have to trim it like Brule did since it has some cut out areas.... (im sure I will have to). Its $160 shipped, buy it now...... seems steep also but the only one.

What kinda improvement would you all guess I will see with only the JET and IAT relocation?

Jongo88 · Post by **Jongo88** » Mon Jun 21, 2010 4:11 am

I just replaced my radiator 5 months ago. I got mine from jtr and it is the thick one. It was like 150 shipped.
As far as fans. I have an intreped duel fan on my crew. You can get them all day at the junkyard.. I paid 15 bucks for it and it fits like it was made for the s10.
I too run the Jet 180 stat. My temps never go over 200. Mostly stay 190 but when I pull my bass boat at 80 mph it will sneek up to 200 at the first stop. After that it will stay at 190.

fallvitals · Post by **fallvitals** » Mon Jun 21, 2010 4:42 am

My problem is I don't have time to search thejunkyards. I'll have to find time during the day to call and see if want are open on Saturdays. I'm no sure if I can afford a new radiator or fans before the trip, definantly not both. But which would be the better one to get for running cooler?

Jongo88 · Post by **Jongo88** » Mon Jun 21, 2010 5:07 am

The thicker new radiator would be you best investment.

Jongo88 · Post by **Jongo88** » Mon Jun 21, 2010 5:11 am

This is the one I have...
http://www.jagsthatrun.com/Pages/Parts_ ... r-134.html

fallvitals · Post by **fallvitals** » Mon Jun 21, 2010 5:27 am

Thanks for the info, how hard is it to replace the radiator? I don't think it will be bad I'm just am unsure what actually holds it in?

Jongo88 · Post by **Jongo88** » Mon Jun 21, 2010 5:51 am

It is very easy to replace it takes about 20 min taking your time. You have seven bolts and six hoses. Very easy. With all the stuff you have done to your truck this is nothing..

fallvitals · Post by **fallvitals** » Mon Jun 21, 2010 6:04 am

Any reason you didn't wanna use a does clutch fan instead of fans lime the radiator sight suggests?

Jongo88 · Post by **Jongo88** » Mon Jun 21, 2010 8:58 am

I went to an E-fan when I did the body lift. The clutch fan sitting two inches lower is just not as efficient.
Every cool thing you do to your truck like Body lift, Bigger tires and tranny cooler adds more heat. The stock radiator just is not enough to cool your truck any more. When you do one mod you will have to do three more to make it work right...
I say that because I did the body lift.. Then I had to do the e fan. Now I need more power for the e fan so now I had to get a bigger alternator. It all adds up in the end..lol.

fallvitals · Post by **fallvitals** » Mon Jun 21, 2010 2:02 pm

I see what your saying. Doesn't sound like a hard install. Is it a exact replacment other then being wider at the core, no contact issues? Hoses won't reach because he's are slightly off?

Do you think with only the new radiator, jet, and oat relocation I should be running cool enough to not worry on my beach trip till I get around to the efans?

Jongo88 · Post by **Jongo88** » Mon Jun 21, 2010 3:14 pm

It will fit just like the stock one.
Yes I think you will be good to go with just the radiator as long as your clutch is still good on your fan.... The thermostat will help too.

fallvitals · Post by **fallvitals** » Mon Jun 21, 2010 5:01 pm

Sounds good. Now that you made me think of it, the ford fan idea wouldnt great for us, atleast those with a Body lift. I didnt even think about the fan being displaced 2" now.

I thought Brule woulda chimmed in, but I think hes on another "vision quest" in another desert, lol.

Should be my last question, reguarding e-fans... are they pretty much equal? Brule used a LS1, you a Dodge intriped, will pretty much any (name brand, oem stuff, take off parts at junkyards assuming its not broke) dual fan with shroud work? Thats kinda what im getting from this? But still wanna be careful when purchasing.

Jongo88 · Post by **Jongo88** » Mon Jun 21, 2010 5:15 pm

I picked the intrepid fan because it fits like it is made for our trucks. It is a duel two speed fan.
Some guys like the Ford Taurus fan. It is a single two speed fan. It fits good too.
The ls1 fan has to be cut down to fit. It is to big to fit fit without modding.
I'm old and lazy so I went with a fan that fits.
I have a Ford Taurus fan in my Jimmy and it works good.
I have the intrepid fans in the crew and it works too.
The one thing I like about the duel fan is if one burns out you still have the other one to get you home.
Keep in mine you will need a fan controller to operate your fans.
I like the vsc controller (http://www.summitracing.com/parts/FLX-31165/). I have them in both the crew and the Jimmy.

fallvitals · Post by **fallvitals** » Mon Jun 21, 2010 5:44 pm

You say its made like it's to fit our trucks. So, how did you mount it vs the way brule did his except for cutting the top of the efan shroud? You still had to cut the s10 fan shroud and use angle iron to attach it right?

Jongo88 · Post by **Jongo88** » Mon Jun 21, 2010 5:54 pm

No angle iron.... lol. I cut the stock top shroud strait across and removed the bottom one. I cut a piece of aluminum stock 1 inch wide 1/8 inch thick and about two inch long like a tong to fit in the center hole where the bottom shroud fit. On the top of the radiator there is two cut outs about three inches from each end. I drilled a hole in the new fan shroud to line up with the cut outs. I put a 1/4 20 bolt about 3/4 of an inch long in each hole to hold the top.

fallvitals · Post by **fallvitals** » Mon Jun 21, 2010 6:18 pm

Looking at the radiator, i see the cut outs your talking about. But i not sure how you secured the top? you drill a hole in the fan shroud, put bolts through it, and what, do those bolts just set in that cut out.... no other fastener holding it there, or does the stock fan shroud when mount it just wedge it there?

They way im imaginging it, it will hold it, but it isnt truley secure?

Is this the same fan you have?

Jongo88 · Post by **Jongo88** » Mon Jun 21, 2010 6:45 pm

That is the fan I have. The weight of the fan pulls down. The tong in the bottom holds it from pulling back and the bolts and washers hold the top. Then the stock shrould goes over the top to keep it from going anywhere. It has been in my truck for about a year now. I run dirt roads at 60 and 70 mph. The dirt roads have a ripple so you have to go fast to smooth them out. lol. And take it in the mud and never had any problems with them.

F9K9 · Post by **F9K9** » Mon Jun 21, 2010 7:05 pm

I ain't touching this thread! You two are off and running!

fallvitals · Post by **fallvitals** » Mon Jun 21, 2010 7:39 pm

You didnt mention washers, but I think I'm creative enough to imagine washers setting behind the radiator, with a nut of course, to have to "hanging" there? Then the rest of it helps keeps it in there?

Now to just get the parts, lol. Thanks for the info jongo.

Edit. I wonder if one could use those zip tie with large flat stops, that come with tranny coolers, to hold it in place just as securely?

fallvitals · Post by **fallvitals** » Mon Jun 21, 2010 8:22 pm

I actually just found a used 99 intrepid fan, same as yours, for $66 shipped on eBay. Not as cheap as a junk yard, but not a bad price considering everything else I was seeing was 150ish, and I can't make it to the salvage yard due to work.

So, still getting the radiator, but I'm sure I'll get it all done before the trip, just need to get the vsc to finish it up.

Jongo88 · Post by **Jongo88** » Tue Jun 22, 2010 2:53 am

If you buy one online make sure you get the wire pig tail so you can wire it up...
The zip tie thing mite work if you cut half the ring off like a D shape.

Jongo88 · Post by **Jongo88** » Tue Jun 22, 2010 3:05 am

F9K9 wrote:I ain't touching this thread! You two are off and running!

Jump in any time bud... Lets see all options.....

fallvitals · Post by **fallvitals** » Tue Jun 22, 2010 4:49 am

I do like the zip tie thingy idea. Those things are tough and I am gonna need new ones for my tranny cooler any ways. I like that I know it's secure. If you break one of those you probably have bigger problems, lol.

That vsc is alot more then I ever woulda guessed! Cheapest I found is about 90 shipped on eBay. But I Will have to get that in a couple of weeks. I just thought that was a good deal on the fan for eBay. Ordering the radiator Thursday.

Jongo88 · Post by **Jongo88** » Tue Jun 22, 2010 7:31 am

I know the vsc is a lot but the cheep ones suck. I tryed one and had to break down and buy a good one....

fallvitals · Post by **fallvitals** » Tue Jun 22, 2010 2:30 pm

I'm pretty Cretan the fan has the lead wires, I'll post a picture from the auction. It looks like it did but was a bit shaky. I made sure to look for that.

Oh I'm getting the flexalite $100 vsc,,, something like that you don't wanna save a few bucks on, lol.

Another question, with that vsc... If it's pretty hot when turned off will the fans stay on for a few more minutes like some vehicles do?

dozer1530 · Post by **dozer1530** » Tue Jun 22, 2010 4:03 pm

dose anny one know a website i can buy the electric fans and radiator i need to convert my to eletric

dozer1530 · Post by **dozer1530** » Tue Jun 22, 2010 4:20 pm

i found a 12 inch and programmer for like 150 at orilys. the programmer works like you just set the on and off temp and it comes with a prob that goes in the radiator. will that fit????

Post by **HenryJ** » Tue Jun 22, 2010 4:34 pm

A 12" fan is not nearly enough. Two with a good shroud will work. The cheaper mechanical thermostats are trouble. Avoid them.

dozer1530 · Post by **dozer1530** » Tue Jun 22, 2010 4:36 pm

so is the a web site you recommend me to get what i need from

Post by **HenryJ** » Tue Jun 22, 2010 4:45 pm

How much do you want to spend?
I know of at least one V-8 running the Flexalite 210 fans. I think the OEM LT1 / LS1 fans are a better choice. I am not sure there is a perfect kit available.

dozer1530 · Post by **dozer1530** » Tue Jun 22, 2010 4:50 pm

iv got like 3 to 400 and i have a 2003 4.3 zr5 what can i get for that

dozer1530 · Post by **dozer1530** » Tue Jun 22, 2010 4:59 pm

im not the best at this kind of stuff but i can spend up to 400 for every thing like fan and shroud ect

Post by **HenryJ** » Tue Jun 22, 2010 5:15 pm

Probably check out the 210 fan kit then.

dozer1530 · Post by **dozer1530** » Tue Jun 22, 2010 5:20 pm

the 12 inch one right?

Post by **HenryJ** » Tue Jun 22, 2010 5:23 pm

You need a minimum of dual 11" fans. Keep in mind that this will just be the start as you will need a bigger alternator to power it and a stat to match it and the ball keeps rolling.
Plan on spending closer to $700 over the counter.
$400 for used parts and a new controller.

dozer1530 · Post by **dozer1530** » Tue Jun 22, 2010 5:29 pm

ok ty very much ill see what i can find

Jongo88 · Post by **Jongo88** » Tue Jun 22, 2010 5:51 pm

fallvitals wrote:I'm pretty Cretan the fan has the lead wires, I'll post a picture from the auction. It looks like it did but was a bit shaky. I made sure to look for that.

Oh I'm getting the flexalite $100 vsc,,, something like that you don't wanna save a few bucks on, lol.

Another question, with that vsc... If it's pretty hot when turned off will the fans stay on for a few more minutes like some vehicles do?

Yes they stay on for about 30 seconds. That is the main thing you don't want skinp on... Trust me on this one...

fallvitals · Post by **fallvitals** » Tue Jun 22, 2010 6:15 pm

Well looks like im good to go, once I get everything. heres the one I just got, looks like the wiring is there.

Jongo88 · Post by **Jongo88** » Tue Jun 22, 2010 6:23 pm

Yes I see the wires. Now that I look at it I remembered... See the mounting tabs on the sides? You have to cut them off. Just make a strait cut on them. Then you are good to go.

fallvitals · Post by **fallvitals** » Tue Jun 22, 2010 6:47 pm

I was thinking I would need to do that, lol. I just looked at some GM repair manuals, and the whole thing looks like it will be easy, hard part is parting with the cash, lol.

Jongo88 · Post by **Jongo88** » Tue Jun 22, 2010 6:50 pm

I know that..lol. Some times the stock fan is the hardest part getting off...

fallvitals · Post by **fallvitals** » Tue Jun 22, 2010 6:53 pm

lol, i know! The water pump died on my old 97 4.3 2wd s10. Hardest part was that stupid fan! I tried all the "right ways" after hours of tryig and a trip to the parts store for a special tool (got a ford tool they said would work, it didnt, but the wrench was the correct size).

I stuck a BIG flat head screw driver with the square shaft between two of the bolt heads on the "bell" overtop the water pump, moved it against something solid, and the nut broke free instantly! I was afraid of "popping" off a bolt head doing that, but sometimes you gotta do it the redneck way, lol.

Jongo88 · Post by **Jongo88** » Tue Jun 22, 2010 6:55 pm

Some times you got do what ever works.... So you now know what you will be in for...

fallvitals · Post by **fallvitals** » Tue Jun 22, 2010 8:44 pm

The jet 561-61620 iat relocator... That's the correct one right? Websites say it for a 96-99 chevy v8?!

gocntry · Post by **gocntry** » Wed Jun 23, 2010 6:38 am

fallvitals wrote:The jet 561-61620 iat relocator... That's the correct one right? Websites say it for a 96-99 chevy v8?!

Yep That's The One I Was Using... Check Your Pm's Too

fallvitals · Post by **fallvitals** » Fri Jun 25, 2010 5:16 pm

Jongo,'do you know if you can just replace a fan if it fails? Looks like ya can but I'm sure as a oem part it's pricey, lol.

Jongo88 · Post by **Jongo88** » Fri Jun 25, 2010 5:33 pm

You mean the fan motors???

Jongo88 · Post by **Jongo88** » Fri Jun 25, 2010 5:37 pm

Just a fast look

1999 DODGE INTREPID 3.2L 3200cc 197cid V6 FI (J) [EGW] SOHC : Cooling System : Radiator Fan Motor Wiki Price
VDO Part # PM9088
Radiator Fan Motor DRIVER SIDE - 2 WIRE CONNECTOR [Wholesaler Closeout -- 30 Day Warranty] (Only 4 Remaining)

$55.79
Add to Cart See Options at Left
VDO Part # PM9085
Radiator Fan Motor PASS SIDE - SHROUDS MARKED NMS, NMC, NMD [Wholesaler Closeout -- 30 Day Warranty] (Only 5 Remaining)

$69.89
Add to Cart See Options at Left
FOUR SEASONS Part # 75745
Radiator Fan Motor; Left Side; 3 Wire Leads

$102.79
Add to Cart See Options at Left
FOUR SEASONS Part # 75733
Radiator Fan Motor; Left Side; 2 Wire Leads

$131.99
Add to Cart See Options at Left
FOUR SEASONS Part # 75732
Radiator Fan Motor; Right Side; 2 Wire Leads

$165.79
Add to Cart

fallvitals · Post by **fallvitals** » Fri Jun 25, 2010 5:54 pm

Ya, motors. Are those oem replacements you copy/pasted? I searched eBay but only found aftermarket complete assemblys.

FYI I got my fan today, needs cleaned up. Alot heavier and better quality then I imagined.

Jongo88 · Post by **Jongo88** » Fri Jun 25, 2010 6:00 pm

You get the pig tail? You will like it. Today on the way home in stop and go driving with the ac on my temp never got over 191. It was about 98 out. My temp in the truck said it was 102. I never new it had three digets...

fallvitals · Post by **fallvitals** » Fri Jun 25, 2010 6:25 pm

Yup, came with the wire leads. I have the jet thermostat, now the fans, the IAT relocater should be here Monday. Radiator sometime next week, and I'll order the VSC in a week or two ten install the fan.

Jongo88 · Post by **Jongo88** » Fri Jun 25, 2010 6:31 pm

Sounds like a plan. I'm getting old so I went and took the top shroud off to see how I mounted the fan again. On the new raidator the cut outs I told you about are smaller. I did not use them. I drilled two holes and bolted the fan next to where the cutouts are.
A 1/4 inch hole and used two 1/4 20 3/4 inch long bolts to bolt it up.

fallvitals · Post by **fallvitals** » Fri Jun 25, 2010 7:03 pm

So what ya did was drill into that flap of material ontop of the radiator itself and ran thr bolt through it? I'm assuming with the fabbed tabs on the bottom ofthe fan there is no weight pulling down on top of the radiator? The top bolts just keep it from falling backward?

Aka, the top bolts aren't applying downward pressure that could possibly damage the radiator, correct?

So wow, once wired, that's about a direct bolt in, cool!

Jongo88 · Post by **Jongo88** » Fri Jun 25, 2010 7:22 pm

It won't hurt anything. They just hold it from falling back.

fallvitals · Post by **fallvitals** » Fri Jun 25, 2010 9:44 pm

Do you recall how you wires the fan itself? I was looking at he VSC diagram and am a little lost. Each fan has 3 wires, black yellow green. They converge and at thr main plug there are 2 black wires 1 yellow 1 green. How did you wire the +\- vsc to the fan wires?

Sorry for All the questions.

Jongo88 · Post by **Jongo88** » Sat Jun 26, 2010 2:56 am

The wires you need are the yellow and black. That is the high speed. The tan wire is the low speed and you don't need it. The vsc has a red and black. So the red goes to the yellow and the black goes to the black. There is a wire diogram that comes with the vsc.

fallvitals · Post by **fallvitals** » Sat Jun 26, 2010 12:31 pm

Great! Simple! Now let me also ask, where did you mount your vsc? I looked and can't find a good spot to mount it?

Also, my jet thermostat is in, almost. Took the bolts off anti freeze floods out, pop out the few month old Stant put in the Jet, and the bolt won't thread. I tried and tried..I look at it, the bolt had sheared off in the hole! That's crazy because I anti seized it a few months ago! I can wiggle it some with a crew driver so I know if I can grind the head I can unscrew it. With a 4 1/2" grinder I gently did it. And it screwed right out! Now I need to get a replacement bolt. Kinda of a PITA. Good news for reed those those ducks are a little farther north then Kentucky today! lol.

Jongo88 · Post by **Jongo88** » Sat Jun 26, 2010 12:37 pm

Pm me your e mail and tomorrow I will take some pictures on my install.
I have a hard time posting pictures on this site..

fallvitals · Post by **fallvitals** » Sat Jun 26, 2010 7:23 pm

I don't know much about radiators I do know the center is for coolant. The passenger side is the transmission cooler (I also have an additional transmission cooler), and is tr other side of it a oil cooler?

If I have that right, how much fluid from each will be lost when the change is made?

I imagine about all anti freeze, no problem.

When I did my tranny cooler, I didn't loose to much.

What about the oil cooler, if I am correct in assuming so? How much lost there?

This is gonna be a mess ain't it? lol.

border man · Post by **border man** » Sun Jun 27, 2010 1:59 am

The oil cooler does not run through the radiator. Only a little trans fluid, and all the coolant in the lines and rad.

Jongo88 · Post by **Jongo88** » Sun Jun 27, 2010 3:26 am

fallvitals wrote:I don't know much about radiators I do know the center is for coolant. The passenger side is the transmission cooler (I also have an additional transmission cooler), and is tr other side of it a oil cooler?

If I have that right, how much fluid from each will be lost when the change is made?

I imagine about all anti freeze, no problem.

When I did my tranny cooler, I didn't loose to much.

What about the oil cooler, if I am correct in assuming so? How much lost there?

This is gonna be a mess ain't it? lol.

It is not very much. I would guess you will loose less that half of a pint of oil and transmission fluid. The oil cooler is just like the transmission cooler. It just has bigger hoses and nuts that hold it on.

fallvitals · Post by **fallvitals** » Sun Jun 27, 2010 9:41 am

That doesn't sound bad.

The jet thermostat seems to have made a big differance by itself. I think my few month old 180o Stant thermostat may have gone bad? When I first got it, it ran 180s, I didn't think about it but slowly started to work it's way to running around 195avg even during spring?

I ran it a little yesterday in 92o weather with ac and it only ran 195-200 tops. About the best I got before was 210 in those conditions. I think it heat soaked once when I started it back up but it was only 215 (before it was around 230). And then the temp feel pretty fast. So, if it stays like it is now, I'll be good, and everything else will make it even better!

Post by **HenryJ** » Sun Jun 27, 2010 11:54 am

fallvitals wrote:... my few month old 180o Stant thermostat may have gone bad?

A 180 Stant thermostat? did it have the bypass valve? If so what part number. I have not been able to find any lower than the stock 195 with the correct bypass valve.

fallvitals · Post by **fallvitals** » Sun Jun 27, 2010 11:59 am

I still have the box in dads garage.. ill check it in a few minutes when I go over there. Atleast they told me it was a 180o... I should have the reciept somewhere to if i didnt toss it by accident... As for bypass, I dought it.. though im still not sure what exactly that is/does?

I compared the junk thermostat i had lying around vs stant vs jet, and couldn't see any distinct differances?

fallvitals · Post by **fallvitals** » Sun Jun 27, 2010 12:11 pm

The stant I have is a 195.... I know they told me it was 180 when I bought it.....

Post by **HenryJ** » Sun Jun 27, 2010 12:22 pm

I thought so. All the Stant I have seen are the stock temp range. The bypass valve is that washer thing on the bottom. It seals the bypass hole when the thermostat opens , directing all the flow to the radiator. In the closed thermostat position this allows the water pump to circulate water bypassing the radiator.
This was done in an attempt to cure the cavitation problems Dex has in our water pumps. They tried everything. The water pump was redesigned too.
Several have used thermostats that do not have a bypass valve. The problem is that when the stat opens there is noting to close the bypass port and there is a loss of flow to the radiator.
I have been watching for affordable replacement stats. I am running Jet and have Hypertech 160 in the garage. 160 is too cold, but I'm told that they make a 180 now.
As far as I know those are the only two lower temperature thermostats available with the bypass valve.

roadrunner · Post by **roadrunner** » Sun Jun 27, 2010 1:40 pm

Gonna have to disagree with you a bit on the reason for the bypass valve/block on thermostats. This is nothing new. I've seen thermostats clear back in the 60's with this feature. Investigation and inquiry of the engineers at GM and Ford alike comes up with the same reasoning for it and it has little if anything to do with the type of antifreeze used. It is a function of the warm-up of the engine. They wanted the coolant to circulate in the block to prevent hot spots and possible crack issues caused by them. Once the thermostat opens the flow is then changed and directed through the radiator and no further need to recirculate for even heating in the block. Many a DIYer in the past has had heating problems due to installation of the wrong thermostat (no bypass valve or improper size or too shallow when one is needed) causing heating problems and worse.

fallvitals · Post by **fallvitals** » Sun Jun 27, 2010 2:05 pm

Good info. For us, I'll say the bypass works. Did more driving in the city today. Truck said it was 98 outside. It got to 210, then waiting outside my grandmothers house it rose to 220 and stayed there all the way back to moms house. It was at 230 before under similer conditions.

I thought this might fix it for a second, but 220 is better then 230. I'll have everything else installed next weekend anyways.

Post by **HenryJ** » Sun Jun 27, 2010 2:10 pm

I will agree that it is not new tech. It is an old design used for a new problem. It is kind of hard to argue that it circulates through the block. It is just a short circuit from the front of the engine to the front of the manifold. Not a complete circulation through the engine block.
The 4.3L water pump created cavitation issues when used with Dex. The problems became apparent as Dex is sensitive to heat and air. The air bubbles formed by cavitation pose a problem. Reducing the pressure with a bypass was one of the things done to help alleviate this. The impeller was also altered.
The older 4.3L engines did not have the bypass and did not have problems. The marine engines do not either.

All the information was included in the class action law suit information. As this was seen as evidence of their liability. They deny there is a problem, yet they make changes to fix one.
I still have my paperwork somewhere. All the information listed on the website about the lawsuit has disappeared. I have had a hard time finding all the stuff about it as late. A little research on the early failures will highlight all the work they really did to try and make it work.
Let a sleeping dog lye ,I guess.

Jongo88 · Post by **Jongo88** » Sun Jun 27, 2010 3:46 pm

Just to let you know.. Not pictures yet because of the rain...
I will try tomorrow.

fallvitals · Post by **fallvitals** » Sun Jun 27, 2010 5:22 pm

Rain, thats no excuse! it was raining this evening and i still managed to put wax on my truck! Now im going to take it off, lol.

Thanks, I apreciate it.

Jongo88 · Post by **Jongo88** » Sun Jun 27, 2010 5:25 pm

Lol.. I had been rainning all dam day. It is 80% tomorrow too..

F9K9 · Post by **F9K9** » Sun Jun 27, 2010 7:23 pm

Jees-O-Pete, 72 posts and not one installed picture. WTF?

fallvitals · Post by **fallvitals** » Sun Jun 27, 2010 8:31 pm

lol, want a picture of my new thermostat Reed? I haven't gotten to the fun stuff yet.