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Trevor1980
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Does your engine have a problem overheating? Check this out!
« on: October 07, 2010, 10:02:35 PM »
my poncho 400 ran hot. I mean, it ran at 200F when I put in the new cam. On hot days, in rush hour traffic, the sucker would climb to 220F. One time, I had to shut it off in the middle of highway!
I heard everything, and TRIED everything. New Aluminum rad. All new hoses. Shroud installed. More coolant, coolant resevoir, new clutch on my declutching fan, I tried installing a flex fan, made it worse!
I tried fan spacers, to make the fan sit further in the shroud.. nope
Then I got into different thermostats. 160F, 180F 195F, I tried them all. Even the expensive high flow ones. Then I tried no thermostat, no good.
I bought an edelbrock water pump.
Did squat!
I was ALMOST ready to go with an electric fan, until I tried something totally different... I installed a poly foam between the shroud and radiator, to seal the gaps all the way around it. BOOM! The car went from 195F running temp to 165F!!
Can you believe it? I delt with this hot poncho for YEARS, and it was only because the air was bipassing the rad, coming in through the gaps between it and the shroud.
Before you spend all the money like I did, just install the darn foam! Cost $10, pretty comparible to the $800 for all the other garbage!
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1980 T/A 406 4WD 4Spd. 3.73
fb_rider
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Re: Does your engine have a problem overheating? Check this out!
« Reply #1 on: October 08, 2010, 02:07:58 AM »
I've had all of the same issues and pretty much did all of the same repairs as well. Mine's been better since I had the carb rejetted, but I still watch it closely. Can you post some pics? I'm not 100% sure what polyfoam is, or exactly how your installing it.
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1977 Trans Am SE w/W72 engine (sold)
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Trevor1980
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Re: Does your engine have a problem overheating? Check this out!
« Reply #2 on: October 08, 2010, 06:59:45 AM »
Where the shroud meets with the rad. The contact is all around, on 4 sides. I just put the foam on the sides, as the bottom is grooved, and the top bolts tight to the rad support. I had to customize my shroud a bit to accommodate for the new aluminum rad. The gap on 1 side was 3/4" and the other side was 1/4". Now I tried using my car wash sponges to seal it first to try it out, after my victory, I went to a commercial gasket store, and they had these foam blocks, which they cut for me to size. It's dense foam bricks. But would never melt, and tough, so I should never need to replace them..
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1980 T/A 406 4WD 4Spd. 3.73
mrbandit
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Re: Does your engine have a problem overheating? Check this out!
« Reply #3 on: October 08, 2010, 09:03:19 AM »
Never bypass the thermostat. That's asking for trouble.
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bandido
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Re: Does your engine have a problem overheating? Check this out!
« Reply #4 on: October 08, 2010, 11:34:48 AM »
Quote from: mrbandit on October 08, 2010, 09:03:19 AM
Never bypass the thermostat. That's asking for trouble.
whats wrong with bypassing the thermostat?its how i have mine and have no issues maybee you can make me think other wise.
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Trevor1980
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Re: Does your engine have a problem overheating? Check this out!
« Reply #5 on: October 08, 2010, 12:57:09 PM »
When bypassing a thermostat, the coolant flows about twice as fast through the radiator, giving the coolant less time to cool off. The thermostat actually slows the flow down, allowing the coolant to cool off in the radiator. Plus, the thermostat helps the car warm up quicker. If you drive the car often, this is noticible.
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1980 T/A 406 4WD 4Spd. 3.73
bandido
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Re: Does your engine have a problem overheating? Check this out!
« Reply #6 on: October 08, 2010, 01:27:21 PM »
Quote from: Trevor1980 on October 08, 2010, 12:57:09 PM
When bypassing a thermostat, the coolant flows about twice as fast through the radiator, giving the coolant less time to cool off. The thermostat actually slows the flow down, allowing the coolant to cool off in the radiator. Plus, the thermostat helps the car warm up quicker. If you drive the car often, this is noticible.
makes sense. Just never had issues since my car runs constant at around 180 even with an overdrive. Could it be my 4th gen ls1 duel electric fans are just that good
« Last Edit: October 08, 2010, 01:30:55 PM by bandido » Logged
mrbandit
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Re: Does your engine have a problem overheating? Check this out!
« Reply #7 on: October 08, 2010, 02:27:30 PM »
That is it exactly.
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80shaker
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Re: Does your engine have a problem overheating? Check this out!
« Reply #8 on: June 29, 2011, 01:26:29 AM »
I know this thread is old, but would any old foam style insulation work for this? I was at a hardware store today and found some heavier foam used for home heating and cooling. My only concern would be having it start on fire or melt. Would weather stripping be a better option if there's no commerical gasket outlet in my area?
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LeighP
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Re: Does your engine have a problem overheating? Check this out!
« Reply #9 on: June 29, 2011, 02:13:53 AM »
Stick a chunk of the foam on top of the engine...take it for a drive....check it a few times. If it doesn't start to melt or char...then it's probably temp stable. Foam sealing strip made for home heating etc or insulating hot water lines would probably work.
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Regards,
Leigh
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GEN II Racing Products - Australia
Tman
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Re: Does your engine have a problem overheating? Check this out!
« Reply #10 on: July 30, 2011, 07:45:27 AM »
Wow - good stuff here (and I got my 10 Smile
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BlueTTA
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Re: Does your engine have a problem overheating? Check this out!
« Reply #11 on: August 09, 2011, 03:33:05 PM »
Quote from: Tman on July 30, 2011, 07:45:27 AM
Wow - good stuff here (and I got my 10 Smile
Laughing SWEET!!! Welcome to TAC!
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You can get much farther with a kind word and a gun than you can with a kind word alone. - Al Capone
Chris
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1980 Blue Hardtop 305
1981 Brown Turbo Hardtop 301
blackfrontier
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Re: Does your engine have a problem overheating? Check this out!
« Reply #12 on: August 09, 2011, 03:56:05 PM »
I read in HPP magazine it's ok to remove the guts from a thermostat, but never run without one.
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Detroit Nemopie
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Re: Does your engine have a problem overheating? Check this out!
« Reply #13 on: February 26, 2013, 09:23:27 PM »
Nice tip. Just curious though, why the reluctance to put in electric fans? Less rotating drag.
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Street_Rodder
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Re: Does your engine have a problem overheating? Check this out!
« Reply #14 on: April 08, 2013, 07:09:14 PM »
Advanced timing on Pontiac's also cause overheating trouble......but the number one reason I have found is the wrong gap between the water pump propeller and the spacer plate which causes the water flow to miss the propeller at proper velocity.
There is a great thread on this on PY forums......
