Replaced radiator, have question

[BP]

I see no need in starting a new thread,and since Chili got his answers..... I have another radiator question. I have a 81 chevy truck that has a bit of an overheating issue. It over heats only in warmer weather when sitting at a long light or slightly heavy traffic. I put a brand new radiator in it as well as a new thermostat. It has dual electric fans and an electric water pump. Any ideas what could be the cause?

It's either the fans not being large enough, the tanks being too thin or you need a shroud. Or maybe the fans aren't coming on like you think.

[juiceweezl]

Are you sure the stat is opening? Try running it without a stat and see if it still gets hot. If it doesn't, then I'd say you have a bad stat. If it does, then you have fan issues.

You can check the stat in a pot of water on the stove. Put a thermometer in the pot and heat the water with the stat in it. Just note the temperature at which it opens.

[Doug Hatton]

I prefer pipe dope or liquid teflon in cases like that as opposed to teflon tape. Less likely to clog something up if a piece gets in the line.

[T-TOPPS5.0]

Are you sure both of those fans are kicking in? They're thermostatically controlled by a switch, that sometimes can go bad.

yes both fans kick in. I even hooked them up to come on as soon as the ignition comes on.

It's either the fans not being large enough, the tanks being too thin or you need a shroud. Or maybe the fans aren't coming on like you think.

I do not have a shroud on it. Would that really make a difference? The tanks? you mean I may need a larger radiator? As mentioned, the fans are set to kick in as soon as the key is turned.

Are you sure the stat is opening? Try running it without a stat and see if it still gets hot. If it doesn't, then I'd say you have a bad stat. If it does, then you have fan issues.

You can check the stat in a pot of water on the stove. Put a thermometer in the pot and heat the water with the stat in it. Just note the temperature at which it opens.

Thanks for the trick on how to check my stat. And thank the rest of you guys for other things to look for and pointing me in the right direction. I guess I'll start the process of elimination.

[Chili]

I prefer pipe dope or liquid teflon in cases like that as opposed to teflon tape. Less likely to clog something up if a piece gets in the line.

I thought about that, and have some pasty type pipe thread sealant, but I felt more comfortable with the tape. The way the connection is I don't think there was any chance of getting the tape into the system.

I do not have a shroud on it. Would that really make a difference? The tanks? you mean I may need a larger radiator? As mentioned, the fans are set to kick in as soon as the key is turned.

I have heard that no shroud will affect cooling, it helps to focus the air.

[kingjason]

yes both fans kick in. I even hooked them up to come on as soon as the ignition comes on.


I do not have a shroud on it. Would that really make a difference? The tanks? you mean I may need a larger radiator? As mentioned, the fans are set to kick in as soon as the key is turned.




Thanks for the trick on how to check my stat. And thank the rest of you guys for other things to look for and pointing me in the right direction. I guess I'll start the process of elimination.

You need a shroud. Take a pic of your set up and post it. If you have a true fan kit like flex a lite or such then they are built into a shroud. If you just mounted two fans to your radiator its not gonna work. Get ya an old taurus two speed fan set up out of the ole yard or off ebay. It will pull small birds thru the radiator. No offense to bird lovers.

[T-TOPPS5.0]

You need a shroud. Take a pic of your set up and post it. If you have a true fan kit like flex a lite or such then they are built into a shroud. If you just mounted two fans to your radiator its not gonna work. Get ya an old taurus two speed fan set up out of the ole yard or off ebay. It will pull small birds thru the radiator. No offense to bird lovers.

LOL... Actually you are correct. I dont think its a true kit. The fans were already on there when I purchased the truck. All I did to them was order the switch from summit. I will look into getting a real kit plus the shroud. I'll keep my eyes open for the taurus kit as well. Thanks again!

[donnie90stang]

Im gonna throw this out there just because I have been through it... Make suer the belt routing is correct on the water pump. I had a stang that that I traded for, and after several days of messing with it.... I noticed the clutch fan wasnt blowing any air in my face while leaning into to engine compartment. The water pump had been going backwards, and on a warm day it would overheat. Sounds stupid... but apparently it does happen.

[WildBill]

I see no need in starting a new thread,and since Chili got his answers..... I have another radiator question. I have a 81 chevy truck that has a bit of an overheating issue. It over heats only in warmer weather when sitting at a long light or slightly heavy traffic. I put a brand new radiator in it as well as a new thermostat. It has dual electric fans and an electric water pump. Any ideas what could be the cause?

It's a CHEVY!

Are you sure the stat is opening? Try running it without a stat and see if it still gets hot. If it doesn't, then I'd say you have a bad stat. If it does, then you have fan issues.

You can check the stat in a pot of water on the stove. Put a thermometer in the pot and heat the water with the stat in it. Just note the temperature at which it opens.

Running it without a stat can make it overheat by not giving it enough time for heat transfer to occur in the radiator.

yes both fans kick in. I even hooked them up to come on as soon as the ignition comes on.


I do not have a shroud on it. Would that really make a difference? The tanks? you mean I may need a larger radiator? As mentioned, the fans are set to kick in as soon as the key is turned.




Thanks for the trick on how to check my stat. And thank the rest of you guys for other things to look for and pointing me in the right direction. I guess I'll start the process of elimination.

Post up pics of the fan setup and the CFM they are rated for.

[91CoupeMike]

What size alt are you running?

In traffic with low rpms and a over worked alt, you'll have a lot of voltage drop. And cause the fans to spin slower.

Just an idea.

[kingjason]

The Taurus set up is not a kit. You can get the complete set up off ebay and then wire it. I cant remeber exactly what years it was on but go over to Pirate 4x4 and search there are a 1000 wright ups.