I have a 4 core aluminum radiator on my 55 with an electric fan pulling air through. I made a fan shroud for it that is less than an inch thick. With a 165 deg. thermostat it will still run up around 200 and sometimes a little over on a hot day. Would a deeper shroud help this or do I need a bigger fan? I thought the gauge may be off and it may be a little but on a cool night it seems to run about right.
Please don't beat me up too bad for the C#$&y engine,,I promise to do better some day.

 

Change to a high flow stat. Probably have a new engine as well, which generates a little more heat.

I spent months on an overheat problem that turned out to be a thermostat flow problem.

Sam

 

You may acquit yourself in Purgatory,LOL!

 

Chevy???

Ok, now that we have that out of the way.

What radiator do you have? What engine mods have you done? We need more details to give you better, informed answers. The lower temp thermostat won't necessarily have your engine run cooler. If you have a problem, all a lower temp stat will do is open sooner, and whatever issue is causing overheating is still going to be there.

It's also good to know what ambient temp you're running in. If it's 110F outside with 99% humidity, it's going to run warmer than normal, no matter what you do. That's just simple physics.

You've asked a lot of questions, but not provided many answers of your own. You asked if you need a bigger fan, but didn't say what you have in there now. You mentioned building a shroud, but it's unclear how you built it, and if it's working properly with the electric fan. Most electrics come pretty much self-contained.

We need details.

 

What quality of a electric fan do you have? There are a lot of EF out that that claim they are good and their not worth the plastic they use to make them. What brand is your fan? What model number?

 

Sorry for the lack of info. I have a chevy motor in a ford truck,,,how smart do you think I am??LOL
My fan is a 14" and I'm not sure of the CFM's ( My wife bought it at a car show "It was chrome" so I thought I would try it. The shroud is a sheet metal inclosure that covers the radiator and the fan is mounted on it the only way I know how. My concern is how close it sets to the cores. Would backing it up help pull all across the cores?
And yes it is abnormally hot and humid these days.
I just got the air working on the truck. That is another thing that has got me working on this. I'm almost affraid to run the air because of this.

 

Believe it or not, I've found that three row radiators cool better than four row! You can't get enough air through those four rows. You might as well get comfortable with the 200 degree temps because there is probably little you can do to make it run cooler. I ran a 4 row Walker in a 29 Ford (350 Chevy) with A/C years ago. I experimented with thermostats, fans, and shrouds to get it to run cooler with no success. Actually, if the ambient air temperature is around 90+ degrees and you're running the A/C, 200 isn't too bad. Mine use to run about 190-200 most of the time and would go up to about 220 in traffic....

 

I have a c***y motor in my 49. I have a 2 row radiator with the AC condenser as close as possible on the front of it. I have a 16" SPAL fan that blows about 2900 cfm. I also have a shroud on it. With the AC on and the outside temp at 100', I run about 195'. It ran hotter at 70 MPH than at 25 mph. Slow driving, the fan is pulling air across the whole radiator. At high speed, the air coming through gets choked in the shroud and can't get out, except through the fan. I put 10 rubber flappers in the shroud, that blow open at high speed and let the air out. Now it runs the same at both speeds.
I think your 14" fan is too small and the 4 row radiator with a AC condenser is causing too much restriction.

 

That's a nice looking truck. Unfortunately, your problem is unfixable, so I'll come on by to get that vehicle out of your way. I've heard four row radiators are hard to get air through them, so that might be your issue. Of course your gauge may be off; as that's the least costly to check, I'd start there.

 

I just bought the wife a 54 ford sedan this week and it runs about 190/195 on road and up from there in town so I started looking for a fix then I got the infer=red thermo out and it shows 180 and up to 195 in town so check your guage, Garry

 

I chased overheating gremlins on my 53 for some time before finally buying another radiator. Originally I was running a 2 row for a Dodge P/U and a 16'' electric fan, it ran pretty warm most of the time. Tried building a fan shroud and found that it ran much hotter because the shroud restricted the air flow. Tried a fan from Summit that had a built-in shroud, better but still not good. When I installed my A/C I installed a 4 row from Mid-Fifty with the original 16'' electric fan mounted directly to the radiator. Have no cooling problems now, even pulling my 1600lb teardrop trailer when it's 100* out and the A/C blowing cold

 

Lots of variables here....but speaking strictly from the fan point of view you should be using a fan that covers as much radiator surface area as possible. This usually means around 16 inches. Here are a couple of pics of a shroud with fan assembly that a guy in our club had fabricated. It is important to ensure that the shroud fills the core area of the radiator and that the fan fills the opening in the shroud. Any air that passes through the radiator core should also pass through the fan...openings/gaps in the shroud will reduce the effciency of the cooling setup. I used this setup with a 460 cuin engine and had no problems with cooling...and that was with a 4-core radiator.

That said, the size, the number, and the pitch of the fan blades also have a lot to do with how much air is pulled through the radiator. You did the right thing by using the fan your wife bought for you...now it's time to let her know that if she wants A/C then it might be time for a new fan. I have also seen a few trucks where the owner had installed a "pusher" fan in front of the radiator but that seems a little extreme to me.

 

The easy way to zero in on what you need is to try running without the shroud. If you still run a little hot in traffic, but OK on the hwy, you'll need a bigger (16") fan. Don't even think about changing the radiator. 4-rows rule with AC.