My '72 350 car has had cooling issues since I got it. It actually overheated and left me on the side of the road the day I picked it up.

So far I've installed a new 180 degree thermostat, an aluminum BeCool radiator and two of their biggest CFM electric fans and have made the problem much better.... After I worked through a couple dead batteries and upgraded the alternator thanks to the fans, but that's another story...

What I don't understand is why I still regularly see 210 degrees on very hot days in the summertime. I'm considering a hi-flow water pump next, but I'm wondering if there's anything else I should look at first.

What's everybody think?

 

hitting 210 on a hot day is not a problem. your engine isnt gonna explode because of it. if you started seeing 220 then i would start to worry

 

210 aint nuttin to worry about. make sure all your shroud and seal stuff is in place. rusty/deteriated water pump impeller fins maybe, water pump age?

 

Have you checked the actual temp of the engine with an I.R. gun? I had the same issue, I installed an aluminum radiator, dual SPAL fans set to come on at 195, a high flow modified 180 thermostat and an Edelbrock water pump. My guage was still showing ~210-220 when the fans would kick on. I checked it with an IR gun and the fan switch thermostat was dead on and the fans were kicking on at 195 and the engine didn't go over that. This is with a new temp guage sending unit. Might want to check that out before you freak out.

 

I've had good results with Mr. Gasket thermostats and so have others on here. That alone will make a difference in my experience. You could even get a 195 one. Get 'em at AutoZone. $8 and you can get a reuseable gasket while you are there...

 

I recommend before doing any parts replacement to check the timing and the fuel mixture, these things will impact the running temp. of the engine so much.

 

You would not belive the differance between a 180 and a 160. With a 180 i was limited to driving in the country, stoping it would climb quickly to 190-195 sit a couple more mins 200. I could not let the car sit to tune it up, it would run hot. (hot to me is 200). With a 160 it will sit an idle for hours if i want an stays on 160, i even removed the fan still runs 160 ( with electric fan) I ride all over town now no problems at all. Might want to consider a 160, it sure worked for me. I have a shoe box full of 180"s

 

Nonsense!!

The thermostat has NOTHING to do with how hot a car engine gets unless it is stuck closed.

 

If the thermostat has NOTHING to do with how hot a car engine gets unless it is stuck closed, maby they should stop wasting there time stamping numbers on them.

Not trying to start a debate, just saying he might want to try a 160, it worked for me with no other changes. Might work for him as well.

 

If the car will run at 160 all day with a 160 stat, it'll certainly run 180 all day with a 180 stat.

You're better off with a 180 stat. That's in the temp range where the engine was designed to run at.

 

The C3 radiator is slanted so it will fit into the front of the car. There is sealing foam between the top of the radiator and the hood to force cooling air thru the radiator instead of allowing air to flow over the top. If these seals and the air snorkels going to the air intake are missing. Your car will overheat. Your cooling fan shouildn't even be needed at highway speeds if the seals are in place and the air is being forced thru the rad. We have seen this a lot on C3s where the seals have deteriorated, been removed and/or the stock air filter assembly been replaced with an aftermarket brand. Replacing the seals and making sure no air can flow over and around the radiator fixed my problem. I hope it fixes yours!
Bernie

 

If you had the problem when you bought the car, checking the timing is a great idea. One other thing that gets overlooked is the functional front spoiler. Mine was missing when I bought the car, and it makes a difference. It scoops up nice cool air from the street and forces it over your radiator. It takes about 2 seconds to check and be sure it is there, if it is, you can move on.

As others have said, 210 is not running hot.

 

A thermostat sets the minimum temperature of the fluid that runs through the engine, and lots of other things effect the final temperature this fluid reaches when the engine is at some 'steady state' temperature:

Engine timing
Radiator efficiency
Air flow rate through the radiator
Ambient temperature / road surface temperature / humidity
Driving environment (highway vs stop-and-go)
Carb tuning (rich/lean)
Fluid level in the block
etc.

Add the additional variable of the gauge/sensor pair accuracy (which I have seen to drift based on the electrical load of the alternator), what you see is not necessarily what you get.

From my own experience, I've used a 160 stat in the summer of the Texas gulf coast (100+ ambient 125 road surface) and had 200+ indicated on the gauge verified by ir on the stat housing after an hour of daily commute. I've used a 195 stat and seen the same thing. The only difference is that with the 195 stat I reach this temperature in about 4 minutes, it takes about 10-15 with the 160 (unless it is below about 45 degrees outside when the gauge will stay below 200).

My cooling setup is completely stock, and I have the additional thermal load of an automatic transmission. I've never boiled over.

Always makes me wonder how much discussion there would be here if the gauges just had a C on one side and an H on the other....

 

If you don't have a fan shroud.......you will have cooling problems. All the newer model cars with electric fans have some sort of shroud around the fan. With the new rad you installed, you have ruled out any sort of inefficent rad problems...now you just have to use all of that new radiator.

 

Bernie is dead on. Most people do not realize that the foam seals, fan shroud, and air dam are all part of the cooling system just like the t-stat, fan clutch, surge tank, etc. It is best to include these when trouble shooting cooling system problems. I agree 210 is no cause for concern. I do think it's a little hotter than your combo should run, especially if you have a good t-stat such as the EMP or Robert Shaw high flow (always use the by-pass version). Do you see the hotter temps while idling, or stop light to stop light, or at sustained freeway speeds?

 

The NUMBERS also have NOTHING to do with how HOT the engine gets!

There IS NO debate - you have a completely incorrect understanding of how the "system" works.

 

Thank for all the good advice everyone!

Here's a little more information. The fans are in a shroud, but the shroud is only as thick as the fans. The seals are new and intact on the top and around the radiator. The mechanical fan and original shroud have been removed, there is no chin spoiler, and it's running a bugeye air filter. The timing and carb were set up by a buddy who's a pro during the course of the problem and didn't change the temp.

All this leads to two more questions:

At what temp should I start worrying?

What's the smartest next step considering the new information?

 

Well as pointed out above the temps your running are not bad at all. The T-Stat at 180 is fine, it sets the minimum temp on the engine. New Rad, new fans, new seals, MISSING SPOILER is not good, get that put back on immediately. Next make sure the lower radiator host is in good shape and has a spring in it. The lower hose is on the suction side of the water pump and will collapse without the spring. Cheap fixes.
The high flow water pump will not do you any good if the rest of the stuff isn't right. IMHO it should never be needed in a street car.. The cars worked fine when new right? So it should work good now. The reason it doesn't is some degredation in the system. Fix that and see where it gets you.
Good Luck

 

I run a stock cast iron pump on my 500 HP 385 motor and it does just fine. Get the chin spoiler and verify with an IR gun those are the actual temps you are running. The fan setup sounds OK. The temps are not out of the normal range by any means. I would start to worry about 220+.

 

220 on a hot summer day in stop and go traffic with the AC running would not freak me out. 230 for a few minutes here and there would be cause for concern, but if you have good coolant, it probably won't cause any harm in the short term. But I would be more vigilant about making sure the system was right. Above that, and you have a problem that needs to be addressed NOW IMO.