Took my 350 SBC powered 1939 Buick out for its maiden voyage to the alignment shop today. Big problem....ran waaaaay hot ( my temp gauge shorted on the exhaust manifold, so I don't know how hot. The design of the stock front grille does not seem to allow alot of air passage through it and from what I read, it was always a problem. I added the biggest puller fan to the back of the radiator. A friend suggested putting an overflow can in the trunk with a fan on it! I can probably put a pretty sizable one of those stainless steele tubular versions on the side of the radiator, but not sure that would be enough. Anyone have any solutions that they know would work? Thanks
If it's an automatic plumb it to it's own cooler separate from the radiator. Fan shroud and engine driven fan usually works the best.
Move the temp sender out of the head and into the intake manifold, that will make a big difference. Try all the simple shit first, check the thermostat, make sure the rad is good, make sure the water pump is turning the proper direction, is the fan pulling air or pushing? If it didn't boil, how hot was it?
Be sure to use a fan shroud and seal the area around the radiator to force the air thru the radiator, also be sure the side vents on your hood are open to let the hot air out. GM had problems with these running hot also- the grill opening is small but beautiful. There were some aftermarket grills made for these that had different number of grill bars- might make some difference in the amount of air entering. Where is your fan in regard to the radiator- high, middle or low? Do you run a mechanical fan or electric? How large a fan? Original radiator or replacement?
Not sure if it would help your situation, but I had a problem with my 48 Plymouth/355 SBC running a bit hot at speed. Built an air scoop that hangs below the bumper, and forces more air into the radiator. Seems to work pretty well so far.
Thanks for all your suggestions, I don't have a regular fan, I have an electric pusher-fan with shroud on the back of the radiator. The engine is an '89 SBC that originally had a serpentine belt system but now has old-style individual belts and pulleys. If memory serves me right, I ordered an original style, but high flow water aluminum pump....do they make reverse-flow water pumps? Maybe I should check the box or call summit to find what I ordered....could I have a reverse flow water pump because I ordered it for an '89 SBC! I think I have about a 15lb. radiator cap, the radiator was new, using old tank by a radiator shop. Would an engine mounted flex-fan give me more cooling than my electric setup which is the largest size I could fit across the rad? I don't know what the exact temp was, because my S/W temp gauge sending unit wire shorted out on the header. I've been told to change it to the plug in the center of the side of the engine, down by the oil pan. Confused, any help would be great. Thanks
yes, water pumps can flow both ways check this out first. i usually run a mechanical when space allows, but electric fan should be ok. you got a thermostat in there? is it opening?
As said before, check all the simple stuff first. My girlfriends Pontiac had a temp surge from mid-range (approx. 180 0n stock gauge). Hit the thermostat housing with a no contact thermometer... temp was 139 degrees. R&R'd temp sensor, all is well.
Glad to hear that because an 89 SBC with serpentine belt would have had a reverse rotation water pump in it. Don't know why people ditch the serpentine belts, I have a 92 Chev 4.3 in mine, ditched everything I didn't need when I went from the EFI to a carb intake, but kept the serpentine system -- had to get a different length belt which now only drives the original reverse rotation water pump and the alternator (didn't even use a tensioner).
shouldnt need a ton of radiator for a 350, I run a $175 ebay aluminum unit in my 37 buick and I cant get the car over 180 unless sitting in traffic. Also you should have a puller fan if it is behind the radiator, not a pusher, so verify the fan is pulling air into the engine compartment or pushing it into the engine compartment if it is mounted in front of the radiator. This is the setup in my 37, 16" puller fan, reversable by switching the power leads. Fan doesnt come on until 190 degrees.
Have a puller fan mounted on the back of the radiator. Put paper behind it when it was running and it blew it back into engine area. It is mounted pretty much in the middle of the radiator a little above. Going to remove temp sender, put it on the bottom left side of engine, and also check the t-stat. Also going to add SS overflow 15"x3" cylindrical tank. Any other suggestions ?
In my particular case, my engine ran hot because the vacuum advance was frozen and it was always running retarded. I swapped distributors and that cleared up the problem. Because I was going to add A/C, I also swapped to a tri-pass, 4 row radiator from U.S. Radiator. A buddy of mine, with a chopped '49 Merc, had a problem with heat. He tried everything. Custom radiator with dual electric fans. He finally louvered his hood and that cured his problem. It also made the interior cooler. Good luck.
Timing is 6 degrees BTDC. Distributor is new and working fine. Even though I love louvers, it wouldn't be the look I want. I'd try a bottom "spoiler, air scoop" before that.
Do you have an accurate gauge? Can you feel the upper hose get hot when the thermostat opens to verify it is working? Overheats just sitting idle or when the car is moving as well? Many, many threads on this site about overheating that contain the basics and not so basic info.
Car overheated while driving on road, no traffic. Stewart Warner temp gauge had shorted against exhaust manifold and did not read. Did not feel hose at that time.
If you didn't have a working gauge, and did n't lay hands on the hoses, how do you know it overheated? Did it boil over or push coolant out the overflow?
Yes absolutely, it was blowing antifreeze out the overflow hose (I had no overflow tank, I'm putting one on now)
I'm thinking you're panicking over nothing, it was the maiden voyage, if you filled the rad, it would puke out till it found the proper level, thats supposed to happen, secondly, you don't know how hot it got, move the temp sender to the intake manifold, use the port beside where the thermostat is, the heads will read hotter, the block will read cooler where you want the sensor. Run a 180 thermostat, verify the guage works and do it again. I think you'll find there's nothing wrong.
At the point of shutting it off, it was blowing antifreeze, wouldn't shift(700R4 Trans)... after shutting off: wouldn't restart, , trans was full and smelled OK, no noise at all when key turned, I think fan still came on with key.
The air flow must be directed THROUGH the radiator core. Any area where air can pass BY , UNDER, or OVER the radiator core should be filled. Easy to test and see by using cardboard for deflectors and duct tape. or masking tape, to hold the stuff in place. This has solved many an overheat problem for me.
Replaced thermostat, took off corrugated steel rad hoses and replaced with smooth, rubber formed hoses. Am going to take cardboard and cut it to mock-up a fan shroud, then make it out of aluminum since i can't find anyone who sells them alone by themselves. And then i will put a fixed steel 6 blade fan on the wp pulley and save the electric fan as a last resort, if I need to put a pusher on the front. Fixing the temp gauge and then I'll be ready for another crack at it. This all happened while the car was traveling well with no stops in traffic, so I am reminded of my mechanic father's words that said if a car overheats while running , it's water flow, while standing still its airflow....?..
I like your father's quote...might be a bit general, but a good rule of thumb to start troubleshooting. Thanks for sharing.
I agree with you on this. just surfing for Buick info and came upon this heating problem. I have been into straight 8 Buicks for a long time and had the 39 heat problem also. Have a 39 Century sedan and it heated badly when I first purchased it. Driving it home from Provo Utah to Riverside Ca. out on the highway it got really hot and was boiling water bad [39,s dont have pressurized radiator]. I pulled off and drove around looking for a gas station and noticed it was cooling down. To make it short I kinda solved the problem by stuffing a couple of pieces of wood under the back of each side of the hood. I was then able to continue home as long as I kept it under 50 mph. Gads! Noticed also when at speed I stuck my hand out to see if I could feel the heat coming out from under the jacked up hood, it was really hot! So then decided it was the design of 39's as they dont have enough air circulation out of the engine compartment.[needs a louvered hood gggg] I looked around and found that the front crossmember actully acted as a scoop, thus directing air from under the car and behind the radiator and fan, the hot air was dammed up. Blocked out that area and added a missing shroud, it really made a difference.
I am thinking the lower crossmember has something to do with it. I am planning to make a hard rubber scoop?spoiler around it to direct air from under the car completely into radiator, and block off areas where air goes through crossmember and back under car. Unfortunately the season changed and I won't know the benefit until the weather warms up. I agree the car does not ha much place to displace hot, under-hood air but unfortunately louvers etc are not an option. Would like to keep exterior as stock appearing as possible. Thanks
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