Howdy boys, a young fellow in our club has a '29 that has a problem of overheating that I can't help him with. Long story short, it's had two engines in it, and it continues to overheat. Timing is correct, water pump seems normal, radiator has been back flushed, along with the block, and it still overheats. He is going to clean the radiator with a coolant system cleaner and see if that helps, but I am doubtful, due to the cleanliness of the water when we flushed it today. The only thing I can think of is there must be a reason water is not flowing. Damned if I know. We've had the pump off and it seems to be in good condition. The radiator seems to flow normal, but I haven't measured gpm flow. Should be around 40 if I remember correctly. I guess we're going to have to pull the radiator and clean it out professionally, unless we can get it to flow better. Any suggestions, other than the obvious, would be appreciated. Thanks guys, always like to hear your thoughts.
Over heating. Can't figure this one out.
- Thread starter Seabees
- Start date
Big hammer
Well-known member
More information please ! What are the signs of overheating, what temperature and how it’s taken, at what parameters are you overheating, idling, slow speeds, highway speeds, etc
TerryH
Well-known member
If the radiator is truly plugged, backflushing will probably not clear it. I would strongly suggest having it rodded by someone that knows how to do it. When I bought my Model A 16 years ago, it overheated some, and I was directed to a gentleman who had lots of experience in rodding radiators. Afterwards he told me that something like 24 tubes were completely clogged, and he was able to successfully rod all but about 4. My car never overheats now.
BillCNC
Well-known member
If both engines ran warm, then it's either your timing or radiator or a combination of the two. With the weather right now, hot plugs shouldn't do it.
Test your radiator, it should flow 38 gallon in a minute. You'll find videos on Youtube explaining how to test it. Also, as Ray64 said. More than likely your timing is to far retarded.
Regards
Bill
Test your radiator, it should flow 38 gallon in a minute. You'll find videos on Youtube explaining how to test it. Also, as Ray64 said. More than likely your timing is to far retarded.
Regards
Bill
nkaminar
Well-known member
As Big Hammer said, what are the signs of overheating? Steam? Coolant discharge?
What is the age of the radiator. They do get old and loose the ability to cool. Rodding as Terry H suggested may help.
There are many possible reason for overheating. You will have to play detective to eliminate each possible cause one at a time. You have already done some of that by looking at the timing and fuel ratio.
What is the age of the radiator. They do get old and loose the ability to cool. Rodding as Terry H suggested may help.
There are many possible reason for overheating. You will have to play detective to eliminate each possible cause one at a time. You have already done some of that by looking at the timing and fuel ratio.
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ryanheacox
Well-known member
Another issue is if the fins get loose and the tubes can't transfer the heat to them efficiently.
Ernie Vitucci
Well-known member
Good Evening...A plugged muffler and or tailpipe might be part of the problem...also the head gasket could be loose...or warn out. It is also a good idea to take off the lower water pump inlet and the water pump and then insert a power washer nozzel into the botom water entry and fire away, then into the one in the head and do the same thing. I turned a driveway orange...Her magesty was not pleased. She did not smile at me. Ernie in Arizona
Chuck Sea/Tac
Well-known member
Buy a cheap ir temperature gun and shoot the radiator. That will tell you how well the tubes are transferring heat.
dave in australia
Well-known member
To see if the radiator is cooling efficiently, get an infared temp gun, and do few checks in various spots on the core. It will show up blocked areas by being a lot cooler at the same height, and should show a temp drop from top to bottom.
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Howdy boys, sorry I didn't get back to you yesterday. OK, here's the full story. The original engine is worn out, so it got pulled and a replacement was put in. The replacement was .125 over on the bore, but we decided to use it. It ran fine for about two months, then began to overheat. I check the radiator and block with a heat gun and the block was anywhere from 200-230. Way too hot. The radiator was around 170-180. My first thought was timing, so I checked it, right on. Then I thought, not enough flow, so we flowed water through the radiator and block. A little rusty, but not bad, and the radiator seemed to flow adequately. Continued to overheat, so we pulled the pump and it seems normal. Since the engine was bored to .125, I thought that might be an issue. Talked to my builder and he was of the same opinion. They do tend to get hot sometimes. So, the young man who owns the car decided to buy another engine and use it. This engine was taken out of a running car. We watched it run on a stand. Put the engine in and same thing, still overheating in the same spots. The timing is correct, there is no thermostat, and it runs fine, so I don't suspect the head gasket is bad. We pulled the hoses and backflushed the radiator and block. Got some crap out, but not a bunch. Put it back together and same thing, still getting hot. So, I sent him home with it and he bought a cleaning kit for the cooling system, which produced more rusty water, but didn't really help the heating problem. He is going to pull the radiator today and I will take it to the shop and get it taken apart so it can be rodded. It has to be the radiator in my opinion. My reasoning is, the first engine we put in the car had sat for several years with no head on it. Who knows what may have been in the block. Mouse nest? I cleaned out a gas tank that had a rat nest in it once. So, the radiator, even though flowing what looked "ok", may be filled with junk. Yeah, I know, I should have checked this before having him do all the other guess work I had him do! Anyway, that's the plan for now, get that radiator cleaned out for sure. Thanks guys, I'll keep you posted. And yes, I feel like a dumb *** for not paying a little more attention to detail here!
