Overheating issues
 

I’ve got the newly rebuilt flathead back in my 40 and it’s running good . Problem is it’s like the farther you go the hotter it gets. With thermostats or without, block is clean, new radiator, rebuilt water pumps , timing is good. Yesterday I removed the upper radiator hoses and filled the heads with water up to the neck and removed the belt so the pumps wouldn’t turn. Cranked it up and looked for bubbles in the heads, there wasn’t anything there so that eliminates a leaky gasket . Before I got this car it sat in an open shed for the probably the last 20 years. I’m beginning to wonder if the exhaust could be partially blocked by mice or something. I’m at wits end with this thing.

Re: Overheating issues
 

Nice looking car but sideways is is hard.Try a vacuum gauge on it.It will tell you if have a choked muffler.

Re: Overheating issues
 

Ken's '40...
https://www.fordbarn.com/forum/attac...4&d=1652984701

Re: Overheating issues
 

Ken, Are the old radiator hoses soft and collapsing and restricting flow?

Re: Overheating issues
 

No, they are new.

Re: Overheating issues
 

A new engine will tend to run hotter at first. What about carburetion?

Re: Overheating issues
 

Yeah, I was expecting it to run hotter since it is all new . Took it for a 10 mile run yesterday and it was pegging the gauge when I got back home. Checked it with my temp gun and both sides were consistent 210 degrees. Best I remember the carb has .051 jets. It has the 91-99 carburetor on it.

Re: Overheating issues
 

What do you mean " The farther you go the hotter it gets?
How hot does it get? Boil over?

Re: Overheating issues
 

Yes, it will boil. For example, I can drive it 2 miles down the road and back but if I were to go say 10 miles like yesterday it’ll get hot.

Re: Overheating issues
 

How do you know the timing is good? Did you put a degree wheel on it and put markings and a pointer on it?

If it continues to heat up (and the timing is right), then my guess is that either you're not pumping enough water through it, or your overall cooling capacity isn't good enough.

What type of radiator did you put in it? Also, are the water pumps ones with modern impellers (like Skip puts on them) . . . or stock type impellers?

Re: Overheating issues
 

No, I did not put a degree wheel on it. The camshaft is an nos Ford cam so I figured it would be good. Distributor and ignition timing was setup on my Sun distributor machine. The radiator is one of the new Bob Drake units. Pumps are stock pumps.

Re: Overheating issues
 

Is the radiator clean on the inside and can you see the water circulating in the radiator?

Disconnect the lower hoses and flush out the radiator with a hose to check the flow.

Re: Overheating issues
 

I’ve eliminated the exhaust possibility . I had an nos muffler I wanted to install anyway. I’m thinking I’ll take the radiator out of my coupe and put it in there and see how that goes. New ain’t always better. ��

Re: Overheating issues
 

Good plan. If it keeps getting hotter the further you drive, it sure sounds like radiator. 210 and steady isn't dangerous but rising from there and losing coolant/boiling is another matter. The radiator swap may be the answer.


Terry

Re: Overheating issues
 

RE Pumps: I always run Skips pumps on my engines - as I like the way he rebuilds them (bearings, not bushings) and his impeller moves a LOT more water than the small straight impellers on original pumps. The engine in my 32 is 284 cubes and I can be stuck in traffic in 90+ degree weather (stop n go stuff) - and it won't overheat. At the Columbus Goodguy's one year I was sitting idling for about 45 minutes . . . and it passed the test with no problems (and that is with a non-pressurized system).

Re: Overheating issues
 

I have a pair of Skips pumps on the shelf. I’ll give them a try. I’m starting to question the repop Drake radiator. I’m thinking I’ll take the radiator out of my 40 coupe and put it in there to see how it goes.

Re: Overheating issues
 

What is the condition of the block innards? Was the block thoroughly cleaned out of crud?

Re: Overheating issues
 

Yes, shake and bake then several hours with a long pointed rod poking around in the water jackets. This block wasn’t bad at all. It was pretty clean to begin with.

Re: Overheating issues
 

Have you checked your gauges. Ya stupid question.

Re: Overheating issues
 

Handy tool you can get almost everywhere.


https://www.amazon.com/Etekcity-Lase...00837ZGRY?th=1