Flathead runs hot - won't cool

My 36 had the same issues and I tried everything you have including Skips pumps, what fixed it was increasing the jet sizes a lot, Flatheads do not like light tan plugs a little black cured my car, it ran stronger and never overheats

Now I've heard that more than once. Ken ct said to use 49 jets in my 94 carb instead of the stock 51's but now I'm running hotter than I used to. I'm going to try going back to the stock 51's and see if that makes a difference.

It did. I put the 51's back in and it lowered my temperature by at least 20 degrees! :) Try it. You'll like it.

Thanks for the tip JonC.
 
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I was fooling around with my 8ba have never timed it with light.
Got the old timing light out and found out few things.
From the mark on pulley I was guessing how much advaned i had with stock dist.I marked 1 inch and another mark at 1 1/2.
At idle put on mark (O)on pulley,then speeded up to guess 2k 2,5k
Full advance went to about 1 1/2 past mark.
My guess thats about 28 degs full advance.
I find it very hard to have a dual carb engine to run lean.
But when adding a pvc sucking fumes and dumping them in carb would cause to run lean.The down draft tube is to exit heat and fumes.
 
You need to change head gaskets. When running olld style heads o 8BA use old style gaskets. Also as Old Henry says, fatten up the carbs and see what happens. You might be supprised.
Butch
 
The brass radiators have a "R" value half of ALUMINUM. One inch tubes are harder to cool than fractional tubes. Get a good brass radiator and no restrictions.
 
Make sure the upper hose's are not collapsing,you said it was ok at idle,moving a lot of water might suck in the hose,maybe drawing a vac on system,ck radiator cap.
 
Are your carburetor jets too small? Running lean equals more heat.

Running lean would have other symptoms besides running hot. There would be backfiring and poor throttle response. A vacuum in the cooling system is probably not going to happen because the pumps can not pump more water than they can suck. Most of these ideas have been presented on the HAMB. The radiator is a poor design and aluminum. Copper radiators cool almost twice the amount of aluminum. One inch radiator tubes and two rolls might work on a quarter mile race car. One inch tubes are harder to cool than a 3/16 tube. If I had a big dollar hot rod like this, I would buy Skips water pumps and a copper radiator from Brass Works or Walker. I would purchase the radiator first. There are a lot of 49-53 flatheads running 39-48 heads without heating problems.

There is no need to run a flathead above 180 degrees.
 
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Running lean would have other symptoms besides running hot. There would be backfiring and poor throttle response. A vacuum in the cooling system is probably not going to happen because the pumps can not pump more water than they can suck. Most of these ideas have been presented on the HAMB. The radiator is a poor design and aluminum. Copper radiators cool almost twice the amount of aluminum. One inch radiator tubes and two rolls might work on a quarter mile race car. One inch tubes are harder to cool than a 3/16 tube. If I had a big dollar hot rod like this, I would buy Skips water pumps and a copper radiator from Brass Works or Walker. I would purchase the radiator first. There are a lot of 49-53 flatheads running 39-48 heads without heating problems.

There is no need to run a flathead above 180 degrees.

After all I've tried this makes the most sense to me. I've always felt that more rows of smaller tube with more surface area can disipate more heat faster the less rows of larger tubes. Also felt copper works better with water than aluminum. Aluminum is good but I think its a cost thing. As far as my water pumps, I must have been mistaken regarding high volume.

I don't think now that they are high volume. They were purchased thru Speedway and have sealed bearings which are better than stock , but I don't think they are High volume.

New SPAL fan arrived today, so thats the next step.
 
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