1952 flat six overheating

wwdaze · Veteran Member

1952 flat six overheating

Fitz · Guru

At first, is the radiator leaking by the overflow of the upper tank tube when overheating?

Is overheating on road use condition or in a parade condition?

Use a infra-red thermometer, and look the temp near the sensor, you must look at a normal temperature around 200-210 F at the rear of the engine.

If you six never been opened be sure that the block is clogged from the low #4 cyl to the high #6. It change everything to clean up the block, not easy under the hood tought.

Fitz.

wwdaze · Veteran Member

Hi fitz;
The rad. is not leaking at the overflow and I am overheating on road use. Seems like idle is not a problem.
Bill

Fitz · Guru

Is the overheat information come from the temp gauge of the car or from the engine running state?

If the information come from the temp gauge, a infra-red temperature gauge will tell the truth by testing near the sensor unit.

Now if it's the engine the problem come from, a timing problem "can" be the cause. But it must take a lot of bad timing to cause overheating on those engine.

You have to put back your thermostat, it's normal to see overheating without thermostat in a engine, but check it before put it in the engine with hot water and outside thermostat.

You may have a exhaust problem, if the muffler baffle colapse inside the muffler you will have a overtheating problem if the exhaust flow is restricted.

But like said before, if the engine as never been opened it surely clogged inside.

Does the overheating problem appear suddenly ?

Fitz.

Canadian Poncho · A Poncho Legend!

Have you checked for blockage in the cooling jackets of the engine? A lot of flat 6's (all makes) were bad for this.

Laurentian · Addicted!

Taking out the thermostat will not help anything as it could make it even worse by not letting the coolant stay in the rad to cool before replacing the hot coolant in the engine. Cars in the southern states still need a thermostat to operate properly. I agree with checking the coolant galleries for blockage and possible repair with an engine flush but check the thermostat in boiling water and a thermometer to see if it operating correctly. My buddy went throuigh three new ones on his 55 fargo flathead before finding out the hard way (engine overheating) new parts can be faulty.

Turdmagnet · Veteran Member

Another thought.

When I got my 51, the previous owner told me it always overheated. He remove the thermostat as well - was in the glove box. I check the thermostat on the bench in boiling water and everything seemed to work properly, installed it, but the engine would still get hot when driving. But what I did find was the front baffle that directs air into the rad was missing. I found it in the boxes of junk he gave me with the car, cleaned it up and got it installed, and the overheating problem went away. My guess is that proper air flow thru the rad is important for these cars as well.

Just something else to consider !!
Steve

Fitz · Guru

Turdmagnet wrote:

Another thought.

When I got my 51, the previous owner told me it always overheated. He remove the thermostat as well - was in the glove box. I check the thermostat on the bench in boiling water and everything seemed to work properly, installed it, but the engine would still get hot when driving. But what I did find was the front baffle that directs air into the rad was missing. I found it in the boxes of junk he gave me with the car, cleaned it up and got it installed, and the overheating problem went away. My guess is that proper air flow thru the rad is important for these cars as well.

Just something else to consider !!
Steve

Yes you are right, this baffle force air to go in the upper part of the rad, but wwdaze did not come back about my question, this situation was appearing suddenly or not?

Fitz.

wwdaze · Veteran Member

Hey Fitz:

Sorry for the delay in getting back to you but I am getting the car ready for a local show that is close enough that I can make it without any major overheating., Just a couple of miles away. . In answer to your question, Yes the overheating just suddenly occured one day. Where exactly does the front baffle attach? I am going to hit the engine and hoses with a heat gun tonight to see if I can find a hot or cool spot. Keep all the answers coming. Thanks a lot for all the help from everyone.
Bill

wwdaze · Veteran Member

Hey everyone:

well I have water flow through the thermostat but quick overheating under pressure. As soon as I drop down to 20 mph the temp drops right down to 170..... I guess the next step is to blow out the block. I used a temp laser and the radiator is regular temp. Any suggestions before I stare tearing things apart???/

427carl · A Poncho Legend!

It has normal temperature with temp gun!
It runs cool below 20 mph...

so as it speeds up, it get more air through the rad, and the waterpump flows more!!

and yet the car overheats confuse

hmmm what do you think guys?

Canadian Poncho · A Poncho Legend!

Maybe a bad water pump? I've seen where the impeller backs out a bit from the housing causing a reduction in flow at higher speeds.

Fitz · Guru

69Laurentian wrote:

Maybe a bad water pump? I've seen where the impeller backs out a bit from the housing causing a reduction in flow at higher speeds.

I agree with you, since the problem occur suddenly. The pump (or belt tension) should be looked before looking inside the block.

Fitz.

wwdaze · Veteran Member

Hello:

I have installed a bran new waterpump and thermostat. I have water movement in the radiator. I have NOT used a thermometer on the radiator water yet but I am going to check out the wiring on the heat sensor and check the temp gauge. If all checks out I will figure the block has a blockage. Thanks for the input.
Bill

Fitz · Guru

Good luck and let us know.

Fitz.