New Rebuild Overheating
 

Finally got the 59A started. The high idle problem was the throttle levers were sticking a bit. Got the timing and dwell set correctly. BUT the engine over heats quickly to over 240 degrees on both sides with electric fan running. I`ll list what has been done so far in the cooling. 1. 50/50 mix with the proper amount of Water Wetter. 2. Have an electric fan. 3. Went from a 16lb radiator cap to a 7lb cap(no change). 4. Running 180 degree thermostats. 5. Aluminum radiator(32`style). The block was tanked at the machine shop. Heads planed. What am i missing here? Get this overheating problem fixed and i will be good to go.

Re: New Rebuild Overheating
 

Tanking a block does not insure it is cleaned out inside the water jackets. However, your cooling issue seems like a bigger issue than that. Are you sure the radiator has a large enough capacity for the engine?

Re: New Rebuild Overheating
 

Are there holes in the thermostats to allow the air to escape?

Re: New Rebuild Overheating
 

Also, are you sure you have the timing is correct?

Re: New Rebuild Overheating
 

Correct on hot tanking.
Scraping, prodding, poking at all the crud is the first.
Then bake blasting
Then more scraping, prodding, and poking to get any left over bits.
Tanking is the final cleaning step.

Re: New Rebuild Overheating
 

Under what circumstances is the engine overheating. At idle in the garage? Driving.

Confirm that thermostats are working and you can see full flow into the top tank, looking through the radiator cap opening. Does the fan have a shroud. If not, they can be ineffective.

If the new rebuild was put together a little tight, the engine has to work pretty hard, especially at idle. You need to get that break-in under some load, like accelerating and decelerating at highway speeds.

Re: New Rebuild Overheating
 

I had the 327 in my Corvette rebuilt a while ago. When I got it running, it ran well, but would not idle for any period of time at all before it started to boil. I tried everything; changed the radiator cap, flushed the system, and a bunch of other things. I was just getting ready to pull it, when all of a sudden it settled down. Like the previous poster, I believe that it was built too "tight", and after it finally got broken in, it was (and still is) fine.

I'm not saying that this is your problem (flatheads have more cooling foibles than SBC's), but this is what I experienced.

Re: New Rebuild Overheating
 

Especially if it was rebuilt with 4 ring pistons. That extra ring has a lot of drag.

Re: New Rebuild Overheating
 

Interesting. Maybe OP should run it hard to see if it cools down?

Re: New Rebuild Overheating
 

I had the same problem with the 49 7years ago after losing half the summer I changed the intake end of problem . Jack.

Re: New Rebuild Overheating
 

Who did the machine work and who assembled the engine?

Re: New Rebuild Overheating
 

How did you set the timing? A stock 59 engine has no timing marks. I have a 59 in my pickup. I had to use a vacuum gauge to set the timing because I have a Mallory electronic distributer. I had over heating issues due to late timing before I timed it with the vacuum gauge.

Re: New Rebuild Overheating
 

The radiator is of the stock size as an original 32` would have. There are holes in the thermostats(thinking of taking them altogether. I am positive on the timing(2 degrees btdc). 30 degrees dwell. Its at idle in the garage with the electric fan running and i even put a portable fan in front of the radiator(no fan shroud). I am running 2 Stromburg 97`s on an offenhauser aluminum intake. I would rather not say who did the rebuild because that person is has a serious illness thats not curable, but is well known here on the Ford Barn.

Re: New Rebuild Overheating
 

I guess a question would be, why are you idling the engine in the garage, that is just a recipe for over heating. Especially on a new rebuild. If it were mine, I would determine if it is actually overheating before I attempted to fix a problem that might not exist. Is there a reason it can't be driven? If there is a reason to believe the thermostats are not opening, taking them out might be a good idea, that at least eliminates that issue.

Re: New Rebuild Overheating
 

The person who rebuilt the engine had set the TDC mark on the pulley in alignment with the pin on the distributor cover. I have Skips rebuilt water pumps. I was just reading an older FB post and it was mentioned that they push almost twice the volume of water!!! It would seam that the water would not have an adequate time to cool down as it passed through the radiator and fan? Idling in the garage to set timing and adjust dwell. We did not just let it just idle for the fun of it. Run for 2 to 3 minutes, make an adjustment then shut it down as it down. The distributor is a Bubba Chevy conversion.

Re: New Rebuild Overheating
 

P.S. The distributor has only mechanical advance, no vacuum on dist.

Re: New Rebuild Overheating
 

Take it out and drive it, if possible. JMO
Paul in CT

Re: New Rebuild Overheating
 

Have you tried it without the thermostats - just to be sure there is good coolant flow.
Did you check timing with a vac gauge as mentioned? Otherwise take it out and drive it.
If you're loosing coolant, bring along a gallon.
Did you check temp with an infrared gun? Top and bottom of radiator? At the head / radiator hose ? Do you have air in the system?

Re: New Rebuild Overheating
 

Heat rejection is a function of flow rate. Faster the flow within reason, the more heat rejected. Too fast is an old wive's tale that refuses to die.

Re: New Rebuild Overheating
 

If it is overheating in 2 or 3 minutes that does sound like a serious issue! I feel your pain. But something that severe should be something that can be determined. I vote for pulling the thermostats and checking the water flow in the top of the radiator.