Continuing engine problem

On radiators. Sometimes a radiator can perform exactly as new and still overheat. The reason for this is, the tubes are soldered to the fins for heat transfer. On a radiator that is 80/85 years old, this solder joint can be compromised and broken loose. The result is an invisible problem for heat dissipation and overheating. A new radiator should solve this problem since I know of no way to re-solder the fins and tubes.

FWIW.
 
"Too tight" has always caused two (2) types of many past Model A mechanical failures"

"Too tight" to pay for qualified professional engine re-building services is usually the most common one."

This is exactly right, HL
I can't imagine getting an engine from a rebuilder that told me it's going to be real tight, until it's broken in. Rediculous.
 
Didn't the factory set up the bearings somewhat close and then run them in on a jig powered by an electric motor until freed up?
 
If I may.. there was a post awhile back that eventually centered on pistons, made overseas that many of the vendors were selling. There were many failures. Modern engine re-builders buy parts from manufacturers who specialize in what they do. Most of them have dropped model A pistons because the market quantity isn't there. Now we have products made by shops overseas filling a void that they know very little about. So, who now makes pistons that work well for our old fords? Look closely at the skirts, both inside and out for a company's name. I suspect that there won't be any. This may be the key to your problem, and that does not, in any way imply that you don't also need a radiator.
 
Ray, in your opening statement, you say it overheats , THEN seizes. It sounds like the problem is overheating. How hot, and then why?
 
Re: UPDATE 7/13/17: Continuing engine problem

700rpm said:
TODAY'S UPDATE: I took the block and pistons into Portland Engine Rebuilders today and told them they needed to hone to .0045. I explained that it all seems to have come down to the issue of the sleeves not transferring heat like a simple bore of the block, combined with the already questionable water distribution in the block. They posited the idea that the overheating may never be solved because of the sleeves. I've sleeved one other engine back to standard, and the builder claims he set the piston clearance at .003. That engine has never locked up, broke in like normal, and runs great.

At this point I am out of options. I'm going with the .0045, new rings, clean block, and new radiator, and if that doesn't solve this, I'm done.

ORIGINAL POST: I posted this over on the VFF, but some guys here don't read that forum, so I put this to the Barn:

This engine, with only 4000 miles on it since rebuild, has always overheated and locked up when shut down after overheating, which is usually when driven at 45 or less for 30 minutes or more. (This did not and does not happen when driven under 35 and/or just around town for less than 45 minutes). I thought I had this problem fixed. But apparently not.

Here is the history: On 3/16/14 I installed an engine which had been boiled out, sleeved back to standard, new pistons and rings from Snyder's, new valves, exhaust valve seats, new lifters, and new babbit by Bill Barlow. It was tight, but I figured it would loosen up during breakin, which I did very carefully, as I have done with all my previous engines.

After 2000 miles it was still overheating and locking up on shutdown. I took it apart to check measurements. Ring gap, rod bearings, and piston clearance were just where they should be, according tbirdtbird, Bill Barlow, Tom Godish, and several other commenters on the Barn. But when reassembled it had the same troubles.



Thanks for indulging my long post.
Click to expand...

There are 2 key statements,... "locked up when shut down after overheating"
...........................It didn't lock-up when it got hot!, RUNNING!................
When you shut the engine down the temperature of the engine / water get
HOTTER.
Not unless Ray wrote those 2 statements backwards..?

 
Dudley, those two statements are correct. It's part of the mystery. But all will be revealed. Or not. :rolleyes:
 
I've seen this a few times, many years ago. The machine shop gurus said the reason it doesn't seize up when running is because the engine has enough power to overcome the tightness, but once stopped the pistons and the block glom together and then it's almost impossible to turn over until it cools down.
 
700rpm said:
I don't think so. The Model A is not a pressurized system, it's a splash system.
Click to expand...

Yes, agreed, splash system, but I thought the pistons looked like lube deficient. Are you sure the splash pan is in the correct position and it does not have any extra holes in it?

What type oil are you running?

John
 
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