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Sorry about being away so long. I put the Packard into storage and had some family issues that needed to be attended to.
Well I have something tangible this time around.
I put a SW temp gage on the engine and replaced the 180 deg
with a 160 deg thermostat.

Well now the engine warms up to 160deg seems to hang there then starts climbing. Driving around the neighborhood it runs between 190-200 swinging depending on speed.

When I stop the temp continues climbing up to 230deg. Didn't let it go any further. It wasn't showing any indication that it was going to stop any time soon.

What is the "normal" operating temp for a 288 ?
What temp is too high ? 210? 240? 280?

My original gage spiked at around 215 so it may have been
220 or so when I shut it down. Verified this with a UV temp gage.


Again.. sorry for the delay. Really appreciated your feedback and comments.

Thanks
OTG

Thermostat doesn't make any different to the upper temp of the engine (assuming it's not stuck). The thermostat temp is just the rated temp before the thermostat opens fully. The thermostats purpose is the help bring the engine up to normal operating temp. It has no function in the actual cooling itself.

I would take a look at your radiator and water pump.

Also have you checked your ignition timing to make sure it correct. If its off that can cause an engine to run hotter than normal.

An engine's lower running temperature is determined by the theromostat, as Kev says. If you have a 160 thermostat, water flow thru the radiator only occurs after the t-stat opens and assuming everything else is up to snuff, the engine running temperature should remain at about the same temperature, a bit higher perhaps on long, hard climbs or sitting in traffic on a 100 degree day.

If your temperature readings are correct, you've got a cooling system problem and perhaps someone will lead you to a long list of things to check out which has been published here before.

Some of the primary culprits are too-narrow a fan belt bottoming in the pulley groove (this one is often overlooked); retarded ignition timing, restricted radiator tubes and/or bent fins on the tubes, too much water pump impellor clearance, undersize exhaust system or overly restrictive muffler, blocked or restricted water distribution tube, collapsing lower radiator hose, build-up of hard water salts on the internal water jacket surfaces, and more.

Correct timing on a 288 is important. I drove our 49 from Illinois to Niagra Falls trouble free. the second day our car started overheating. Went to radiator shop and had the cooling system flushed, radiator tested and new cap installed. I checked exhaust flow and heat riser and they were ok. I was ready to pull the head and replace the head gasket when a old timer came by and asked what kind of problem I had. I told him and he asked me to start the engine, then he asked for a screwdriver and he set the timing by ear and my overheating problem was solved.
Good luck in solving your problem.

After reading all of the posts again. I decided to go back to the ole "in god we trust everything else we check".
Well I started the car with the hood off. (heavier than it looks). There is absolutely no water circulation up to 175 deg. It has a 160 thermostat in it now. I purchased this thermostat from PEP boys and was wondering if the "Packard" Thermostat is different than this one ? Just checking.
They are both the same dimensions /different temps. I still have the 180deg that a shop put in. Next I was going to remove the thermostat and see what the flow looks like. There shouldn't be anything else in the way (restricting flow )right?
One other thing .. the spring on the thermostat goes towards the block .. right ? Sounding paranoid yet? Isn't there a metal tube (about 2in dia)in the block around the thermostat ? or am I thinking about another engine ? Don't remember seeing it when I changed the thermostat yesterday.

Thanks again
Kevin

There should be either a wire spring retainer, or a "metal tube" that acts as a spacer to keep the thermostat in place.

Spring (or bellows) side towards the engine. Also it is possible to get a bad thermostat from the store. Put the thermostat in a pan of water heat it on the stove until it opens. Then you can check the temp with a thermometer.

Thanks for the sanity check. I have a spring holding the thermostat in position. Could have sworn that I had a tube in there at one point. So much for old brain cells.
I'll check the thermostat as you suggested. Wonder how the temperature will go without a thermostat.

Thanks
Kevin

Once your problems are solved, running w/o a thermostat is not recommended, engines are more efficient and give better longevity when running at normal temperatures. W/o a thermostat you should see turbulence immediately in the top radiator tank, and it's running temperature may or may not be lower, depending on the condition of the balance of the cooling system. Have you looked inside the cap at the top of the core for corrosion building up and restricting the tubes?

Remember, the higher the differential between the ambient temperature and the coolant temperature, the more efficient the heat exchange.

I checked the radiator and removed the plug on the side of the block. This engine is as clean as new. No corrosion in the radiator either. whoever restored this car did a real good job that is for sure. This is why I am so surprised that there is a cooling issue in the first place.


Agreed. It will have a thermostat when the test is completed. I assume the over-the-counter thermostat and the real genuine "Packard" thermostat are one and the same. Except for the $15 markup for the Packard one of course.

K

Well now I am really confused. I removed the thermostat and the radiator cap. Started the engine. There is virtually no coolant flow in idle, an occasional wirl pool about the size of a dime but no real flow. The water heats up rises and runs out the overflow. I revd the engine and then there would be significant flow and water turbulence at about half throttle. No wonder it overheats in idle. Another interesting thing. I ran a hose into the radiator when it was running to see if anything nasty came out. Nothing to mention except the radiator held the water in the fins until I revd the engine again. Doubt my hair will freeze any time soon. There is very little airflow thru the radiator in idle also. Can someone check and see if any of this is "normal". If the water pump wasn't just rebuilt I would say that it isn't working correctly. BTW the engine did manage to get to 190deg and the temp diff was 10degrees
between the bottom and top. Does this radiator flow from top to bottom ? Did you know if you shine a uv temp gage thru the fan it will read low. JJ

Any ideas ?
Thanks
Kevin