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The engine in my 54 Clipper (288) pegs the heat gauge in less than 5 minutes. I have flow thru the radiator, but the head seems very hot. The fluid is hot and the radiator and hoses are hot, but not boiling. When I checked the oil it was not hot or even warm. What could be my problem and what would be my next test or step to fix? The thermostat is opening and I removed the upper hose and ran the engine to see if the water pump was working, water squirted out of the hose immediately. HELP!

Dear Willis:

Let's start by getting some good data on your problem.

If the radiator overflow is not pouring on the ground then the motor is not boiling.

A good start is check the uniformity of the warm up. Does the back of the motor get hot much faster than the front?
If it does than you have a distribution problem.

Next, remove the front grille pan and check the efficiency of the radiator. Is the top warm and the bottom cooler, or is the bottom getting warm before the top? There should be a sensible temperature change from top to bottom.

Next, get a meat thermometer or whatever and check the coolant temperature. If it is not getting above 180F then you have a gauge problem given the cylinder head temperature is uniform to the touch.

Finally, get a cheap multimeter from WalMart, Radio Shack, the hardware store, whatever and test the temperature sender. It's at the back of the cylinder head. Disconnect the wire and test the resistance to ground with motor cold. It should have lots of Ohms. As the motor warms up the Ohms should decrease gradually. If they become zero before the motor is hot then the sender is bad.

That's a start and hope this helps.

Thanks a lot Tim, this is exactly what I need to trouble shoot the problem. I think a may check the sender first then follow up on all the list. I should have the results tomorrow.

Thanks
Willis

Disconnect the wire and test the resistance to ground with motor cold. It should have lots of Ohms. As the motor warms up the Ohms should decrease gradually. If they become zero before the motor is hot then the sender is bad.

Just as a bit of added information for anyone else with gauge issues, 51-6 Packard (King Seeley thermal type gauge) senders should be in the range of around 80 ohms max and around 10 ohms minimum +/-. Approx same values as some Ford senders which we've found work but NOT GM. Their senders have approx the same resistance but at the opposite ends. Other Packard years use different gauges with different mechanisms or values. Idiot light oil senders are just switches that transition at a specific range so will check out as either short or open.

For troubleshooting, the temp sender would be around 80 when cold and 10 when boiling (around 220 degrees).
Gas is around 80 empty and 10 full.
Oil is 80 when engine off and around 10 at the top end pressure -- not sure what pressure that is presently -- maybe 100 psi.

Our gauge senders should never go to a direct 0 ohm short. That condition for an extended period can damage the gauges.

Did some testing today and a backflush of the system. The gauge reading is correct. The head got hot almost within a minute. While backflushing the head still got hot. I am thinking I need to pull the distribution tube. When I took the upper hose off the radiator and started the engine the fluid shot out in a stream that is why I thought it may be the radiator and not the water pump. I still think I'm missing something. I will go over Tim's list again and review. All items get hot just like normal except I think the head is too hot and gets there very fast. How hot should the head be while running for 2 to 3 minutes? The head seems equally hot across all eight.

Willis, the list of candidates that can contribute to overheating is long and we've been over it many times before on this site, somewhere I'm sure you'll find a list or lists. Sure it could be the pump, the water distribution tube, retarded ignition timing, collapsed hoses, lean mixture, undersized or otherwise restricted exhaust piping or muffler, and on and on. It could also be and more often is a combination of such things.

I'm not suggesting you not continue with Tim's list, that's a nice analytical approach. But very often one of the major contributing causes is the radiator and since it's so easy to remove on your car, perhaps you might start by just removing it and the flow-rate tested. If the flow rate is within specification, then proceed with the other possibilities and at least you've eliminated the single most common cause or contributor

Gravity flow rates are in the specs; I don't have the 53 specs in front of me at the moment but for a 54 Clipper with the 288 it's given as 36.6 gallons/minute and I doubt 1953 is any different.

Good point, I am going to pull the radiator tommorrow and have it checked. If it is okay I can go right to the water pump and distribution tube. I will also check the timing.

Let me know if your distribution tube is damaged. I have a spare one for a 51-54 288 or 327.

I will be pulling the water pump and tube next week, Thanks for the offer, it's always good to have a backup plan. Hopefully my tube is ok or just needs cleaned up.

One other thing I didn't see listed, you should check is the heat riser. It is the flap in the manifold that closes off the exhaust to warm up the motor. If it is stuck in the closed position, overheating in warm weather can occur in short order.