Packard Forum Index » General

The VERY first thing i would make sure of (i'm sure it was mentioned) is that you have the long reach radiator cap. If you do not, this project is doomed to fail as it takes very little for it to start dumping out.

A temp gauge on the head itself (or IR laser one, whatever) would be a quick indicator how hot the metal of the head is when it's boiling. If it's a fairly low temp, i'd start looking at that cap.

I made the same mistake, the short reach cap is very close looking and fits ok on the radiator neck even when it shouldn't be used. Mine would overflow driving in about 10 min if that with the wrong cap.

I had similar issues on my '48. I went through the entire cooling system, but neglected to replace the radiator cap, because I thought it looked okay.

The car would get hotter as I drove it, eventually spewing water out the overflow. Bought a new Stant 10206 cap from NAPA, and all is fine now.

Keep in mind I had the right cap- only mine was worn out. It was evident when I compared it to the new one as the rubber on the bottom was missing! Your situation could be more severe if you have a cap that is too short.

Put a thermometer in the radiator neck and watch it. I still think you have a flakey gauge or sender.

Also remember if you overfill the radiator, that water has to go somewhere when it expands from normal heating. So the boiling over may just be that extra water getting expelled. Verify you have the correct radiator cap as well.

Got a new Stant long cap today and I will take some of the water out of the radiator. Definitely will use a gauge to check what the temp is at the radiator and on the head. Lots of very good trouble shooting suggestions from experience Packard enthusiasts. You cannot get that many ideas in month without this forum. Thanks to everyone I will keep posting until the car is COOL !

Quote:Packards are always

I've been having trouble with my 51 overheating for some time. Found two problems - first is the water pump. Sent it off to Gould for rebuilding. Someone in the past put a Chrysler impeller in it, which impaired the performance. Second, the dummy who replaced the thermostat (me!) put it in upside down, with the spring side facing up, instead of down towards the block. I should be getting the pump back shortly, so I will let you know how the car runs then. Hopefully these two fixes will make a big difference.

Put everything back together, got a new NAPA TS6464 temperature sender and hooked it up. Started the car and the gauge went to HOT before the engine was running 10 seconds( bad gauge or wrong gauge or what?) Ran the car with a meat thermometer in the radiator for 15 minutes and never went past 180 degrees, shut it off and the temp went up past the max on the meat thermometer over 185 ++. Started the car up and the meat thermometer went down to about 180- in a minute. So it looks like the problem I have is in the probe. The probe I took out had no teflon tape on the threads, I taped the one I installed. Am I preventing the probe from having a ground? I guess I can look into replacing the idiot light with a gauge to be sure of how the engine is doing. I already have a oil pressure gauge under the hood. I am getting the retired NAPA employee discount now which really helps on getting the parts! I worked for the local NAPA for a few years.

You need to make sure you have the right sender (ohm range) to match with the Packard gauge or it will never read right. Remind me again, do you have a '54 Super or a Deluxe?

If you have a Deluxe, I have a couple of spare Temp gauges for them, but not any spare senders. So if you get the correct sender and it still reads bad, and the wiring is good, and all the test point to a bad gauge, let me know and I will see what i can do for you,

I had been looking at that same TS 6464 temp sender and noticed something on the Napa website which brought up a question. That same number is used on three applications which doesn't seem possible. On the applications for cooling fan and temp light they show these specs:

Temp Sender Switch Temp Rating : C At 100 Deg F w/ 23% Tol, O At 220 Deg F 13.5 Ohms w/ 9% Tol

On the same part number for gauge operation specs are:

Temp Sender Switch Temp Rating : 11.5-13.5 Ohms Resistance At 220 Deg F

I'm kind of having a hard time figuring out how the same sender can work 3 different items with completely different needs. One could assume the C and O on the first spec would be closed and open but unless there are strangely configured relays involved, doesn't seem plausible for both fan & light operation. To have a resistance range mixed in to what would seem to need a simple on/off function seems odd as well.

Out of curiosity, could you measure that sender. At cold, we would need 80-100 ohms minimum. More would probably be OK as long as ohms start falling fairly quickly once engine started to heat. At 180, we would probably want in the 25-35 range and at boiling or 220 the listed spec of around 10.

I have a Special 288. I will check resistance to see if it is the correct one.