Packard Forum Index » Post-War (1946-54)

The 49 runs hot on the gauge within a couple of miles and after 10 is overheating. Block and rad have been flushed cleaned, scoured etc. no indication that water pump is malfunctioning. Timing is where it's supposed to be. I'm at wits end. Does anyone make an aluminum rad for 49s? I've found them for 39s. Do I take out the thermo? Head gasket has been replaced, head decked. 3 speed od.

The large majority of overheating problems originate with the gradual deterioration of the radiator and that's the place to start, have it checked for gravity flow rate and while it's off, pull and clean the water distribution tube if you haven't already. Then check the impeller and impeller clearance on the water pump - impeller clearance is critical to pump efficiency.

Removal of the thermostat will not be helpful and more likely will be harmful. However it wouldn't hurt to remove it and check it (in a pan of water on the stove with a thermometer) or just replace it. Have you checked the lower radiator hose to insure it is not collapsing under suction or restricted internally?

PS- one occasionally sees overheating caused by an incorrect (too narrow) fan belt. A proper width belt when tensioned will ride on the sides of the pulleys, not the base or floor. Worth a check.

The radiator place checked it and said it was more than enough to cool it. Before I pull the rad again I'll replace the lower hose. I checked the block with the heat gun and the rear of it on the manifold side is no hotter than anywhere else, so the dist tube should be fine.

Do you recall what the actual radiator flow rate was?

Can you see water circulating through the radiator after the thermostat opens up?

The system can't be circulating much water if it overheats that fast.

Good Evening all...Our 49 ran hot when we purchased her and we cleaned out the cooling system, rebuilt the water pump, added a new radiator and while we made progress the final part of the puzzle was a slow acting heat valve and a vacuum advance that did not work. We also changed to a rebuilt Delco Distributor from an Autolight that was pretty well warn out...perhaps some additional things to check. Ernie in Arizona

Have experienced overheating problems with my 1954 Clipper Deluxe(see photo on National Rally in Australia)Solved the problem by installing a shroud around the fan and a six bladed fan from a mid seventies Ford. Now the problem is getting it up to operating temp. on a cold day.
Hope this helps. Regards Pepepackard.

Did you need to modify the fan from the Ford to fit the hub on the Packard or was there something else such as a spacer or adapter used? Does it have the typical thick fixed pitch blades and if so, how is the overall appearance compared to the stock fan?

Several have asked about finding Packard heavy duty fans or six blade fans in general when adding AC and so far none found seem to be a relatively easy bolt on other than the very thin blade universal flex fans. Those look so out of place many don't want to use them. Any info you could provide such as year, model or extra parts needed to mount the Ford fan might be of benefit to anyone looking.

I had "no indication that water pump is malfunctioning." on my 56 when the impeller lost its grip on the shaft. Everything was smooth and quiet and then it overheated. Make sure water is actually being pumped.

Are you 100% sure it's actually overheating (blowing water out the overflow), etc? Could be a faulty gauge or sender giving you a bad reading?

Those handheld IR Thermometers are great to see what is going on. Also, check the temp from and back along the head to see if you may have a clogged water distribution tube.