Packard Forum Index » V-8 (1955-56)

The ruff running u experienced is most likely due to the gasoline getting hot and trying to vapour lock or perculate but just border line enuf to allow for continued running. This happens to me here in TN. on occasion during the very hot summers but not often enuf for me take any major effort action. In fact i have a NEW (as in BRAND NEW, not rebuilt NOT recored or anything like that) and will occasionaly experience a stumble or some ruff running under high heat conditions. I also have a large SunPro engine temp gauge to monitor.

The fact that the radiator in your car is not puking out any coolant pretty much rules out overheating or at least rules out any overheating that would be considered detrimental. CHECK THE PRESSURE rating of the radiator cap.

The pusher fan mite help. MAYBE. I ran a pusher fan for a couple of years with absolutely NO evidence of running cooler or better or anything else positive. The pusher fan i used was some junk yard find and i have no idea what car it came from. It was large too.

THe problem is that the pusher fan will tend to block (somewhat) the air flow thru the radiator AT HIGHER SPEEDS thus causing some higher engine temp.

The pusher fan is something that the hot rodders use because of cobbled up engine compartments that do not readily allow for an easy mount of an engine driven fan. In somecases the hot rodders do not want to rob the engine of any power to drive the fan so they use an electric fan.

Since it is BY DEFINITION a HOT ROD ergo they tend to run such high performance engines at rather high temperatures anyway.

Also note that installing a pusher fane on the 55-56 Packards presents a problem. THere is a CROSS BRACE on the horse collar that does not allow the pusher to fit up CLOSE to the radiator thus greatly reducing the pusher fans affectivelness. U can always cut the cross brace away but I sure as hell won't cut the brace.

If u want to put some effort into something that will WORK then come up with a FAN SHROUD for the existing Packard fan and a 6 blade fan.

I have a 6 blade on mine that i bought at a discount chain but it required some machining to the hub (that came with the fan) to mount to the Packard pump.

The pusher fan is just a Q&D hot rod application. Something for waiting at the line up to run the 1/4 mile drag strip with.

As Keith said, if it is not puking out coolant, then it is probably fine.

But if you are still worried, then put a temporary mechanical temp gauge on it as Keith suggested. Put a new radiator cap on it rated at least at 14PSI. Any temp below 220F is fine.

Last year my restored 79 TA got caught in traffic in 114F crawling over Hoover Dam and the temp gauge hit 255F. It survived just fine although it would ping under load due to today's lousy gas until the temp cooled back down to 220F.

As far as the rough running is concerned, I agree with Keith that it is probably marginal vapor lock. I have an aux electric fuel pump on my 55 Pat and 79 TA and I don't experience vapor lock anymore even at crawling speed at 110F.

Craig

this sounds terrible and tacky, but put the mr gasket radiator cap in with the temp gauge built in. Since the water from the motor is returning right under the cap, it's a great spot (on my bathtub anyway).

I put that on mine after rebuild because i knew the factory gauge would be off, and started checking with the infrared thermometer and it reads almost exactly the same temp as the soft plugs on the side of the block and the pipe i used to adapt my temp sender. It's a fairly accurate snapshot of how hot the motor is running, although it costs about $25. You can always switch back to your standard cap once you know your car is doing fine. I think it's a 14psi cap.

"The pusher fan is something that the hot rodders use because of cobbled up engine compartments that do not readily allow for an easy mount of an engine driven fan. In somecases the hot rodders do not want to rob the engine of any power to drive the fan so they use an electric fan."


And, might i add as a hot rodder myself, they want what looks cool or high tech, regardless of whether or not it works better or worse. Or, they just don't know any better.

The best cooling is still a large 5-7 bladed AC car clutch or direct fan with a nice correct shroud and no fan in the front of the radiator to interfere with air flow.

"but put the mr gasket radiator cap in with the temp gauge built in. "

That's the best idea so far. Thanks for the suggestion and the price isn't bad either. I never knew there was such a cap available.

Does it stand any higher than the oem cap????? I have hood clearence issues with my radiator.

Not a bad idea. It appears they only have the one standard length large model though. If so, pre 55 cars with the long fill neck would be out of luck and those seem to be most of the cars with heat problems a second bit of info would benefit.

jegs.com/i/Mr.%20Gasket/720/2470B/10002/-1?CT=999

I am inclined to think that we could create a TV show somewhat like the medical one where someone comes in with bizarre symptoms and they eventually tell them that they have a disease that affects 32 people worldwide each year.....

The twists in the diagnosis and prognosis are fascinating. At this point, I am inclined towards a fan that moves more air, provided that it isn't platinum coated. Seems like it could help a bet and not be wildly difficult to deal with. Coupled with another clean out and new radiator hoses.....

Jack liked something called FLAP. Some years ago I worked for PEAK who had a nice organic flush called Peak Purge which was fabulous at rust removal and neither acidic or base,,,,if it still exists.....

If you removed the radiator hoses would that lead to better flushing?

Any other tips on getting the most effective rust and crud removal?

The cap is a standard radiator cap with a probe that sticks down in a little more than usual. If someone has a long neck radiator of some kind, i'd guess it would still work, but would read low 10-30 degrees max (like my factory gauge)

Cheap way to get a ballpark idea of what your car is up to.

Any other tips on getting the most effective rust and crud removal

If you don't want to remove the radiator for a boil-out, there's always the old traditional method. First use a flush containing oxalic acid, then the neutralizer (carbonate). Then do a back-flush using a flushing gun that fits into the radiator hose and uses a combination of water pressure and compressed air. Disconnect both radiator hoses; do the radiator, flushing from bottom to top with the upper hose removed so the crap doesn't just go into the block. Then flush the block, also in reverse flow. When doing the block you might consider blocking the flow to the heater core, they can become pretty fragile with age.

The flushing guns used to be pretty common fare at flea markets though I haven't seen one lately. I'll post a picture of a typical one later for those not familiar with them.