Packard Forum Index » V-8 (1955-56)

I am considering the purchase of a 1955 Packard 400 hardtop. I've been told several things about the 1955 V8 engines and their oiling problems. I'm wondering what is true.

One story is that the '55 engines all had inadequate oil pumps. Don't buy a '55.

Another is that Packard engineers found and fixed the problem sometime during the 1955 model run. Buy a '55 only if it's a late '55.

Another is that Packard engineers found and fixed the problem for the 1956 model run, so if I buy a '55 I should change over to a '56 oil pump. Better to look for a '56.

Another story is that all Packard V8s had inadequate oil pumps and the only fix is to substitute a GM oil pump.

I would surely like to get the straight of this situation before I plunge and buy this '55. Can anybody get me straightened out?

Thanks,

Steve

I think you will probably get many opinions but it is true early 55s had oiling issues -- not so much due to the pump but to "leakage" from other places. The lifters were changed to a different type, rocker shafts were revised to cut down on too much oil being applied to the rocker arms, the cam thrust plate was revised to eliminate a steady stream to the timing chain into an intermittent spurt. All this was done early in the 55 production and sent to the field to be done so if the car was serviced those causes should not be an ongoing issue.

The oil pump has been a continuing guess as to what exactly was the problem. Packard issued a couple of fixes because they thought air was being drawn in thru the pressure relief valve and I believe they also increased the capacity sometime in 56. There is a different casting but I am not totally sure anyone knows exactly what the changes were.. Others have thought that the problem was due to pressure swelling the potmetal plate joining the vacuum pump so they revised the pump with a "fix" to use a heavy metal bottom plate and eliminated the vacuum portion. Others have felt the problem lies in the fact there is no upper bearing or bushing. Misalignment or lack of support for the shaft allowed wear in the cast iron which again allowed air to enter the oil stream. There was another "fix" devised to add a bushing and shaft support for the upper shaft.

The funny thing is the problem is not universal. Some still have their original pumps happily supplying all the pressure needed and other pumps after a short time started allowing air into the system so the lifters start clattering. The Olds pump has a higher capacity and seems to have solved the problem no matter what the original cause but you do give up the aux vacuum pump for the wiper motor. That is easily accommodated by reverting to the dual action fuel pump used in earlier years.

Steve, others far more informed than me will provide info but there is no simple analysis that explains everything and that everyone would agree with. Yes, the V8 had a series of running revisions to the oiling system, several to the pump, the lifters, rocker shafts, cam thrust plate, and probably more.

Many V8 Packards of both years have oiling problems despite the changes, in fact far too many. Yet others like mine, approaching 100,000 miles, has never had an issue.

HH56 Quote:

As one of the co-inventors of the Olds oil pump adapter kit (now sold by Jack Vines), in my (not so humble) opinion, the Olds pump completely solves any issues with Packard pumps, reworked or not, new or not. It there are clacking lifters and/or or low oil pressure at idle, then you need an Olds pump and adapter kit PERIOD.

Of course, if you don't currently have an oil pressure problem on your 55 or 56 (both are susceptible), then don't fix what ain't broke.

Also, one can substitute an electric wiper motor as well or use the alternate vacuum source fuel pump with the original motor as described in the quote above.

Craig

Was told AMC redesigned the oil pumps in the engines that Packard sold them, and that took care of the problem. Not with my 1956 352. Besides noisy lifters, my engine failed pre-maturity with the main bearings failing. Had the engine rebuilt with the PI oil pump, with no problems.

The PI pump is the heavy bottom plate and I have one in my car too. For a lot of years that was the only option that seemed to get any press. Think it was devised by Harold Gibson of PI but longtime PI members would have to confirm. I think it was Bob Aller and maybe others who did the upper bushing conversion but those were not promoted or much known about in this neck of the woods. Those two and the factory relief valve kit were the only options I am aware of until Craig and Eric came out with the Olds conversion a few years ago.

I lost my post.

So this is short..the Melling pump possibly could be modified to add vacuum unit..

The shaft goes out bottom.. Would depend on if vacuum pump would interfere with oil screen..

The Melling is a smaller pump than Packard..but same length.

I lost spark with my 400...but the Melling pumps up turning engine over...where Packards pump takes awhile..

I had an egge oil pump with no problem.

Others mods...clacking..

Relative to the original post:
I would not let 'oil pump" issues sway me away from buying any Packard.
Altho there mite be people who inntend to buy a classic car expecting a perfect engine and do not want to deal with any major internal engine problems. Such people probably need to find a different hobby. i.e. avoid vintage vehicles completely.


In terms of the oiling issues of the V8 it is Owen Dyneto above that says it best: " ...there is no simple anaysis that explains everything...."

HOWEVER, the Olds pump conversion seems to solve the problems rather fast.

BOTTOM LINE: IT is quite possible that any deficencies of the OEM V8 pumps were simply due to a lack of quality control AT THE FACTORY. A quality control problem that did NOT necessarily effect every pump but has obviously effected ENOUGH pumps to cause numerous complaints.

But the Olds coversion seems to be the quickest, cheapest and most reliable solution for the v8 oiling problems, espeialy the lifter clacking.


Let me put it this way:
If u buy the car and it exhibits no oiling problems then there is not a problem and don't fix it.

IF is DOES have oiling problems, especialy lifter clatter, then do the Olds conversion.

Here. let me put it a third way:
If there isn't a problem, then don't fix it.
If there IS a problem, then fix it with the Olds pump conversion.

Well.

Ran the 400 for few minutes. I can say no start up clacking..oil pressure up. With Melling..

Just my two cents worth - I've just done the Olds oil pump conversion on my 374 and it is positively brilliant I did about the hardest test you could for an old car - I drove it downtown in rush hour, no low pressure issues whatsoever.

Now, adding something a little more illuminating here - my 61000 mile 374 measured .045 wear on the mains. The bearings were absolutely munted. Interestingly it had had "020" stamped on the counterweights, so it looks like it's already been ground sometime in the past.

Had a spare motor that came out of a 58000 mile original car - BUT this one owner car had been parked up in 1966 (levelizer issue). The crank was around .002 wear so in really good shape, though again the main bearings were through the copper to the backing.

What this tells me is that a low owner car is more likely to have had things like regular and more frequent oil changes and possibly more sympathetic driving that would've helped considerably to offset massive wear.

I get the impression that the oil pump (and possibly the galleries) were on the marginal side when designed (fine for a less stressed low comp straight eight with double the sump capacity though) and with old unchanged grubby oil (especially the raw crude that was available back in the day) the V8 just clogged the galleries and the pump a little too much and with a revvy, High comp V8 that people drove pretty hard it just pushed the marginal capacity oiling system over the edge.
The oil pump conversion kit and with vastly superior oils available today it's really now no issue.

You could even think ditching the silly bypass oil filter that stresses out even more the oiling system. Filters about 10% of your oil and syphons off a litre out of one head that the poor old oil passages have to cope with. Dealer handbooks advise that after installing a bypass filter to advise the customer not to be concerned that the oil pressure warning light now comes on at idle. Friend with an early Landy had a measured pressure gauge and after removal of his bypass filter oil pressure raised 9 - 10 pounds at warm idle. No wonder there were oiling issues.

Merry Christmas and Happy New Year too :)