Packard Forum Index » V-8 (1955-56)

I'm new to this forum. There are so many topics to review and I'd be here forever looking for the answer to my inquiry.
Here's my question. On the 1955 V8(Patrician), a guy who has one once told me if you don't keep the oil up to the max(without over filling it) the engine will start knocking. Is that true for all the '55 V8's or just certain ones? If it's true, is there a fix to correct that problem?

I suspect he was not talking about traditional engine "knocks" which are usually either preignition (combustion) knocks or worn bearing (main and rod) knocks. In either of these cases the oil being kept at exactly the full mark has nothing to do with the cause or cure of those problems. I believe he may have been talking about hydraulic lifter clatter (sometimes called ticking); there is a significantly large pool of folks who have found over the years that running the engine about 1/2 quart overfull eliminates the problem. And there are others for whom it has not solved the problem. And there are others who have not had the problem.

And as for a fix, since the problem of lifter noise does seem to be hit or miss, some having it and some not, finding a reason and "fix" everyone can agree on has been elusive.

Over the years oil flow and the capacity and design of the original oil pump has been the primary suspect starting with Packards own service bulletins. Early in 55 production Packard made changes to the amount of oil going to various places and also issued a kit to lower the amount of oil dispersed to the timing chain so more oil would be available to the lifters. There was a later bulletin that air was getting into the pump so a kit to redirect the relief valve opening into the oil pool below the pump so air could not be drawn in thru the port was designed. It seems neither approach was the "fix". Much later a second design pump was apparently manufactured and put into service as a few have been found when rebuilding engines. The newer pump seems to be few so maybe there was not enough time to get many out or know if it solved the problem. I don't recall seeing anything where someone has completely documented what the differences are between the two pumps to know if Packard had found a definitive issue and designed it out. The overfilling to get the level in the sump higher thus alleviating the noise would tend to go along with the theory of air getting into the pump.

After Packard went away some thought pump bottom plate distortion and vacuum pump wear was the source of air entry. There have been several who offered services to eliminate the vacuum pump section and replace it with a heavy metal bottom plate to support the shaft and provide a non distorting leak proof cover. The Packards International Club was the largest source of the modified bottom cover pumps and for many years that approach was the go to for a "fix". Others thought that since the pumps did not have a proper bushing to support the drive shaft at the top, wear in the cast iron pump body around the shaft and the resulting shaft wobble was the source of air. There were some that offered a service of modifying the pump body to install a new shaft with upper support bushing. If I remember correctly I think there was a person who covered both possibilities by simultaneously doing the bushing and the bottom cover modifications to the pumps. I believe it has been reported that some engines with the PI pump have had intermittent lifter issues too so maybe not the "fix" but it also might be that some or all the other things Packard changed to provide more volume to the lifters had not been done in those engines.

The most recent addition for a "fix" on the pump is a kit to completely eliminate the Packard pump and bolt on an Oldsmobile pump. The Olds pump is modern and easily found, has a robust design for shaft support and comes in standard and high volume versions. The conversion was devised by some posters on this forum and has been available for a few years. So far it seems to have a lot of happy users. Unfortunately it also eliminates the vacuum pump and whether it has completely eliminated the problem is still an open question but results are good to date so we are all hoping it is the final "fix". Of course, the original Packard mods to oil distribution should also be done but the Olds pump does have more volume to spare if some have not been made.

What knock?

I blew a head gasket now I have a knock. Piston slap?.

It seems to quite down when warm. .

The olds..melling .. Pump works great no lifter problems.

I modified my Melling pump so that there is no clearance problems. .with The block.

G'day George D,

Sorry, can't contribute to this thread, instead I invite you to include your '55 Patrician and the '49 Super Eight(this thread) in the Packard Owner's Registry.

That happened to me. Oil a quart low, and the knocking was the BEARINGS. Had to have the engine rebuilt.

It must be the "ticking" vs. "knocking". All he said was as long as the engine oil is filled, you won't hear it. Now, he didn't mention overfilling it but then again, he was trying to sell me the car.

Did you rebuild it or had it done for you? I'm curious as to what that would cost. Before your re-build, did the car use/burn any oil?

A stuck lifter makes a knock. And it's loud.

Had the engine rebuilt over 20 years ago by a shop in Long Beach Ca. Engine never used any oil, and did not smoke, but the lifters were noisy even when the oil level was full. Engine only had 60k on it.