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

Hi Folks,

So when I rebuilt my engine (1953 327 Cavalier, 5 main bearings) over this past year, I put in all new lifters, e.g. the hydraulic plunger, not the tappet. I didn't replace the tappets or the camshaft, though the shop refaced the tappets lightly.

Now about 200 or 250 miles in, I start to get tappet noise after the thing has been run for 45 minutes or so. Up to that point it is pretty quiet. Upon listening to it with a stethoscope, it seems to be limited to a certain couple of valves, I'm thinking 6 and 7, I can't really tell with the stethoscope beyond that.

I had checked the clearance with the handy gauge I got from the Pacific Northwest Packard club and everything was in spec, though perhaps a few of them were on the margin.

I started to notice this recently, and this last run it seemed like it had gotten louder, and it didn't clear up when the engine revs increased, like it had in the past. I guess I will try again tomorrow when I get home from work. The issue seems to coincide with when, at idle, the red oil pressure light blinks a little, which only happens after having run the engine for, again, 45 minutes or more. I recently did an oil change and replaced the oil I put in after the rebuild, 10W30, with 15W40 Diesel Engine oil. It seemed like that had improved things, or maybe I just hadn't driven it long enough.

Anyhow, anybody have problems with new lifters? Does what I said make sense? Any other remedies besides simply popping the head and replacing them, which doesn't seem to be a very fun job but hopefully I can accomplish without having to take off the manifolds.

Thanks in advance for all everyone's advice and insight.

JS

I'd check your actual oil pressure with an actual guage at the sender port. If something is off with the rebuild and you getting low oil pressure, that would only get worse when the oil gets hot.

Also check the oil line/filter plumbing to make sure nothing was assembled incorrectly. The filter side of the line should have a restrictor so the bulk of the oil goes to the lifters. If the restrictor is missing or the assembled incorrectly so the restrictor is on upper end side, then you could be starving the lifters. Start with a pressure reading just to see where you're at hot and cold.

Hi JS,

I had my 1954 359 rebuilt, including all new lifters. Two of the lifters were noisy after the rebuild and I had to have them replaced. Financially painful!

Good luck, Les

Did you use the special tool for checking clearance before putting in ths lifter insert? If not, the valves may be out of adjustment so will require disassembly and grinding to get the proper clearances.

Yes I did use the special tool, which I got from Pacific Northwest Packard club. Everything was in-spec though some were perhaps on the margins. I had checked oil pressure early on with a mechanical gage. I am going to install it again, perhaps temporarily in the cab.

Worn or pitted guides and valve stems will cause what sounds like lifter problems, but usually not so temperature sensitive. Of course if the parts are new this is not the cause. I did valve work with the manifolds in place working under the fender.

I reattached my mechanical gauge (to the last oil gallery plug at the rear of the engine on the passenger side) and ran the engine for about 30 minutes, until I could get the lifter to tick again just enough to hear. Oil pressure held steady at 40 psi. I think when it gets real good and warm after 40 minutes or so the oil pressure might drop down to a bit less than 35, when the little light will blink a little at idle (depending on how low I set idle).

Good thing is that I believe I have isolated which lifter it is. I have a couple of spares lifters so I will investigate replacing that one. Hope I can do it without taking the manifolds off.

Yes, you can easily replace the hydraulic units without having to remove the manifolds. Even for a full valve job they do not have to be removed.

Oil pressure sending units for "idiot light" systems are usually designed to trigger the bulb to flicker at about 5-10 psi.

Good point. I think I will try running it one more time with the oil pressure gage attached and see if I can get a reading when the light starts to flicker. Thanks again.

Don't these engines have an oil pressure cut off at 35 PSI? So would 40 PSI mean that the relief valve isn't functioning?

And if the dash light is blinking at 35 PSI, then that would mean the sending unit is bad, correct?

For reference, I installed a mechanical oil pressure gauge under my dash and it reads between 30-35 when first started, then will drop to 18-20 when warm at idle. When driving it's up around 25-33 depending on speed. I have mechanical tappets, running 15W-40 oil.

-Kevin