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After a valve job, it appears that I have some valves that are not closing completely with a subsequent loss of compression once the hydraulic lifters pump up. Reading the section in the engine manual dealing with hydraulic lifters (after re-assembling the engine), it's obvious we missed a major step requiring tool J-2553.

Can anyone provide:

1. Information on the plug gauge from Packard tool J-2553 (to borrow, rent, buy) or,
2. The exact dimensions of the plug gauge or,
3. Any method of determining the correct valve length for a 356 engine without the plug gauge.

Thanks.

Yes, you absolutely, positively have to use the gauge. If all you did was hand-lap a few seats you might get away without it, but if seats and/or valves were machine cut and/or any valves replaced you need to establish the correct clearance (0.030 to 0.070 inch if I remember correctly). Rob Carpenter had made and advertised this and the other unit for the 51-54 Packard eights for many moons. I think you'll find his ad in the PAC newsletter. I had several of these in the tool box and if you don't find one elsewhere, send me a PM and if I can locate one we can arrange something.

Here is the online ad for this part. Packards International Northwest Region
packardsintnw.com/regional_projects.htm

I searched the Cormorant News Letter and couldn't find an ad from Rob Carpenter, but did stumble across the same ad for P.N.R. provided by Clipper47. Bottom line, the tool is on its way.

What a great website and great members. Many thanks to both of you.

O-D, et al: The person to whom you are referring to/looking for is Ron Carpenter,20 Los Ranchitos, Alamo, CA 94507, 925-933-1486. I got this information from the Packard Club directory.

JD, I sent you a question in PM.

Quote:

In case that other readers are interested, here comes the above announced
--> link to the online ad for this part.

Quote:

I must be missing something here. I will be doing a valve grind this summer on a 327 with hydraulic lifters. Haven't looked it up however I think with all engines,irregardless of manufacture that have hydraulic lifters, the valve clearance is 0. Also the plunger/piston inside the lifter must be depressed against the internal spring somewhat. For instance a chevy with adjustable rockers you first adjust to 0 clearance then take the adjustment one full turn past that to place the internal piston in it's correct operating position.
Your reference to 0.030 to 0.070 inches must be the clearance for adjusting for solid lifters.


Comments??

PLEASE - read the shop manual. The 0.030 to 0.070 isn't the clearance for solid lifters, you'd hear them 5 miles away at that clearance and the engine would run VERY poorly.

The hydraulic tappet only has a certain limit of range, that is it has a limit to it's up and down range. When you replace valves, cut seats for valve faces, etc. you change the distance between the stem and the hydraulic tappet and thus risk running the tappet out of range. Too little clearance and you're run the hydraulic body into the lifter body and risk breaking the tappet or the base, or jamming them together.

You REMOVE the tappet body, replace it with a gauge block, and grind the base of the valve stem to give the 0.030 to 0.070, thus insuring that when the tappet is reinserted the lifter's range isn't compromised; that is, the remaining gap is within the tappet's range of movement!!

Yes, when the hyraulic tappet is energized with pressured oil, the clearance between it and them is zero. But that's not the issue.

I made and sold these tappet gauge blocks many years ago. As I said in an earlier post, if you want to borrow one, send me a PM.

OK, I get it. in essence not any different than grinding the valve stem on an overhead valve engine with unadjustable rockers to the proper height.

Question, with proper valve stem height the plunger in the lifter is depressed and there is 0.00 valve clearance?