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Hi, I need some advice and direction with my 356 hydraulic lifters.

The engine has just been professionally rebuilt. The rebuilder checked the valve stem length with the Packard gauge as recommended in the Packard repair manual. The tightest clearance from stem to gauge was about .040, and the loosest was .070+.

I disassembled the lifters and cleaned them as described in the repair manual. They all seemed to work correctly.

The engine wouldn't start, and in the process of checking all assembly issues I found that the most compression I had was 50 psi, and it went down from there. The repair manual warns about assembling the lifters with oil in them as excess oil in the lifter might keep the valves from seating - hence little or no compression,

When I removed the lifters after discovering low compression, they did have oil in the body. I don't know if I added some oil when I reassembled the lifters, or if they pumped up while cranking. The valve springs, by the way, all look good, but were not load tested.

I tried to get new lifters from Canter, but they don't have any and don't expect any.

I could reassemble the valve system making sure there is no oil in the lifters. I am thinking that I would like to find someone with more experience than I have to check the lifters and the valve springs before I reassemble and hope for enough compression for the engine to start.

I discussed changing to solid lifters with Canter, but understand that I would also need to change cams. It would be best to get the hydraulic lifters working the way they should.

What are your thoughts and advice?

Also,I have a set of +.002 rod bearings and a set of standard knurled skirt pistons I would like to find a new home for.

I am looking for replacement front turn signal lenses also.

Thanks for your help. The owners forum is very helpful.

John Verity, Boise, Idaho

Hi John:

Actually that motor should run on 50 psi. I've seen those motors run on as low as 25-30. So I would double check the ignition timing. I never did a Packard motor that didn't start within 2 turns after carefully setting up the ignition system and filling the carburetor bowl. And that includes the hand crank models.

If you are concerned about overbuilt lifters you can check that using compressed air and an adapter. Put a cylinder at TDC and turn on the air. If air leaks out of the intake or exhaust the valves are indeed not seating. Or let the motor sit for a few days and try again.

Another option is to get some portable oxygen and dump it into the intake while cranking. Dumping propane into the manifold will also help.

I would squirt oil into the cylinders and recheck the compression. If the motor is tight compression will be lowered due to slow cranking.

Hope this helps.

Hi John; There is a installed spring height which I believe is 1.75 in. (I am on vacation and don't have any of my books) There is a gauge that is used to measure this, also the spring pressure should be measured on each spring. Do you have the washer that looks like star washer and goes on top of the spring? If the star washer is not on top of the spring and you have a weak spring along with high oil pressure the lifter will open the valve. It is necessary that you measure the space from the retainer to the block and then use shims to get the correct spring height. also have the spring pressure checked or buy new springs, you must also check the new spring pressure, as some times new springs are not as they should be. Any engine rebuilder should have done this. It is a big job, but needs to be done for correct operation. Hope this helps, Dell

Thanks for your advice about "leak down" testing. I will try that when the valves and head are back in place.


When I inspected and cleaned the lifters, the spring plunger didn't want to mate up very well with the lifter body. I was concerned about this.

Do you know where I could buy a few new or good used hydraulic lifters? Where can I buy new valve springs should I find some weak ones?

I have checked the cam and ignition timing several times, and will again confirm those settings when I reassemble.

I am getting the valve spring tension checked at the rebuilders now.

Thank again, John Verity

Hi, thanks for your advice. Yes, I do have the washers that sit on top of the valve spring.

I am going to have the rebuilder check the valve spring tension, and shorten up two valve stems that don't give enough clearance when measuring with the plunger gauge.

I have a few lifters where the spring plunger didn't seat well into the lifter body. Do you know where I can buy a few new or good used lifters and maybe new valve springs?

Canter does not have lifters. I didn't ask Canter about springs.

I will check the retainer to block distance with a caliper. What kind of shim do you use the adjust this distance, and where does the shim install?

Thanks for your help. I am anxious to get the rebuilt engine running so I can continue with the rest of the restoration project.

I am hoping to have the car running by springtime. I have a 47 Hudson super 6 2 door in addition to the 47 Packard Super 8 custom sedan. I will not be able to keep both cars and will need to decide which one to sell.

John Verity, Boise

The primary sources for valve springs are Egge and Kanter.

Seating the spring on the lifter plunger usually requires downward pressure while rotating.