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Replaced my Blown Head Gasket on my 1953 Packard Convt.,
but not until I took the Head to a Local Machine Shop and it Machined, it was .0025(Thousands Off).

While the Head was at the Machine Shop, I Cleaned up all the Valves and Freed up All of the Hydraulic Lifters, taking each on apart and cleaning them up and putting them back together dry as per the Shop Manual.

I did a Compression Check and it Varied from 35 Lbs. to 60 Lbs. No Good! I then took about 16 Days and let each Valve in the Open Possition for about 1 Day, thinking that this would force the Stuck Valves to Close.

After all this the Compression came up from 5 Lbs to 15 Lbs. Increase with 2 of Cyclinders staying the same.

I get spark from the Coil, but when I take out the Spark Plugs there is no Smell of Gas on Them.

Can Anyone tell Me what I might be Missing?

Sincerely,
the4hundred
Steve

One recommendation.... check the torque on the head nuts again.

Also, check that there is not a false torque reading caused by nuts on the studs bottoming out. Even though you only took off .002 the head is still thinner. If the new head gasket is also thinner that would make it worse. Hopefully you also checked with the .002 removal that the valves had plenty of clearance to the head before torquing it down.

You didn't mention any other valve work such as grinding and refacing but if you did, was the plug gauge used to verify if any of the what could now be excess length of the valve stems needed removing.

It's unfortunately also possible that milling the head made it too thin so that the values are hitting when fully up, especially if it may have been milled in the past. I had that happen to one of my Packards and the lesson learned is that these heads really should never need machining as they are thin enough to be able to tighten down properly even if slightly out of flat.

A head that is two and 1/2 thousandths out of spec may not have needed surfacing. Did the valves move freely in the guides, sticky valves do not close well.

You did not mention if you inspected the valve seats in the block and the valve faces to see if they needed cutting. You did not mention lapping in the valves to insure a good closure???

Your explanation is difficult to follow.

NONETHLESS, I am assuming u have never heard this engine run and/or it quit running before u took it apart.

In that case it sounds like a broken or "jumped" timing chain and/or incorrect timing at the timing chaain and gears or maybe broken cam.

Bottom line: A valve TIMING problem.

" he Head to a Local
Machine Shop and it Machined, it was
.0025(Thousands Off)."

Yeah, who ever recommended the head milling needs to stay along way away from your car. That was completely UNnecessary

IF the lifters are adjustaable then maybe theyare adjusted way to tight or improperly adjusted causing the valves to hang open..

When I first replaced the Head Gasket, I cleaned up the Block and Valves Installed a New Head Gasket and the Motor Wouldn't even turn over. I removed the Spark Plugs and turned it over and Water shot out Several of the Cyclinder's. That is when I decided to take the Head to the Machine Shop and they told me it was Twenty-Five Thousands off(.0025).

I made sure that Number One (1) Piston was up and Rotor in Dist. Was at Number One Plug in Dist. Cap.

the4hundred

This car ran Great prior to the Head Gasket Going. I Bought this car fram a person that had it for Almost 30 Years. I contacted the person he bought it from and to my Knowledge it never had any Engine work done to it. It has only 96,000 Miles on it.