Packard Forum Index » V-8 (1955-56)

With the minimal oil coming to the top end of the V8, wear down on the rocker pads is common, especially the rearward ones on the left bank and forward ones on the right bank. Many of them need to be resurfaced after as little as 50,000 miles. If not addressed, they will eventually wear into a "circle" that matches the end of the valve stem. Once this happens, the pad begins to catch and "wag" the valvestem sideways as it goes up and down; this will wear the valve guides out in short order.

THE FIX: disassemble the racks and resurface the rocker individually on a fine grit grinding wheel. Carefully rotate it back and forth against the wheel to follow the original curve of the surface, until all signs of wear are erased. Next, polish the surface on a wire wheel; repeat 15 times.

This fix works to repair even the worst of rockers, since the hydraulic lifters actually have about .200" of self adjustment, they will compensate for the removed material. Also, I am aware of surface hardening and going below it, but all I can say is this has always worked for me.

Joe H

Yes, the procedure u outine is what i have done to mine. BE SURE that the rocker SHAFT is clean INSIDE. What about valve guide wear on your engine????

Briefly: Packard V8 overhead valve train wear is due to a LACK of oil to the overhead. I drilled 3 of my rockers (3 on each head) just above the pushrod seat so that oil would squirt out like a Chevy V8. There is more to this procedure.
NOTE: The EARLY 55's Packard V8's had such a hole in the rocker but it was dropped in production about mid 55.

Keith -

Perhaps I can shed some light on the timeline and what was actaully done in this regard.

STB 55T-16 (dated March 28, 1955) advised of the elimination of said holes and provided instructions for plugging rocker shafts in the field. The reason for this was not made clear, but that info was again referenced in STB 55T-19 (dated May 23, 1955) concerning excessive oil consumption.

Then, STB 55T-35 (dated July 25, 1955) advised reinstatement of said holes, but with slightly smaller diameter, and recommended replacement of rocker shafts, inlcuding any that had been plugged, in the field.

There must have been some concern for excessive flow of oil, but they realized plugging those holes was an overcorrection.

However, premature wear at pushrod end of the rocker levers was never addressed in an STB, but in a confidential memo to Zone offices dated March 15, 1956. The cause was cited as an inconsistent hardening process, but new equipment and checks for production had been introduced. A new P/N was issued for rechecked and qualified parts.

Somewhere, I have a Parts Bulletin that requested dealers to return all old stock of said levers and reorder under the new number.

For worn valve guides, a good machinis will install bronze sleeves. My favorite machinist here in Kentucky won't even fool with oversized valve stems.

Also, I would not re-do a set of heads without having hardened exhaust valve seats installed. I once saw some seriously sunken exhaust valves in a Packard V8 within 40,000 miles, that was using OEM seats with modern gas.

Joe H

Where are u in KY ???? I'm 30 miles west of Nashville Tn. in WHite Bluff.

On the engine with 40K miles and sunken seats was it an original factory Packard head on the engine or a head that had been rebuilt before the sunken seats were discovered???? What kind of valves were in the head with the sunken seats???

The receeded exhaust valves were on the 56J I bought in 1986, with 81,000 miles on it. With just shy of 100,000 on the odometer, I pulled the heads and had a valve job done. Bear in mind the engine had had the shade tree rebuild at an estimated 75,000 in the late 1960s.
It was a basic valve grind, and maybe replaced a valve or two, I don't remember. When I tore it down again for a complete rebuild about 40,000 miles later, the exhaust valves were severely receeded, believe me!

When I rebuilt it, I had the hardened exhaust seats installed. Today, 70,000 miles later, it still idles smooth and gets as good of gas mileage as ever, around 20-22 at 65-70 mph. That is with the T85 and 3.31. rear end, with a final overdrive ratio of 2.38. I also run an AFB carb.

I live just about 115 miles up in KY, once you cross the state line on I65 coming from TN. Nashville is about 140 miles from here. The wife and kids are going to Japan for the summer, so maybe we can get together sometime. Perhaps a cruise in, or car show somewhere in between, or just a nice drive in my 56J or your Packard!

I have an old Volvo for bad weather, but when the weather is nice, its either the Harley or one of the 56Js. Life is good :)

Joe H

Were the valves in the receeded seats stainless steel???? More later, gotta run.