Packard Forum Index » V-8 (1955-56)

Ran a compression test today with these results: (from 1-8)

150 145 135 140 150 140 125 145

Number seven is the cylinder with the bad lifter.

We are going to see if changing lifters makes any difference....

On the whole, seems decent for 81,000 miles.

Anything simple that can be done to remove carbon build-up?

Used 5 containers of sea foam last year (per instructions, in gas only) and concluded it was probably snake oil...

Anything bothersome here? It seemed good to me.....

Numbers look fine except maybe for that one somewhat low cyinder but IMHO I wouldn't go to all the trouble of trying to remedy that one.

I agree. How do you know the lifter is causing the trouble? Seems to me not enough tests done to determine problem or cause of low compression. I would persue getting more tests from a professional mechanic.

Interesting that the cylinders on the RH side only vary by 5 lbs from high to low, but the LH side high and low have 25 lbs difference. Is it typical for one side to wear more than the other? I would think the difference could be attributed to crankshaft rotation and cylinder/piston oiling and not the valves.

(o{}o)

remove carbon,

I think back in the day, it was rice, down the carb.

Quote:

I don't know that it is, however the car went in for new lifters and the lifter issue was on the low cylinder so it seemed to me that since that obstacle was being addressed, all my other issues would be cured.....

"To think, perchance to dream..." or something like that. Whatever....

In a somewhat ideal world, I'd do the engine and the trans and maybe the rear end just because.

In the really ideal world someone would take care of all this and more for me....

Meanwhile, in this world, we do what can....

Sounds like a bunch of mumbo jumbo or what we call bullshxx. Stick to finding cause of problem and then fix it. The theory of replaceing parts in hopes of fixing problem is very time consuming and costly, especially with old cars.

Dallas wrote:
"The theory of replaceing parts in hopes of fixing problem is very time consuming and costly..."

That quote is probably the most brilliant of wisdom ever bestowed in the history of civilization.

I mite add to that statement:

"... and usualy does not correct any problems or only creates worse problems, especialy when dealing with the obsolete".

Dear Pat:

Okay you'd like to figure out what is going on inside your motor without a teardown.

Those two cylinders may be low from the valves being open during extended storage.

Take a spark plug to an experienced auto supplier and buy an air test adapter. This will allow you to fill the cilinders with compressed air to determine the nature of the leak.

If you don't have a compressor you can rig that thing up to take air from a tank or even a tire.

Do the test with each cylinder near TDC

a) hissing through the intake - valve
b) hissing through the exhaust - valve
c) hissing through the oil fill - rings
d) bubbling in the coolant - head gasket

Compare the results to your best cylinder. You can buy a gauge to measure percentage leakage if you want to get fancy.

Item C can be determined using a wet compression test as well.

Hope this helps.