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bing kunzig
07-28-2005, 12:58 PM
Thank you all for your input. Let me know what you think about how these figures may or may not relate to the knocking sound:

#1 140 #3 135 #5 145 #7 145

#2 155 #4 130 #6 140 #8 140

Mike Van Veghten
07-28-2005, 02:39 PM
1. Did you have the throttle blocked open? That can make a big difference.

2. Engine hot or cold?

3. With the exception of the open carburetor screwing with good readings, those numbers aren't bad. While they should be a little higher, they are fairly even.

4. Another way of ring inspection (without a leakdown gage set) is put some oil in the cylinders, spin the engine to distribute the oil better, then take another compr. reading.

whacker
07-28-2005, 05:27 PM
Well, I guess that pretty much shows that I am full of beans! Your compression is fine, consistent with all cylinders. Your knocking sound is something else.

Roscomacaw
07-28-2005, 08:59 PM
bing,
with the engine running, (using a pair of plastic pliers that are made for such), pull one plug wire at a time and see if the knock quits on any particular cylinder as it's wire is disconnected.:)

Miscreant at large.

1957 Transtar 1/2ton
1960 Larkvertible V8
1958 Provincial wagon
1953 Commander coupe
1957 President 2-dr
1955 President State
1951 Champion Biz cpe
1963 Daytona project FS

curt
07-28-2005, 10:10 PM
That sounds like good advice, pull one wire , from Mr. Biggs. Wrist pin and what else would this help diagnose?

N8N
07-29-2005, 06:46 AM
Wrist pin, loose piston, or rod bearing. (could be something else I guess, but that's what the "pull the spark plug wire" test will tell you)

nate

--
55 Commander Starlight
62 Daytona hardtop
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bing kunzig
07-29-2005, 01:44 PM
Thank you all. I think what I will do is have it checked out by my local Studebaker Service Center in Long Beach. I am taking it there anyway next week to have a power brake booster installed. Leave it to the experts.

buddymander
07-30-2005, 08:56 PM
I would take a piece of garden hose aboaut three feet long and hold it up to my ear and the other end down by the edge mof each cylinder. I kinda suspect numbers three and four for a wristpin knock or a piston slap contributing to the lower compression in those two cylinders due to piston wobble or lower piston height due to the excess wristpin clearance.

studegary
07-31-2005, 01:14 PM
I usually use a long screwdriver for a makeshift stethoscope.

curt
07-31-2005, 03:12 PM
Keep clothing ,shirt sleeves, tie, etc out of the fan belt when under a hood with engine running. Even long hair could get caught. I hit a finger once on a fan blade, I was in luck, no big damage.

PaulDriver
07-31-2005, 05:12 PM
quote:Originally posted by studegary

I usually use a long screwdriver for a makeshift stethoscope.


held to the occipital bone?

studegary
07-31-2005, 08:35 PM
quote:Originally posted by PaulDriver


quote:Originally posted by studegary

I usually use a long screwdriver for a makeshift stethoscope.


held to the occipital bone?



No, the large end pressed to my ear. (I think that it would be impossible to see where the other end of the screwdriver was if I held one end to the base of the back of skull.)