Now I am confused!!!!!

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Jun 25, 2003 08:52:20
Gary Lloyd

Like I say, thanks everybody!!! Now i am totally confused!! I did a compression test on her this morning and #1- 125lbs, #2-145 lbs, #3-145 lbs and #4-145lbs. Okay, number one is weak, which I suspected, because it was weak a chris's yesterday! So, now I want to see if a valve got damaged when I lost the C-clip. Now I do it wet, using 5/30 oil. Here are the wet numbers #1-145, #2-over 300( pegged the gauge) #3-200 and #4, gauge pegged again!! What is going on???? How the heck could it get up to 300 lbs???? I believe that I should pull the head to check the valves in #1, but I don't know what to think about the rest???

Jun 25, 2003 09:55:43
John D. Weimer

Get a fitting you can screw into a spark plug hole and put an air hose fitting on. Put each cylinder , one at a time of course, past TDC on compression and shoot the air to it. That will tell you where the compression is going without taking anything apart. Some ring leak-by is normal even on a good cylinder, but any excess can be heard wherever it goes. Sometimes out the carb(s), exhaust, or out the oil filler hole; have the cap off while doing the test. The fitting is available wherever KD, Lisle, or Mighty (HELP), items are sold, NAPA has them too.





Jun 25, 2003 10:30:13
tony barnhill

I'd take the valve cover off & get a blast of air/oil right in the face were it me....I prefer to see rather than listen...
...Gary...are you sure its a valve problem? &, the rings should be seated by now....so, what did you reuse from your old engine & what's new?
1) is it your old pistons & a new block? or, your old pistons & your old block?

...&, you did something wrong...couldn't be 300...however, dry compression followed by rise when checked wet usually means rings (?, I'm trying to remember...rings, valves, rings....damn, a blank!)

....however, do i remember somewhere in all the posts that you're using a new block with your old pistons?

Jun 25, 2003 11:28:05
Gary Lloyd

Nope!! I used new pistons and a new block!! The notable thing is that the compression never came up to snuff!! It only came up to 145lbs!! The other notable fact is that is the cylinder that the C-clip and rings broke in!! They must have gone out the exhaust!! and the only thing that is common with the old engine is the head!! Also at chris's yesterday we did find bronze in the oil, which to me, could indicate a bent valve and wear on the bronze guide!! How could I do a compression test wrong??? Screw the gauge in, crank it about 12 times and go out and read the gauge, right????
JDW, good idea, but my compressor isn't at home!!! I do have the fitting, I made it myself years ago

Jun 25, 2003 12:21:50
tony barnhill

So, Gary, the short block in your car right now is not the short block you built & drove to chris'?

Jun 25, 2003 12:50:11
John D. Weimer

No point in taking the cover off when doing an air check. Leaking air will go out the exhaust, carb, or, if it's rings, up through the push rod holes. You'll hear a difference and know where it's from because you're on only one cylinder at a time.

Gary, I made my fitting to, about 35 years ago.

Jun 25, 2003 13:34:07
Gary Lloyd

Which way to chris's??? It is not the one i drove south with, but it is the one that i drove from Boise to Pendelton!!

Jun 25, 2003 13:38:21
Jim Hanks

Good to hear you got home o.k from the wild and wooley back country of Pendleton.
Your latest post is quite amazing! The compresssion test pattern fits what we thought at Chris's on the 23rd, if you wouldn't have those big #s on all but #1 following the oil check. Thats to the limit of my guage, so I assume you are pinning the needle. As I recall the 18GB compression when new is @ 160lb. ( HC engine )

Dumb question, but I'll ask it anyway...........any blockage in the exhaust system?

How did the car drive on the way back? Power? Oil comsumption?

This is a very interesting condition.............tell me more!

Jim Hanks ( red 66 "B" )

P.S. After all the excitement dies down, look at your used junk tach for the insulator pick up loop block and thumb nut. Thank

Jun 25, 2003 13:52:30
Gary Lloyd

Check the latest at the top!! CRAP!!!!!!!! It was still using oil!!

Jun 26, 2003 06:35:50
tony barnhill

So, a new short block (different short block than the one you initially left Canada with) is still using oil & has low compression on 1 cylinder?

Jun 26, 2003 14:56:39
Bud Goetzinger

How much oil did you put in for the wet test? Since oil isn't compressible, you may have completely filled the combustion chamber at TDC if you put in too much. I've never done a wet test but I would think a small squirt would be sufficient.

Jun 26, 2003 16:55:16
Gary Lloyd

You are totally right Bud!!! I put tooooooooo much in!! I had never done it before!!

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