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The results are in: Compression tested

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Old 07-29-06, 03:51 PM
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The results are in: Compression tested

if i did the test right... (which i hope i did)

here are the results

front rotor: 30-30-30

rear rotor: 30-0-30



think maybe i did the test wrong?
Old 07-29-06, 03:58 PM
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Warm (well, with those numbers that doesn't look possible) with the throttle held open in the trailing plug holes?
Old 07-29-06, 04:17 PM
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Originally Posted by SonicRaT
Warm (well, with those numbers that doesn't look possible) with the throttle held open in the trailing plug holes?

yea... we got her started and ran her up and down the road till she was at temp... then we followed the FSM as to how to do the compression test...
Old 07-29-06, 04:28 PM
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would she even run with numbers like that?
Old 07-29-06, 04:34 PM
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Was that with the Schrader valve depressed? If you let up it should climb with each compression pump. One chamber at zero is very strange. A seal ruins two chambers.
Old 07-29-06, 04:36 PM
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Originally Posted by TonyD89
Was that with the Schrader valve depressed? If you let up it should climb with each compression pump. One chamber at zero is very strange. A seal ruins two chambers.
One chamber at 0 usually means a blown side seal.
Old 07-29-06, 04:41 PM
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Originally Posted by TonyD89
Was that with the Schrader valve depressed? If you let up it should climb with each compression pump. One chamber at zero is very strange. A seal ruins two chambers.

the schrader valve being the valve on the tester... correct? if so... then yes... it was depressed


she does run but i have to keep giving her gas, or shell stall out... and when we went for a spin she felt very underpowered...
Old 07-29-06, 11:30 PM
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hmmm

this doesnt make any sense... the compression should be at least 85...correct?

why would the tester be only pulsing to 30?
Old 07-30-06, 12:05 AM
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Time to live up to your screen name. Side seals and corner seals don't break on original engines, though it does happen on occasion on engines that were improperly rebuilt.
Old 07-30-06, 01:52 AM
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Originally Posted by RotaryResurrection
Time to live up to your screen name. Side seals and corner seals don't break on original engines, though it does happen on occasion on engines that were improperly rebuilt.

i just hope i can afford it... i remember having a site bookmarked on what is all needed for the swap... but since that link went down a long while ago... im lost for the time being...
Old 08-01-06, 07:32 PM
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welp.... re-did the test using the leading plugs... and got the same result >.<

but.... if i release the purge valve on the compression tester, she jumps to 60~80psi

when i do the test, am i supposed to hold the purge valve in an watch for the pulses or just leave the valve alone and see how much pressure builds?
Old 08-01-06, 07:50 PM
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Well, to test the individual faces, you hold down the valve. It seems yours already failed that test, so theres not much point in doing another type of test. The one with the valve down is the one that really counts anyway. As for those numbers, it is theoretically possible that its just carboned all to hell and the seals are stuck. Mine got 30-0-0 numbers when the motor was like that. You might try soaking it in whatever it is thats recommended these days to remove carbon. I saw a thread on this not too long ago, try searching for "removing carbon" or something similar. It prob won't help, but it can't hurt.
As for rebuilds, kevin (rotary resurrection) is your best bet unless you plan on doing it yourself.
Old 08-01-06, 07:53 PM
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Holding the valve in shows the 3 faces on each common chamber. The bounces should be consistent and without skips, otherwise you have a stuck or broken seal. If you let the valve out and let the pressure build, you're getting a pretty accurate indication of the compression of the highest face in the chamber. Usually all 3 faces are even, therefore this is a good indicator of the health of the engine. However, if you have a single stuck, cracked or broken seal, this last test will miss that defect.
Old 08-01-06, 09:04 PM
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Originally Posted by Sideways7
One chamber at 0 usually means a blown side seal.
Ported motor?
Old 10-20-10, 10:24 PM
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bump for my own old thread...

think my car finally ate a seal... trying to nurse that stuck side seal back to health didnt work out too well i guess. probably went the last time i drove it.

guess ill be rebuilding sooner than later...
Old 10-20-10, 11:03 PM
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NOT BAD!!!! that ur motor lasted another 4yrs.
Old 10-21-10, 08:50 AM
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Originally Posted by gkarmadi
NOT BAD!!!! that ur motor lasted another 4yrs.
not too much of a surprise. 4 years of light usage considering she wouldnt hold idle and a number of other gremlins.
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