Compression?

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77mm - 25 Nov 2003 16:41 GMT

Got'z a 91 Geo Tracker 4X4 and get fang on a new timing belt. Drove up to
San Francisco last weekend and when I got back felt a miss on starting the
engine cold next morning. Checked compression and found 130 psi in # 1, 50
psi # 2, 150 psi in # 3 & 4. This morning going to check valve settings..,
yah think that will fix it..?! Li'me know.., OK? Monk from San Berdo..!!

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bulletsnbrains - 25 Nov 2003 17:50 GMT

Did you shoot a few squirts of oil into the cylinder and try the compression
test again? Results? The oil acts as a better seal around the rings. If the
compression rises, then you have a broken ring or worn out rings. If no
change, then valve sealing issue. Either burned valve, possibly worn guides
or carbon build up. Carbon chunks can lodge in the valve seat area and cause
a similar headache.

Luck,
Brian

> Got'z a 91 Geo Tracker 4X4 and get fang on a new timing belt. Drove up to
> San Francisco last weekend and when I got back felt a miss on starting the
> engine cold next morning. Checked compression and found 130 psi in # 1, 50
> psi # 2, 150 psi in # 3 & 4. This morning going to check valve settings..,
> yah think that will fix it..?! Li'me know.., OK? Monk from San Berdo..!!

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rnf2 - 25 Nov 2003 23:47 GMT

> Did you shoot a few squirts of oil into the cylinder and try the compression
> test again? Results? The oil acts as a better seal around the rings. If the
[quoted text clipped - 13 lines]
> settings..,
> > yah think that will fix it..?! Li'me know.., OK? Monk from San Berdo..!!

Compression probs can also be cracked head or blown head gasket.

And the oil test may not give the results you are looking for, the oil can
sometimes sit in dished piston heads and not run into the gap between the
piston and the bore.

rhys

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Mike Harding - 26 Nov 2003 19:14 GMT

Nahhhh guys, wasn't dat serious.., juz pull'd the valve cover and sure
enough the valves on # 2 were 'sticky' and so I readjusted the whole
thing..., runs like a top now! Thanks bros!! Did notice sort of sticky oil
'shellac' on the lifter rake though.., which I broke lose and cleaned up. I
might way to run some lighter oil or put some cleaner of some kind through
the system. Some real old dud (WW I pilot would you believe?) told me one
time they actually used 'caster oil' in the old days and it would 'shellac
up' the engines and they'd last forever.., err, at least until the next
war.., eh?! Later guys..., the Monk..!!!

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