Compression *UPDATE*

[DHMag]

ok, i ran another compression test just 30 minutes ago, per AutoSHOs advice. this time, all plugs removed, WOT, dry test only. here are the results:

Cylinder #4..|..Cylinder#1
215............|...220
__________|______________
Cylinder #5..|..Cylinder #2
205............|...220
__________|______________
Cylinder #6..|..Cylinder #3
215............|...220

a few pre-test observations: the SHO sat without being driven for a few days, when i started her, she puffed blue smoke out the tailpipes. i also removed the crossover tube and didnt see any oil puddling occuring. just tarnish from the oil once used in it, and a bit of dirt/carbon. nothing out of the ordinary.

the compression numbers look better and are within 10% variation.

with the puff of smoke i got from starting her after sitting for a few days, that indicates valve seals to me..anyone else ?

<small>[ September 01, 2003, 12:02 PM: Message edited by: DHMag ]</small>

 

[luigisho]

Those numbers look much closer. They seem high for that many miles. Not a bad high number but higher than I expected.

<small>[ September 01, 2003, 12:10 PM: Message edited by: luigisho ]</small>

 

[DHMag]

luigisho:
Those numbers look much closer. They seem high for that many miles. Not a bad high number but higher than I expected.

yeah, they seemed a bit high to me as well. i ran 3 tests on each cylinder and came up with the same number 3 times. well, i was also fighting a faulty schrader relief valve on the gauge, so a few cylinders had 4/5 tests ran.

 

[olympic]

That's much better! And your right, puffs of smoke at start-up generally indicate bad valve seals.

 

[DHMag]

olympic:
That's much better! And your right, puffs of smoke at start-up generally indicate bad valve seals.

the reason i hadnt seen the puff at startup before is because its my daily driver. started at least once every 8 hours. but i now have a second vehicle, i can park the SHO and do more diagnostics on it without having to worry about getting it back together in time for work, et al.

 

[AutoSHO]

Did it puff blue smoke after you ran the compression test? If you ran it wet thats definately ro be expected. Those numbers are pretty much what I expected. Sounds like a pretty healthy SHO as far as compression goes. A puff of blue smoke is definately indicative of bad valve stem seals and/or worn valve guides. I think you're on the right track rebuilding the heads.

 

[billyshoe]

on a 3.0 w/175000mi burning up to 1 quart every 150mi my compression readings were better. 240 being the lowest & 255psi the highest. this motor has been ran at high rpms for extended periods countless times. It still made hp.

 

[DHMag]

AutoSHO:
Did it puff blue smoke after you ran the compression test? If you ran it wet thats definately ro be expected. Those numbers are pretty much what I expected. Sounds like a pretty healthy SHO as far as compression goes. A puff of blue smoke is definately indicative of bad valve stem seals and/or worn valve guides. I think you're on the right track rebuilding the heads.

Chris,
the puff of blue smoke was 2 days prior to any compression testing. as i said, the car sat for a few days without being started. and when i started it, it puffed blue smoke. after i ran the wet compression test, i puffed lotsa smoke, but that was expected.
i hope everything is cool between us ?

 

[DHMag]

billyshoe:
on a 3.0 w/175000mi burning up to 1 quart every 150mi my compression readings were better. 240 being the lowest & 255psi the highest. this motor has been ran at high rpms for extended periods countless times. It still made hp.

well ****, of course you had good compression, your cylinder walls are constantly coated in oil, burning a quart every 150 miles

 

[AutoSHO]

billyshoe:
on a 3.0 w/175000mi burning up to 1 quart every 150mi my compression readings were better. 240 being the lowest & 255psi the highest. this motor has been ran at high rpms for extended periods countless times. It still made hp.

2 words:

Carbon Buildup

 

[pjtoledo]

DHMag:

AutoSHO:
Did it puff blue smoke after you ran the compression test? If you ran it wet thats definately ro be expected. Those numbers are pretty much what I expected. Sounds like a pretty healthy SHO as far as compression goes. A puff of blue smoke is definately indicative of bad valve stem seals and/or worn valve guides. I think you're on the right track rebuilding the heads.

Chris,
the puff of blue smoke was 2 days prior to any compression testing. as i said, the car sat for a few days without being started. and when i started it, it puffed blue smoke. after i ran the wet compression test, i puffed lotsa smoke, but that was expected.
i hope everything is cool between us ?

Both of my SHOs, and I suspect many SHOs, will puff blue smoke if they are started and run for only a few seconds then shut off. The next startup will smoke, if it sits for a couple hours or more. If I let them run for about a minute or more before shuting down there will be no smoke at the next startup. Been that way since they were new. Anybody else see this?

How is your oil consumption? One does not rebuild heads for startup puffs of smoke. It's the consumption that matters.

Perry

<small>[ September 02, 2003, 11:37 PM: Message edited by: pjtoledo ]</small>

 

[billyshoe]

intake seals will yeild a puff at cold startup but if you're using an quantity of oil it won't be the intake seals causing the consumption. You can make yourself believe its the intake seals or some other pipe dream. but you need new rings.

 

[DHMag]

billyshoe:
intake seals will yeild a puff at cold startup but if you're using an quantity of oil it won't be the intake seals causing the consumption. You can make yourself believe its the intake seals or some other pipe dream. but you need new rings.

aparently you didnt see my updated compression numbers. and my numbers coincide with all of the others who have participated in my threads, except for you. i dont need new rings. i have one oil leak left, and thats the cam seals. but i doubt itll cause me 1 quart every 1500 miles, or 1 quart every 500 hard driven miles. when i park the car after driving, if i was burning oil externally, id smell it, but i never smell oil burning. if its not burning, then its puddling/dripping, and the underside of the car is dry and no puddles on the ground. from now on, you can keep your comments about my posts/situations to yourself, thankyoupleasedrivethru.

 

[DHMag]

pjtoledo:

DHMag:

AutoSHO:
Did it puff blue smoke after you ran the compression test? If you ran it wet thats definately ro be expected. Those numbers are pretty much what I expected. Sounds like a pretty healthy SHO as far as compression goes. A puff of blue smoke is definately indicative of bad valve stem seals and/or worn valve guides. I think you're on the right track rebuilding the heads.

Chris,
the puff of blue smoke was 2 days prior to any compression testing. as i said, the car sat for a few days without being started. and when i started it, it puffed blue smoke. after i ran the wet compression test, i puffed lotsa smoke, but that was expected.
i hope everything is cool between us ?

Both of my SHOs, and I suspect many SHOs, will puff blue smoke if they are started and run for only a few seconds then shut off. The next startup will smoke, if it sits for a couple hours or more. If I let them run for about a minute or more before shuting down there will be no smoke at the next startup. Been that way since they were new. Anybody else see this?

How is your oil consumption? One does not rebuild heads for startup puffs of smoke. It's the consumption that matters.

Perry

Perry, oil consumption is 1 quart every 1500 miles. YELLOW Check Oil Light comes on when im 2 quarts low. and i change my oil every 3K miles so its my Oil Change Needed indicator . i am rebuilding my heads because i am blowing something out the tailpipes(other than exhaust) under hard acceleration. its a constant occurance that i can make happen. cruise at 70 in 4th, RPMS about 3800...drop into 3rd and stomp the throttle and theres the initial cloud. hit 4th at 85 MPH and its constant and thick. another note, i cant see it during the daylight, its only at night when there are headlights behind me. also, itll only do it when the secondaries are open. additionally, ive removed the PCV hose and its ok. a trace of oil, but not saturated, no smell of oil. also checked the plenum runners and there is no oil puddled in there. so that tells me the rings are ok.

 

[billyshoe]

Hey, you have decided to stick you're head in the sand. that headwork will not give the results you're expecting.

 

[DHMag]

billyshoe:
Hey, you have decided to stick you're head in the sand. that headwork will not give the results you're expecting.

you should be more concerned with your 1 qt/150 mile oil consumption rather than my 1 qt/1500 mile oil consumption.

 

[autobahnsho]

i have one oil leak left, and thats the cam seals. but i doubt itll cause me 1 quart every 1500 miles, or 1 quart every 500 hard driven miles. .

So did you get your problems fixed?

I was doing a search for almost the same exact problem. Lotsa smoke, I had been running the car w/bad plug wires a few weeks. On the other hand, I don't think it's EVER gotten a valve adjustment, and I need to check that I didn't mess the timing up after this last cam seal replacement.

The real reason I'm posting, is I did my cam seals back in March. I did all three, and also the front main. Close it all back up and drive. The car was leaking ridiculous amounts of oil, and I lost mroe than 2 qts of oil in one week with less than 100 miles driven. I had to re-order the cam seals. It was also sending out huge clouds of smoke from the engine bay, as it was dripping on the catalytic converter.

I had rolled the front bank seal just a little bit on installation. Re-installed and it's good to go.
Yes a bad cam seal will cause massive oil leaks. :ruhroh:

 

[revhardSHO]

Perry, oil consumption is 1 quart every 1500 miles. YELLOW Check Oil Light comes on when im 2 quarts low. and i change my oil every 3K miles so its my Oil Change Needed indicator . i am rebuilding my heads because i am blowing something out the tailpipes(other than exhaust) under hard acceleration. its a constant occurance that i can make happen. cruise at 70 in 4th, RPMS about 3800...drop into 3rd and stomp the throttle and theres the initial cloud. hit 4th at 85 MPH and its constant and thick. another note, i cant see it during the daylight, its only at night when there are headlights behind me. also, itll only do it when the secondaries are open. additionally, ive removed the PCV hose and its ok. a trace of oil, but not saturated, no smell of oil. also checked the plenum runners and there is no oil puddled in there. so that tells me the rings are ok.

I cool running SHO will spew a lot of crap outta the pipes, so make sure its running at optimal temp.

Billy - Thats quite a bit of oil consumption - perhaps you have a leak too?

 

[SolidState]

my 91 with 140k had excessive oil blow by, but I was using a synthetic oil and it was in the pan for about 8 months.