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Smoke at start up, valve guides or piston rings?

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Old 02-08-2011, 06:55 PM
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Originally Posted by Superhero
Nope, that metal is part of a band that goes around the valve seal. It helps the rubber to keep its shape. Gimme a sec I'll post a pic of a new one. Somehow that piece of metal snapped, and I really hope I can figure out why. I don't think some burrs on the valve stem would have caused that kind of failure.

Heater control valve smeater control valve! Thanks! Maybe it was ready to go. That might explain why my heater has been lacking a little bit lately... Now to buy a replacement.
just by pass the valve with tees and coupling work just fine with out the valve
Old 02-08-2011, 07:10 PM
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I'll look into that, thanks!


Originally Posted by freegdr
just by pass the valve with tees and coupling work just fine with out the valve

Here are the comparison pics.
Attached Thumbnails Smoke at start up, valve guides or piston rings?-img_1034.jpg   Smoke at start up, valve guides or piston rings?-img_1035.jpg  
Old 02-08-2011, 07:20 PM
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ok it keeps the seal tight on the stem to limit the oil from running down the stem
Old 02-08-2011, 07:24 PM
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Yarp!

Originally Posted by freegdr
ok it keeps the seal tight on the stem to limit the oil from running down the stem
Old 02-13-2011, 07:24 PM
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I replaced the seals on #1 today, as well as the exhaust seal on #2. The 3 seals I have pulled so far have had broken metal bands. I hope I can find them all or I'll end up with a wrecked engine sooner or later.

The intake retainer on #2 is stuck. Anyone got some ideas as to how to unstick it? One person recommended taking a screwdriver and placing it against the valve stem under the retainer, then lightly whacking it a few times with a hammer. I did this to #1 and ended up with some small gouges in the valve stem.

I knew that was a bad idea before I did it; I should have known better. Is it possible to smooth out a valve stem while it is still in the head, which is still attached to the engine? The gouges don't have any sharp burrs or edges, but it'll still wear out that seal quickfast if I don't figure something out. I also wouldn't be surprised if hitting the stem laterally might have caused the guide to wallow out a little.

Otherwise, everything looks to be in great shape. I might have mixed up the rocker arms on #1, and maybe put a pushrod in upside down. I know it doesn't matter when the engine is new but will this cause any problems on a high mileage engine?

Thanks!
Old 02-15-2011, 09:05 PM
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I got it all put back together today. The #6 cylinder intake valve seal wasn't even seated, so that's where my troubles were. Also, the tick that would show up under heavy acceleration is significantly reduced, though I now have a new tick. Gonna call it a day and figure out that later. I'm just happy everything is running now. So long as the valve seal on #1 doesn't give out due to the dinged valve stem I should be good to go for awhile.
Old 02-15-2011, 09:49 PM
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as for the knick try a little emery cloth and smooth it out dont sand enough to create a flat spot as for the mixed up rocker ive put a lot of engines back to gether that have came in a box and never had a problem you should be fine glad to hear its done
Old 02-15-2011, 09:59 PM
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I don't feel like pulling the cover back off anytime soon. The valve seals are cheap, so if I find that it wears out from the knicks I'll smooth the stem out then. I have a feeling it'll give out sooner rather than later anyway... oh well.

I almost left my 1/2" ratchet attached to the bolt on the front of my crankshaft. I'm glad I dropped a valve cover bolt because I would probably have totally forgotten about it until I went to the the engine over.

The metal bands on all but one of the old seals were broken in half. I could only find a couple of the pieces so I guess they broke off and made their way through the engine before I bought it. I am a bit paranoid about that but nothing I can do without pulling the whole engine apart, and that's not happening any time soon.

I am a bit concerned about this new tick. It's quite loud, even at idle. Grr.

Thanks for all the help from everyone.


Originally Posted by freegdr
as for the knick try a little emery cloth and smooth it out dont sand enough to create a flat spot as for the mixed up rocker ive put a lot of engines back to gether that have came in a box and never had a problem you should be fine glad to hear its done
Old 05-02-2014, 05:45 PM
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Default 94 sport 234k miles & pourin smoke when warmed up & on startup

Originally Posted by mopwrd340
i use to have a 94 cherokee that would smoke when it was cold and lightly smoke when warmed up. i cleaned out the ccv system replaced the oil soaked air filter changed the oil and added a quart of lucas . within a week stopped smoking when warm saw a little smoke on cold start even passed emissions . this thing had 225,000 on it its an idea if you dont have a lot to spend in it right now
I haven't really driven her a whole lot yet (-50 miles) cause valve gasket was crap & bolts were just finger tight on top of broken leaf springs on both sides. Those issues were addressed with new oil & filter & air filter & spark plugs. Was throwing blue smoke on start up then was fine, but got new tires today & she got all warmed up & was pouring massive smoke.
My question is piston/compression rings or valves leaking? there was also a streak of blowback on the air filter when i changed it, looked like #3.
Love a straight 6 cause theyre east to work on, but tools & $ are an issue for now.
Any thoughts people? Thanx!

Last edited by AshleyL; 05-02-2014 at 05:47 PM. Reason: wanted to add i did fix the leaves as well
Old 04-21-2016, 07:13 PM
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Originally Posted by HCCAFan
When I had to replace valve stem seals, mine would smoke after idling for a long time.
After it was replaced or before?
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