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-   -   SMOKE: i'm taking the VALVE COVER off again. what should i do whilst in there? (http://www.peachparts.com/shopforum/showthread.php?t=196114)

blankenship 08-03-2007 08:18 PM

SMOKE: i'm taking the VALVE COVER off again. what should i do whilst in there?
 
well, long story short, this MASSIVE amount of blue/grey smoke's just killin' me. driving to work this morning, i just felt like such a jerk, SMOKING THE ENTIRE STREET when pulling away from the stoplights, i had to feel just really bad for all the people i was fuming.

you can read my saga in the thread from this post,
or, i can just tell you that my '85 300TD smokes a LOT of grey/blue A LOT of the TIME. she does it when i start her up in the morning, and runs loud and like crap with very low power until she warms up. she does it EVEN when warm, though, she'll spew out a ton whenever pulling away from a stoplight. she does it when engine's warm and you re-start.

she doesn't have all that much blow-by, and has plenty of power when warm. i read a post here that makes me think it's gotta be valve-related even though i haven't noticed her using much oil...

i'm planning on taking the valve-cover off again this weekend, so thought i'd ask: when i re-check valve clearances, what else should i do? how can i tell for certain if the valve seals or valve guides are bad? how can i tell if i have a burned intake valve or if they're not seating correctly due to carbon crust?

SD Blue 08-03-2007 08:45 PM

If you were using a significant amount of oil, then I would think the valve guides would be suspect.

However, yours sounds like a fuel/incomplete combustion problem. If you saw a significant amount of carbon on the nozzle itself (as mentioned in your other post) then there could be problems with the prechambers which have small holes to pass the atomized fuel. Carboned prechambers could also affect glow plug operation.

With that much coking and carbon, has this car been run on waste veg-oil?

bgkast 08-03-2007 11:13 PM

When I had a tight valve causing a miss it made my car smoke quite badly. Listen to the exhaust at idle and see if it sounds even or if it sounds like old train... chug..chug..chug.

toomany MBZ 08-04-2007 07:04 AM

Quote:

Originally Posted by blankenship (Post 1582062)
i'm planning on taking the valve-cover off again this weekend, so thought i'd ask: when i re-check valve clearances, what else should i do? how can i tell for certain if the valve seals My vote. or valve guides are bad? Those too. how can i tell if i have a burned intake valve or if they're not seating correctly due to carbon crust?

You'll have to pull the valves, methinks.

blankenship 08-04-2007 11:06 AM

so is there a way to TEST for bad valve stem seals or improper seating?

SDBlue:
car's never been run on veggie. did you see the picture of the removed injectors here?
did they all seem particularly carbony for having 1000 miles on them? (they guys who pop-tested didn't mention it, but i didn't 'check the balls' while i had the injectors out). more importantly, what's the <i>solution</i> or process to cleaning or verifying the prechambers?

BGkast:
I can't really say she sounds like a train or that she has that chug. More like just LOUD and klacky, and makes you wanna drive off in a hurry so you're not associated with the plume of smoke...

JimmyL 08-04-2007 11:15 AM

I'm having flashbacks.........:eek::eek:
I miss that old wagon! :( {bottom car in sig.}

bgkast 08-04-2007 01:55 PM

Quote:

Originally Posted by blankenship (Post 1582539)
so is there a way to TEST for bad valve stem seals or improper seating?


Try a compression test.

blankenship 08-05-2007 07:08 PM

yeah, but
 
how can i tell for certain if the valve seals or valve guides are bad?

how can i tell if i have a burned intake valve or if they're not seating correctly due to carbon crust?

should i just replace the stem seals? can i do it, or is it best left to a pro?

bgkast 08-06-2007 12:56 AM

I doubt it's the valve stem seals since it smokes all the time, not just when cold. If you have low compression on one hole pressurize it with compressed air and listen to the intake, exhaust and crankcase vents to see if you can hear where it is leaking from. Can't really tell if a valve is burnt or carboned up without pulling the head, but if it has been sticking open for awhile it is probably burnt. Perhaps your turbo seals are leaking?


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