82 c20 dieseling and white smoke where to start?

Discussion in '1973-1987' started by kinger79, Jun 24, 2010.

  1. kinger79

    kinger79 Member

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    I have an 82 c20 with a 350 that started dieseling when I shut it off. It also belches a puff of white smoke during tranny shifts. It seems to start and idle pretty well. I still have original rochester 4 bbl on it. the vac lines are pretty bad. was just looking to get some advice on best place to start tackling this one. I assume new vac hoses and timing check would work wonders, will this take care of white smoke also or should I be looking for something deeper?
     
  2. weider1717

    weider1717 Member

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    could be plugs or idled a tad too high..
     
  3. Pontiac1976

    Pontiac1976 Member

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    I would check timing and if the vac lines are really old leaking I would change them all. Then check the carb maybe time for a re new kit (new gaskets tune up time. Do all the basic stuff set trimming. Let us know what you do how it goes. Good luck. Oh you have checked to make sure your plugs are not burning any rad fluid. The rad not low on fluid.
     
    Last edited: Jun 25, 2010
  4. kinger79

    kinger79 Member

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    well I changed all the vac lines and checked the timing. the plugs are new as well as wires, dist, ect... truck runs much better :D I think it is time to tackle carb next. The truck had set idle for quite a few yrs so not surprised to start having issues after running it for a while. It is still belching a small cloud of white smoke when u shift? carb?? Can't find any reference to that prob in the service manual. It has hd 350 in it so no egr valve don't know if that make a difference or not. Thanks for the help guys
     
  5. bodycount

    bodycount Member

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    the oil leak you are referring to would be your valve seals :D seals!!! ar ar ar
     
  6. Pontiac1976

    Pontiac1976 Member

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    Yes it could be valves seals that smoking coming from, not to hard to replace pretty cheap as long as the valves guides are not leaking. If the valves guides are leaking then you will have to take them off have them sent out to shop or buy new heads so it's up to you at that point to think of up grading the heads or have them old one reworked.
     
  7. kinger79

    kinger79 Member

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    maybe leaking a little oil but not enough to warrant the white smoke I see??? I don't believe, although i could be wrong which is why I am on here asking u guys hehe It really isn't using much (any) oil. The white smoke i am referring to is a cloud/puff after acceleration and you let off clutch and shift and accelerate..white smoke... goes away again. idle is clean and exaust while accelerating is clean.
     
  8. kinger79

    kinger79 Member

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    :mad: Pontiac...u were right. I pulled #1 plug and was all pitted #$!% rest of the plugs seem ok. no oil in radiator and no water in oil though. antifreeze is foamy though...headgasket or cracked head?
     
  9. Pontiac1976

    Pontiac1976 Member

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    Sorry to hear that hope it's hopefuly it's just the head gasket not the head.
     

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