Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

Dieseling in my new engine! help

Discussion in 'The Garage' started by sled_dog, Mar 22, 2003.

  1. sled_dog

    sled_dog 1 ton status

    Joined:
    Sep 3, 2002
    Posts:
    16,870
    Likes Received:
    0
    Location:
    Austin, TX
    My brand new completely rebuilt 355 has a problem with dieseling when I shut her down. If I have just pushed it pretty hard and hot before I shut it down it diesels. Like tonight I came home and drove up this like 1/4 mile long pretty steep hill at like 60mph in 3rd gear. Probably pulling close to 4000 rpms up it. I get home and shut it off and it diesels. Anytime I push it like that then shut it off it does this. Think maybe its getting so hot it keeps combusting? Not like its carbon buildup I mean its a brand new engine. I run 89 octane doubt thats the problem though.
     
  2. BowtieRed

    BowtieRed 1/2 ton status Author

    Joined:
    Dec 31, 2002
    Posts:
    1,776
    Likes Received:
    0
    Location:
    Winston-Salem, NC
    my BRAND NEW GM Goodwrench 350 does that too- i think since everything is brand new and perfectly lubricated and nothing chipped or anything and the compression is only about 8.4 it' does that. that's my theory.





    well that and i'm terrible at tuning my carb.
     
  3. Hossbaby50

    Hossbaby50 3/4 ton status

    Joined:
    Sep 1, 2001
    Posts:
    8,972
    Likes Received:
    0
    Location:
    Peoria, AZ
    Back the timing down a degree or two. I also have problems with dieseling in AZ during the summer if I push the motor fairly hard. But only during the summer when it is 100+ degrees. Otherwise it never does it.
     
  4. sled_dog

    sled_dog 1 ton status

    Joined:
    Sep 3, 2002
    Posts:
    16,870
    Likes Received:
    0
    Location:
    Austin, TX
    I need to simply set my timing /forums/images/graemlins/crazy.gif i have been driving for a week on the timing we set by ear. Our gun is broken so yeah can't set it. I know its not right cause it doesn't start perfectly and if you really jump on it it breaks up a little. THat and so far I am getting 6mpg /forums/images/graemlins/shocked.gif
     
  5. Hossbaby50

    Hossbaby50 3/4 ton status

    Joined:
    Sep 1, 2001
    Posts:
    8,972
    Likes Received:
    0
    Location:
    Peoria, AZ
    Ya, if you are having problems starting and stuff I would back the timing off some. I bet that solves the dieseling problem. If not, after you get on it a little cruise for an extra minute or two to help let the heads cool off some. Also you might try some of that Water Wetter stuff. It helps to cool down the engine temps.
     
  6. HarryH3

    HarryH3 1 ton status Author

    Joined:
    May 31, 2000
    Posts:
    10,384
    Likes Received:
    2
    Location:
    Georgetown, TX
    Having the idle set too high will contribute to run-on after shut down. Many carbs had a solenoid that was entergized when the power was on, to set the idle. Then when the power was shut off, the solenoid would retract and close the throttle blades all the way. That helps alot, when it's set up right. /forums/images/graemlins/thumb.gif
     

Share This Page