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.

engine manufactured to run on leaded fuel

Discussion in 'The Garage' started by rick88blaze, Feb 8, 2006.

  1. rick88blaze

    rick88blaze 1/2 ton status

    Joined:
    Jan 24, 2003
    Posts:
    2,342
    Likes Received:
    1
    Location:
    Knob Noster, Mo.
    The title is what I read on a for sale description on a '84 or '85 3/4 ton Suburban yesterday. This is on a military base so I can understand if the owner modified it if he was stationed in a country that still runs leaded fuel. But why would someone do that here in the states? :confused: The 'burb has 145K miles on it and some rust and good tires. He only wants a couple grand for it. I know if I bought it I would have to change the heads for unleaded fuel. Would there be anything else I would need to change on the engine to run on unleaded?

    Rick
     
  2. 1979jimmy350

    1979jimmy350 1/2 ton status

    Joined:
    Mar 24, 2004
    Posts:
    3,069
    Likes Received:
    0
    Location:
    Ann Arbor Mi
    If it is the orginal engine you should have no problem running unleaded with a tune up, the guy might have just changed the jetting and timing for leaded fuel, If it is a older engine you might just need hardened valve seats installed
     
  3. ryoken

    ryoken Puppy Fabricator Premium Member GMOTM Winner

    Joined:
    Jun 13, 2003
    Posts:
    29,624
    Likes Received:
    1,380
    Location:
    Jersey Shore
    sounds strange to me for that year... its just hardened seats from my understanding and that stuffs been out since the early 70's iirc... and no shouldn't affect anything else...
     
  4. sandawgk5

    sandawgk5 3/4 ton status

    Joined:
    Oct 28, 2003
    Posts:
    6,881
    Likes Received:
    1
    Location:
    Kitsap County PACNORWEST
    If it ran on Leaded then it will not have a Cat as leaded fuel and cats dont work at all together. Not sure of the physics behind it but I know if we take a vehicle to Europe when they only had leaded you had to remove your cat. All that said to say you might have to put a catalytic converter in your exhaust.

    Ira
     
  5. rick88blaze

    rick88blaze 1/2 ton status

    Joined:
    Jan 24, 2003
    Posts:
    2,342
    Likes Received:
    1
    Location:
    Knob Noster, Mo.
    No it doesn't have a cat on it right now but it does need a new exhaust system. I would like to buy it but can't afford it right now. If anyone around Omaha, Neb is looking for a tow rig this would make a decent one. :D

    Rick
     
  6. davesanrn

    davesanrn Registered Member

    Joined:
    Jun 12, 2005
    Posts:
    10
    Likes Received:
    0
    Location:
    Montana
    '85 is when trucks became required to run unleaded, ie got catalytic convertors.
     
  7. pauly383

    pauly383 Daddy383 Staff Member Moderator

    Joined:
    Jul 22, 2001
    Posts:
    16,217
    Likes Received:
    1
    Location:
    Mesa , Arizona USA
    Many had them before that , depended on GVWR .
     
  8. K5er4Life

    K5er4Life 1/2 ton status

    Joined:
    Oct 16, 2002
    Posts:
    1,456
    Likes Received:
    0
    Location:
    Bellflower, Ca
    Yup my friends '83 3/4 ton pickup has a cat, but my '86 K30 crew cab does not have cats. Yeah, dual exhaust and no cats from the factory.
     
  9. kgblazerfive

    kgblazerfive keymaster Premium Member GMOTM Winner

    Joined:
    Dec 2, 2004
    Posts:
    10,620
    Likes Received:
    610
    Location:
    Hooper, Utah 84315
    78 was first year for cats or unleaded fuel option on chevy trucks. If your gas cap is behind a door then its a unleaded vehicle.
     

Share This Page