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I HATE MY TRUCK!

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by bigoltrux77, Aug 19, 2002.

  1. bigoltrux77

    bigoltrux77 1/2 ton status

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    just when i thought i had the timing pretty close, and it was actually running ok with some good acceleration, IT GOES BACK! I was driving it today and i had to stop a little more sudden than usuall, then it started to idle like crap, and started to bckfire out of the carb a whole lot! Now when i accelerate, all i hear is POP POP POP POP!!! Someone please help me. What do i do?
     
  2. mudhog

    mudhog THEGAME Staff Member Super Moderator

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    is the bolt holding the distibtor(sp?) tight? also check you vacume lines and make sure none are lose or leaking
     
  3. xnoahx

    xnoahx 1/2 ton status

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    I had that happening in my truck a while back, I fixed it by getting vortec heads and an HEI distributor.
     
  4. mudhog

    mudhog THEGAME Staff Member Super Moderator

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    from pm </font><blockquote><font class="small">In reply to:</font><hr />
    yes the bolt is tight, and the vacuum lines are ok. What else could it be?


    [/ QUOTE ]
    ok how many miles are on the motor? when was the last tune up? have you checked the fireing order 5&amp;7 get crossed sometimes (guilty of this myself lol) what carb do you have?
     
  5. tRustyK5

    tRustyK5 Big meanie Staff Member Super Moderator GMOTM Winner Author

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    A bad cam lobe will do the exact same thing...progressively more backfiring as the lobe gets 'rounder' and 'rounder'.

    Rene
     
  6. bigoltrux77

    bigoltrux77 1/2 ton status

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    if it waas the cam, then why would it just all of a sudden do it when i hit the brakes? The engine has 35,000 miles on it. The carb is 650cfm edelbrock with edelbrock intake.
     
  7. YtseJam

    YtseJam 1/2 ton status

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    If it was the cam it would do it all of the time. Double check all of your ignition components, check your spark plug gaps. Check the carbon button in the cap, check the ignition wires.

    What do you have the timing set at?
     
  8. mudhog

    mudhog THEGAME Staff Member Super Moderator

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    it may sound stupid but take a good look at the plug wires it could be that one has been burnt by the exhaust manifolds i had the same thing it would run fine then i would hit a bump or something and then i would get a loud poping noise and i found out that i had a burnt wire and it would get close to the manifold and ark across and make it run like sh!t and do the poping thing /forums/images/icons/frown.gif
     
  9. AussieK5

    AussieK5 1/2 ton status

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    Same here..I had a set of stock manifolds on my last blazer that would toast one of the leads and cause similar effects to whats been described. Just look for scorch marks around the exh manifold on 3/5 and 4/6 cylinders. I had to fab a small alloy shield to fix it, it turned out that a factory shield should have been in place.
     
  10. Blazer_Boy

    Blazer_Boy 1/2 ton status

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    What's pretty close? Keep it right on the factory specs. Change the mechanical advance weights and vacuum advance and then you've got some room to mess with the settings. GOOOOOD tune-up is a must. Get a can of stuff called Top Engine Cleaner from your GM dealer, or a can of Sea-Foam. Get the engine warmed up and dump that stuff right down the primaries while running. All the directions are on the can. Do that and an oil change and that'll clean that sucker right up. Could be a sticking valve, and that may help. Firing order goes clockwise 1-8-4-3-6-5-7-2. Odd cylinders are on the driver's side and go 1-3-5-7 from front to back. Passenger side is the even deck with 2-4-6-8. Note where #1 is on the distributor before yanking wires.
     
  11. loudnowlouder

    loudnowlouder 1/2 ton status

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    i made a very similar post about a month ago...set timing, shut off, timing goes out...
    turns out i got screwed over by a mechanic...he replaced a rear main seal for me cause i didnt have a good place to drop the tranny by myself...
    anyhow i brought it home and it leaked again right away...he swore his seal was fine, told me the next day the oil pump was bad....i called him on it and told him to keep his hands off of the engine, just replace the seal...(brand new engine...under 2k miles on it, oil pump steady at 65psi when driving)...

    anyhow he messed with the oil pump, didnt put it back in phase correctly, it was about 90 degrees off, then retarded the hell out of the distributor to get it to run...
    well it was actually still way off, i'd set the timing and it'd appear fine, but then it'd go out again...
    only way to fix it was crank the engine by hand to top dead center on #1, then with a long screwdriver turn the pump till i could get the rotor to hit #1 in the normal distributor position...
    then it was cake to fine tune it, and it hasnt lost a tune since then...

    but other causes of weird timing are worn cam like previously stated, vacuum leak with seriously mess with it, or a loose bolt on the distributor, but that wasnt the case on mine at all...
    but you might want to put the engine to tdc on #1 and check the rotor position, thats the sure fire way to get it set right...
     
  12. Grim-Reaper

    Grim-Reaper 3/4 ton status Author

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    Pull the distributor. check the roll pin that hold the gear on the bottom.....maybe it's missing the pin/pin sheared and the gear is turning.
     
  13. downtime2nite

    downtime2nite Registered Member

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    check the carb. if you slammed on the brakes maybe the float jammed or sumpin!
     
  14. Blue85

    Blue85 Troll Premium Member

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    Is the brake booster leaking all of the vacuum out?
     
  15. Silver84k5

    Silver84k5 1/2 ton status

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    i didnt read everyone elses post too carefully so i dunno if this has been said, Your Distributor could be a tooth off, or another thing to check would be take off the cap, take off the rotor, and look right under the rotor there are too Vacume advance weights they should not be over lapped at all anywhere, check those things as well if you havent all ready, the only reason i say this is cuz you basically desribed my problem and somone showed me this and it fixed it ;]] good luck and pls let me know what it was im always curious about that hehe
     
  16. Seventy4Blazer

    Seventy4Blazer 3/4 ton status

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    umm, he he, if ya hate it give it to me...
    hehe ... i doubt you will
    give ya my buick for it?
    no, ok...
    hey man dont feel bad. i have not driven OR STARTED my blazer in 18 months... BLAH.. it fkn sucks.
    grant
     
  17. bigoltrux77

    bigoltrux77 1/2 ton status

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    I figured it out! There were tow rockers laying in the valve bay area..im suprised it even ran. I put em back on and adjusted all the valves then set the timing and it ran great!! Bad thing is i took the covers off again to check the valves adnd when i putem back on i brok one of the covers.Now im still truckless.!!!!!!!!
     
  18. mudhog

    mudhog THEGAME Staff Member Super Moderator

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    but at least you found the problem /forums/images/icons/smile.gif
     

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