'77 K5 carb and timing problem

Discussion in 'The Garage' started by rattlesnake, Apr 12, 2004.

  1. rattlesnake

    rattlesnake Newbie

    Apr 4, 2003
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    Milford, Kansas
    \'77 K5 carb and timing problem

    does any one have any information on adjusting the timing and carb to start my truck? I just finished rebuilding the engine and carb, now it won't start. I have checked and re-checked every thing I could think of. I have a '79 350 and an eddlebrock 650 installed. Please help if you can. /forums/images/graemlins/confused.gif
  2. v-3500

    v-3500 Registered Member

    Apr 3, 2004
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    Re: \'77 K5 carb and timing problem

    First, you need to make sure you installed your distributor correctly...

    1. Remove the number 1 cylinder spark plug.

    2. Place your thumb over the spark plug hole.

    3. Crank the engine until the compression stroke blows on your thumb.

    4. Place a socket on the harmonic damper bolt, and line up the timing mark on the harmonic damper with the timing chain cover timing tab '0' mark.

    4. Install distributor with the Rotor pointing at the number one spark plug wire.

    5. Install distributor cap.

    6. Connect spark plug wires 1-8-4-3-6-5-7-2 clockwise on the distributor cap.

    Second you need to adjust your carburetor. To adjust idle mixture screws in the ballpark range:

    For Carter style or Q-jet carburetors: Screw the idle mixture screws in, until they seat. Then, back out the idle mixture screws two turns.

    For Holley carburetors: Screw the idle mixture screws out, until they stop. Then, screw the idle mixture screws back in two turns.

    To adjust electric choke on carburetor: loosen the three screws holding the plastic choke cover. Turn until choke flap has 1/16 to 1/4 of inch gap between choke flap and carburetor intake throat.

    Third, you need to make sure the valves are adjusted correctly. I personally do not like the factory method. The way I do it is:

    1. Put each valve on the lowest part of its lobe center one at a time.

    2. With your fingers rotating the push rod, tighten down valve rocker arm just until the push rod stops rotating.

    3. Turn rocker arm adjusting nut only 1/4 turn more. (Not the 3/4 the factory recommends)

    4. do a running valve adjustment later.

    Forth, you may also need to prime the carburetor with gas (not starting fluid) to do the initial start up.

    If you keep having problems starting your engine, after doing what I have instructed, you may want to make sure your timing-chain is set correctly.

    Many times (I have done this myself) when people buy the trick double roller timing chains, which have three different settings Advanced, Standard, and Retarded, they use the incorrect camshaft gear timing mark.

    Make sure you use the timing marks on the outer edge (close to the teeth) of the camshaft gear, and not the similar marks located at the center of the camshaft gear.

  3. justhorsinaround

    justhorsinaround 3/4 ton status

    Sep 16, 2003
    Likes Received:
    Northerish Phoenix, Az
    Re: \'77 K5 carb and timing problem

    Well hell. I was thinkin about helpin ya out but I can't add anythin. Even on the pushrod adjustment. Well ummm....

    Good luck to y'all in the future.


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