Question 1994 c3500 dually 7.4L timing help

Discussion in 'Classic GM' started by Lividtaco, Dec 19, 2016.

  1. Lividtaco

    Lividtaco New Member

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    Oct 7, 2016
    Ok so I have a 1994 crew cab c3500 long bed dually with the 7.4L 454 motor. Initial issue was ga's mileage dropped from 10ish when hauling to around 4-5. So went under hood to the severely under maintenance farm truck and ended up much deeper then I had envisioned.

    Like a moron when taking the distributer out so that I could replace the upper intake gasket I didn't make any marks what so ever because I didn't anticipating moving the engine at all. Needless to say after realising damper had some serious wear and deciding to change it, the time cover gasket, oil pan gasket etc, the motor has probably been turned by me or my farm hand. Neither of us did any adjustments what so ever to the timing chain or gears. After getting it all back together, finding TDC and getting rotor to face #1 cylinder I tried to start the truck and it wouldn't turn over (only tried once, key turned maybe 3 seconds). Upon inspection I forgot to plug in the 4 pin connector on back of distributer as well as the 2nd plug going to the (igniter block??) Hoping that's not a huge messup... corrected and tried again and per my understanding of this timing light the light flashed then the injectors would shoot gas and when let off the ignition it was like there was a backfire in the throttle body where compressed air /ga's came backwards through the throttle body. I've only tried to start it those 2 times. So first couple questions (I'm hands on/visual learner all this reading trying to figure it out not working so well thus far)

    When they say line up rotor to cylinder 1 at TDC, does that mean line up the rotor to cylinder 1 spark plug cable on the distributer cap or physically facing cylinder 1?

    As far as wire order on the cap goes is there a set position for each wire or as long as I have it in the correct fire order and rotor facing correct wire to start that should suffice?

    When rotating the motor manually does that 4pin connector need to be unplugged even if battery is disconnected?

    I guess I just need clarity on the smaller details. From what I understand it seems like I'm 180° off and pulling the distributer out rotating the shaft only 180 and dropping it right back in should clear up the issue? Do /should I reset to TDC yet again before doing this or since timing wasn't an issue before I should be OK doing it where it lies?

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