1976 20R tuning help

Discussion in 'Maintenance/Repair' started by cocoabrew69, Aug 27, 2016.

  1. cocoabrew69

    cocoabrew69 Newbie

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    Hello!

    I have a relatively new to me 1976 Chinook with the 20R

    I have been going through it head to toe for the past month or so getting it ready for a cross country run.

    Things done so far:
    rear brakes, cylinders, wheel bearings, dif. fluid
    new tires, shocks, alignment
    rad flush, thermostat, oil change, etc

    so at some point one of the previous owners had installed an aftermarket fuel pump in the engine bay instead of replacing the in-tank pump when it failed.

    dropped the tank and installed a new in-tank pump because i was having some seemingly fuel related issues and the aftermarket pump was getting very loud and sketchy.

    cleaned the tank, new pump, new fuel lines, still having some issues, so i decide to clean the carb by spraying cleaner in the fuel bowl vent etc...
    now it seems to be running worse than ever heres whats happening...

    fires up no problem on absolutely COLD start after activating the choke by depressing the gas pedal.
    idles fine after warming up but is extremely LURCHY all the way through each gear.

    fires up fine after stopping for 5 minutes or so BUT after about 15-20 minutes to an hour it becomes much more difficult to start lots of turning over and pumping the gas pedal then when it finally starts its very sputtery and lurchy.

    trying to figure out where to start getting the lurch-ness out of the low end and why the WARM starts are so much harder than the HOT/COLD starts

    will post some photos of the engine ETC !

    Thanks in advance for any advice! :)
     
  2. jetas

    jetas Grand Toyotaholic

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    Did you change out the fuel filter?

    Does the choke stay fully open when warm?
     
  3. cocoabrew69

    cocoabrew69 Newbie

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    yep new fuel strainer at the pump and had a new filter in the engine bay before replacing the pump.
    (haven't got one in the engine bay as of yet getting a new one today)
    looks like the choke was staying fully open when warm. when i had the intake cover off to spray the carb it was vertical while running.
     
  4. cocoabrew69

    cocoabrew69 Newbie

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    noticed the distributor is all the way retarded (or advanced?) will be looking into that today.
    could that cause these symptoms?
     

    Attached Files:

  5. Frinzo

    Frinzo Toyotaholic

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    Have you replace any of the ignition system; i.e - spark plugs, cap, rotor, spark plug wires? If anything clean the spark plugs.

    Is the coil original?

    I would deffently reset the distibutor, it shouldn't be that way.
     

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