TH350 RPM Drop when put in gear

Discussion in 'Transmission & Driveline Topics' started by BP80Z28, Jul 6, 2017.

  1. BP80Z28

    BP80Z28 Veteran Member Lifetime Gold Member

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    Hi th350 when put in gear the rpm's drop to almost stall. What should I be looking for.
    Thanks
     
  2. budro6968

    budro6968 Veteran Member

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    Check timing and raise curb idle to spec. Set parking brake and chock wheels first.
     
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  3. cadillac_al

    cadillac_al Veteran Member

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    In my experience it is usually a big vacuum leak. It should slide into gear with very little idle drop.
     
  4. CorkyE

    CorkyE Veteran Member Lifetime Gold Member

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    With a stock torque converter, you'll have a bit of a drop, but not like you're describing. Those are two good posts above, I would start first looking for a vacuum leak. If you have a leak, you'll never get the carburetor adjusted. I like to use an unlit propane torch to check for vacuum leaks, there are other methods. After leak test/repair, verify the timing is correct, then move to adjusting the carburetor.
     
  5. budro6968

    budro6968 Veteran Member

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    My buddy was trying to do the curb idle on his ford F100, He was inside the engine bay to adjust. He blipped the throttle and ran the truck into the wall with him in the bay. His wife could not wait to tell me that one. This is a guy I have known for years
     
  6. 70-camaro

    70-camaro Veteran Member

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    Are you running vacuum advance? If so ported or manifold vacuum? When I tried to run full manifold vacuum mine would not idle in gear either. Switched to ported and no problems.
     
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