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Broken motor mount?

I have a 1976 F-250, I have been working on it for a few months and it’s coming along nicely. It has a 360, and a c-6 tranny. Today I used it to haul some wood from the lower part of my property, I notice the shifter lever moving by itself. It also began to have trouble running (it always had some problems with stumbling) when It was on the uneven ground. (flattish, but bumpy)Beings that the truck was not on flat ground, could a weak fuel pump be causing the stubling?

So two questions here actualy, 1) How can I tell if the mount is damaged (the shifter only movies when the truck is under stress) it can still be shifted and the linkege is not jammed or misaligned.

Cold it just be from the frame of the truck twisting on the uneven ground?

And 2) how can you tell if your fuel pump is weak.



All fuel pumps for carburetors are weak. It takes about 2 PSI to supply a carburetor. It could still be broken. If the shifter moves about an inch it is probably OK but if it moves four, be suspicious.

You can try changing that big ignition module that’s near the left hood hinge. Parts people will ask if it’s a blue grommet or black grommet module. The rubber grommet looks black when dirty, so you remove the module and turn it over. Usually, the bottom isn’t dirty and you won’t have to clean it to see the blue. They could sell for less than $20.

If the module is hot after running a while, it might be bad. The stumbling probably doesn’t happen when the engine is cold. Make sure the hot air pipe or tube is connected to the air cleaner housing. Check vacuum lines for cracks at the ends. When the rubber gets hard, the ends split.