Reply To: ’54 Fleetwin – wont run on low speed

[Don]

Like others have said, perhaps someone took the friction block and spring out from under the twist grip handle…The mag plate might be sloppy, and/or coils improperly adjusted also…I would remove the plugs and recoil, then rotate the flywheel to see if the magnets are dragging on the coils…
I am trying to remember the whole story on this engine, did you pull the powerhead apart? If so, I’m sure you replaced the head gasket at that point. The plain head gasket with no ring should work just fine on this low compression engine….Did you notice any problems with the block or head mating surfaces that might cause a leak? Any signs of water in the cylinders, did the head gasket appeared burned through when you removed it? I would certainly use a new head gasket, reusing an old one is not advisable. Don’t try to “over torque” the head bolts in an effort to raise compression on the low cylinder. You will end up stripping the threads and warping the mating surfaces. I would not use a foot pound torque wrench either, use an inch pound set from 60-80 inch pounds. Once the engine has been run and cooled, by all means retorque the head bolts to this recommended spec.
I’m “guessing” your uneven compression is not due to a head gasket issue, but sure hope I am wrong…
The vibration at low speeds could be many things, perhaps you can post a video of the engine running. It is hard to know if the driveshaft shock absorber is an issue without disassembling the gearcase, which I don’t recommend right now. You don’t want to pull that apart for nothing. But, I would certainly drain and inspect the gear lube….Signs of water spell trouble which might include a shock absorber problem…
So, just want to understand…The carburetor idle passage core plug was missing, correct? Installing a new core plug improved the idle?