Page 1 of 1

Carburetor rebuild question?

Posted: Thu Nov 27, 2008 4:41 am
by Wayne64
Since I need to stay out of the way on this Turkey day I figured the shop was a good place to be. With the M37B1 I also got an extra original carb that I thought to take down and get a feel for the B&B. The one snag so far is that the accelerator pump piston is stuck in the upper cover bore. I've soaked it good with PB Blaster and did some real light tapping but it hasn't budged. Are there any tricks for removal?

Posted: Thu Nov 27, 2008 9:12 am
by Carter
Most likely the leather cup and the metal carb body have corroded and are fused together. The piston will be so damaged that no amount of care will allow it to be used again. I have had success removing the piston working a very small thin blade knife around the pistons bore and then allowing all to soak in solvent then twisting the piston to free it. This wrecks the leather cup but will allow the pump plunger to be removed.

Posted: Thu Nov 27, 2008 9:29 am
by Wayne64
I should have explained it better. The leather cup end came right out of the bodies bore. The other end which is the vacuum piston end is stuck in the top cover. I may try 125 psi or a bit of heat from my heat gun?

Posted: Thu Nov 27, 2008 7:27 pm
by MSeriesRebuild
I've seen a few pistons stuck, more likely is the retainer that holds it in place. A little gentle tugging usually does the trick.