The Stovebolt Site Forums The Shop Area Engine Shop 235 has no power now

Hi Everyone,
Today I fired up the 235 in my 1962 chevy pickup, and she ran ok. After I timed the engine, she idled great. Then I took the truck for a spin, I was disapointed.
In first gear she's fine, but when I shift into second + third she's real slooowwww. :mad:

At the one end of the vacumm advance, there is a nut that comes off, then the spring comes out. This spring is VERY stiff, could I replace this spring with a slightly less tensioned spring?

The replacement vacum advance holds vacum, but the old one doesn't, could the spring be the wrong one? The distributor moves back + forth by hand, but not with the engine running.

I'm almost about to go pull the replacement one back out, putting the old wornout one back in.
Any help would be greatly appreciated.
David

You're not supposed to take the 235 vacuum advance units apart. When you revv the motor in neutral, the dist should rotate a little as the vacuum advance works when the motor is revved up. Make sure you're getting vacuum at the distributor. Some vac advances are supposed to be hooked to manifold vac, others to ported vac that only gets vacuum above idle.

The lower part of the vacuum advance bolts to engine block. The distributor is clamped into the upper part of the vac advance unit. If the clamp holding the dist is too loose, or if the vac advance unit is somehow binding, it won't work correctly.

Check timing. You should have 10 degrees or so BTDC at idle with vac advance disconnected. With vac advance connected, you should have not more than 38 degrees total timing at 3,000 RPM. Check for stuck mechanical advance weights or springs in distributor, along with stuck vac advance.

Did you use an O-ring or something? Every 235 distributor Ive ever seen had no O-ring or gasket. There is nothing supposed to be in those grooves along the dist body where it slides into block.

good luck

chip