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

Preaching the Hot Rod Gospel according to the 4-stroke apostles:

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