How fast can a valve seal fail?

[Chas H]

I have seen the valve guide come loose in the head.

[Blue 72 250]

Thanks for the input.

So to check the valve seals I would remove rocker and compress the valve spring right?

The manual that I have only describes the removal of the head and I am not sure of the procedure. Please advise.

Originally Posted by Chas H

I have seen the valve guide come loose in the head.

Yup, and that will trash a head in short order.

I used a vacuum guage to help diagnose the problem, the guage needle fluttered violently, on the 190SL. It didn't smoke a bit, but it had a very odd misfire.