On Fri, 27 Jul 2007 10:44:27 -0400, "D.Smyth" wrote:

I have a 17 foot Doral with an older 4 cylinder Merc I/O. (Old
fashioned carburettor and distributor.)
It's been idling a little rough and stalling at slow speed. Today I hit
a wake fairly hard and the engine stalled.
I've changed the fuel filter and put the appropriate Wynn's stuff in
both the oil and the gas. Haven't had a chance to take it out again. Am
I on the right track or is it something more serious?
Any further input would be most welcome.
Tx
DS

Are the cylinders all making more than 100 psi compression
and within 10% of each other?
Is the ignition timing set correctly with a strobe?
Does an ignition tester show a strong spark?

Yes? Then the carb needs attention.
Float chamber needle valve leaking/sticking perhaps?

Brian Whatcott Altus OK