I have chronic stuck #4 exhaust valve issues in my '76 Tartan 30.
At Don's advice, I've been running MM oil in the tank, and last year, at his advice, I reamed the exhaust valve guides 0.317" to increase clearance a bit. But the problem persists. Don and I corresponded recently, and he suggested that I post the matter here and see what we learn.
Don's theory is that the Tartan 30's port side thru-hull exhaust exit somehow lets moisture back into the exhaust manifold which, in turn, accelerates rusting of the exhaust valves, the stems of which are, of course, are open to the exhaust manifold. Since the manifold exhaust flange is at the rear of the engine, the #4 exhaust valve gets the moisture.
Does this ring true to other Tartan 30 (or Tartan 34)owners, or other boat owners with side-exiting exhausts?
FYI - the exhaust exits the manifold via the rear of the engine, which points toward the bow, runs through a 12"-15" 1 1/2" exhaust pipe to the waterlift muffler, then through a vented loop and out through a thru-hull on the port side, just at the waterline.
What fixes are there? Any suggestions?
Thanks,
John Feingold
Tarte Tatin
Tartan 30 #430
At Don's advice, I've been running MM oil in the tank, and last year, at his advice, I reamed the exhaust valve guides 0.317" to increase clearance a bit. But the problem persists. Don and I corresponded recently, and he suggested that I post the matter here and see what we learn.
Don's theory is that the Tartan 30's port side thru-hull exhaust exit somehow lets moisture back into the exhaust manifold which, in turn, accelerates rusting of the exhaust valves, the stems of which are, of course, are open to the exhaust manifold. Since the manifold exhaust flange is at the rear of the engine, the #4 exhaust valve gets the moisture.
Does this ring true to other Tartan 30 (or Tartan 34)owners, or other boat owners with side-exiting exhausts?
FYI - the exhaust exits the manifold via the rear of the engine, which points toward the bow, runs through a 12"-15" 1 1/2" exhaust pipe to the waterlift muffler, then through a vented loop and out through a thru-hull on the port side, just at the waterline.
What fixes are there? Any suggestions?
Thanks,
John Feingold
Tarte Tatin
Tartan 30 #430
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