[aggressivebuggy]

My brother in law and I both have 19sx Mariah's with 4.3L Mercruisers. His is an "05 I believe and mine is 1 year newer. Both are typically stored outside in a moderate climate although I got lucky and somebody offered to store mine in the heated garage this year My bro in law drained the engine with the two blue plugs at the end of the fall last year. This year he started the boat up once temperatures were pretty steady in the 70's to 80's. The second time he started it up with a hose (with that plunger thingy) running into the fins and realized the exhaust manifold was leaving on the driver side. Something fearce too. He didn't notice this the week before when he started it. Well after the shop tore it down and replaced it (it was cracked) and started the boat the other side started to leak. So now he's got two manifolds cracked.

Does anybody have any ideas as to why? Is there another way he should be draining the engine for the winter? Is there something else that could have caused it? Has Mariah addressed a situation with it? Should I be expecting the same problem?

[mikeyt]

Sounds like someone forgot to drain the manifolds too. A cracked manifold is usually a sign of improper winterization.

[WetWilly]

Hi aggressivebuggy,

Sorry to hear about your brother's manifold.

I agree with Mikey, sounds like motor wasn't drained properly. There are two sets of drain plugs, one on the block and another at the exhaust manifolds (I believe they're on the exhaust manifold water inlet elbows) and Mercruiser recommends removing the hose from the thermostat housing to the engine water pump to insure all the water is drained from the top end of the motor.

WetWilly

[aggressivebuggy]

I believe that's where we missed a key element. Neither of us were aware of the drain in the elbow or the need to take the tube off. But it makes sence. Its the coldest winter we've had and my was saved because of warm storage.