2 bad engines

[caverun man]

I know im not in the right thread but cant get in the mercuiser thread. I have thrown a rod thought two engines. The first was a 2002 Rinker with a 96 hours . The engine is a 5.7 300 hp brovo 3. That time my top blowed back so I pulled back on the gas real quick and bang rod thought the block. This time it was the same motor size in a 250 Rinker Cabin cuisers with 390 hours but this time i had to go out of forward to revese real quickly to avoid another boat come at me. No damage to the outdrive but a rod out the oil pan. Would going from forward to revese quickly blow a engine.

 

[Cricket Too]

Re: 2 bad engines

Don't see why going from forward to reverese would do anything to your block, it continues rotating in the same direction, unless you gunned it real hard in reverse, and it was about to blow a rod anyway, and it would have done it in forward just as easy....maybe just a coincidence.

Get a a good outboard and be done with it.

 

[Silvertip]

Re: 2 bad engines

The fact that you chopped the throttle real quick from fairly high speed (twice) says you are inhaling water throught the exhaust and hydrolocking the engine. To toss a rod once at low hours is a fluke -- to do it twice, on different boats, points to operator error and I don't mean any disrespect when I say that. Valve overlap can get hairy on higher HP engines which is why you really need to select camshafts carefully during rebuilds or when doing performance upgrades. Just a hunch on my part.