Sick Mercruiser V8

[mnypitboat]

Re: Sick Mercruiser V8

Ayuh,... Sounds like they went Lean,+ detonated to death...

Origionaly this all started when we ran low on fuel. I suspected at the time that we had sucked up some water from the bottom of the tank, now I am fairly certain. I had hoped that there was no permanent damage, but after a couple months of chasing the noise then it getting worse and worse, I figured on a rebuild or replacement. So that is where we are now.

 

[mnypitboat]

Re: Sick Mercruiser V8

OK engine is back in the boat. Now to get it all wired back up and test fired. Taking a rest, it is hot as hell out there!!

 

[John_S]

Re: Sick Mercruiser V8

I just read through your thread. Up to about 3/4 of the way through, I was thinking calapsed or sticking lifter, I then came upon you having that same thought. But, it is not clear that anything more than running a cleaner and a general visual inspection of valve train was done. Did you end up just getting a new set of lifters, or was a more detailed inspection (especially the one to the bad valve) performed?

 

[mnypitboat]

Re: Sick Mercruiser V8

I just read through your thread. Up to about 3/4 of the way through, I was thinking calapsed or sticking lifter, I then came upon you having that same thought. But, it is not clear that anything more than running a cleaner and a general visual inspection of valve train was done. Did you end up just getting a new set of lifters, or was a more detailed inspection (especially the one to the bad valve) performed?

Yeah it turned out to be a cracked valve. I guess its called "tuliping". Same thing on the new engine I bought, same valve same cylinder. The tops of both 4 and 6 pistons were pitted and damaged, so I ended up getting a rebuilt bottom end and a set of remaned heads. Its back together and in the boat, just bolting things back up and wiring it all up. Should have it running later tonight.

 

[mnypitboat]

Re: Sick Mercruiser V8

Oh and a blown headgasket between 4 and 6.

 

[John_S]

Re: Sick Mercruiser V8

so I ended up getting a rebuilt bottom end and a set of remaned heads.

OK, I missed that part. I thought you went back to just fixing the original engine. I hope the start-up goes well.

 

[carcraze]

Re: Sick Mercruiser V8

Any idea of the cause of the valve tuliping?

Engine was lugged down, detonation, age?

Just curious for my own knowledge.

 

[mnypitboat]

Re: Sick Mercruiser V8

Any idea of the cause of the valve tuliping?

Engine was lugged down, detonation, age?

Just curious for my own knowledge.

I ran it hard for a long period of time, then it started pinging. I origionally thought I sucked up some water from the bottom of the tank, but it appears that it had a blown headgasket between 4 and 6, and I think the compression was leaking back and forth. I have to guess that is what caused it. Probably from running it hard while it was leaking and detonating.

 

[mnypitboat]

Re: Sick Mercruiser V8

So newest news. I got it all wired up and test fired. I couldnt get the outdrive back in. Since we were going away for the weekend, I just brought it in to the marina to have it finished. They called me Saturday and told me the gimbal bearing was seized and that is why I couldnt get it back in. OK so they replaced it, replaced the impeller in the drive and remounted it. I also had them adjust the valves since I never got to do the final adjustment. They found a leaky drain **** in my starboard manifold and somehow my crank pulley got bent during this whole process.

So we got home today to rain and heavy thunderstorms, so no test drive. Hopefully we will get it in the water tomorrow or Tuesday. I put all the upholstery back in today, mounted my new bimini top, put a new negative battery cable to the starter and its ready to go. I am really looking forward to the trial run.