4.3 Mercruiser Water in Cylinder

[hermannm]

Hello,

I was working on a friends boat this weekend and replaced the started. The engine ended up being hydrolocked. I pulled the sparkplugs and water came pouring out of the port side of the engine, all 3 cylinders. Would this be the exhaust manifold cracked? Is there anything else that it could be. What should the next steps be? Does the entire engine need to be taken out and rebuilt?

Thanks,


Matt

 

[JJJ]

Re: 4.3 Mercruiser Water in Cylinder

It could be the exhaust manifold/riser/gasket or as happened on my 4.3 a cracked head. Rust had plugged a small port in the head and it cracked the head.

How long was it hydrolocked? I lucked out, and blew it out (saltwater too) and lubed the heck out of the cylinders, changed the oil a few times after getting the water out and cranked it just to circulate the fresh oil, then just pulled the head and replaced it a couple of weeks later. I lucked out but worse case was I wasted a few hours and a gasket set. That was a few years ago.

 

[hermannm]

Re: 4.3 Mercruiser Water in Cylinder

It has been hydrolocked for close to 2 years. The water was pretty rusty that blew out of the cylinder when I cranked it over.

 

[joewithaboat]

Re: 4.3 Mercruiser Water in Cylinder

It has been hydrolocked for close to 2 years. The water was pretty rusty that blew out of the cylinder when I cranked it over.

If it has had water in the cylinders for 2 years you will need to tear the whole engine down. The cylinders will be badly rusted and pitted. The rings will be toast.
Keep us posted with some pictures.

 

[JJJ]

Re: 4.3 Mercruiser Water in Cylinder

yeah I'd say motor is pretty much toast at this point.