This may be an issue...

[jcupo6]

I was finally able to take the boat out with the newly purchased used 120hp Mercuiser out this weekend. It ran great in the driveway with no issues. Launched the boat and notice a slow drip from the exhaust manifold, was concerned but we decided to go anyway while keeping a close eye on it. Got her up to 27-28mph at around 3000rpm and noticed she was running a bit warm. The temp gauge was still green but was never that close to red before. Took the doghouse off and found this...





There are more videos if you if you look through my album. Looks like the PO sealed a crack in the bottom of the manifold with JB Weld or something, well it blew apart. Now there is some water in the oil, I am guessing/hoping the manifold explosion is the cause. I don't really have any questions, just thought I would share experience.

 

[Bondo]

Re: This may be an issue...

Ayuh,... My guess is, there was old freeze damage that was repaired...
Then,...
There was Freeze damage Again last winter...
That's what blew the epoxy out,+ Why there's now water in the oil...
It's Cracked in More places than it was last year...

 

[frank246]

Re: This may be an issue...

It prob. bursted on the inside also... letting water into the exhaust runner and into the comb. chamber.
If the exhaust frose, better check the engine to.

 

[JaseBosto]

Re: This may be an issue...

I smell a complete teardown....at least pull the head to be sure.

 

[jcupo6]

Re: This may be an issue...

Installed the new manifold, changed the oil, and fired her up. Ran for about 20 minutes and the oil did not turn, so I think we are good to go.

 

[Don S]

Re: This may be an issue...

Installed the new manifold, changed the oil, and fired her up. Ran for about 20 minutes and the oil did not turn, so I think we are good to go.

They seldom leak on muffs. Take it for a run where you get good temp and full flow from the raw water pump, and keep an eye on the oil..

 

[jcupo6]

Re: This may be an issue...

That's the plan! We are hoping to take her out tomorrow and run her pretty good on the Delaware Bay.

 

[Rocky_Road]

Re: This may be an issue...

Is that a rubber hose going to your carb in the very first picture?

If so...you might want to replace it with the only approved line between the fuel pump and the carb...steel. The 'water cops' will not let that fly.

Take a look at the picture, Don...and feel free to correct me if I am wrong!

 

[jcupo6]

Re: This may be an issue...

Is that a rubber hose going to your carb in the very first picture?

If so...you might want to replace it with the only approved line between the fuel pump and the carb...steel. The 'water cops' will not let that fly.

Take a look at the picture, Don...and feel free to correct me if I am wrong!

Hmmm, didn't know that was the case. You are correct, it is coast guard approved rubber hose. If I do in fact need steel line, I still have the steel fuel line from my old motor that I can swap out. Thanks for letting me know!

 

[jcupo6]

Re: This may be an issue...

Took the boat out yesterday, and it was almost perfect. The motor ran great, and the oil stayed perfect - no water in it at all. We ran the motor pretty good, went about 6 miles out in the Delaware Bay. On the way to the ramp, after about 5 hours of catching nothing, I noticed she was running hotter than she had been all day. The gauge crept closer and closer to the red so we shut down and let her cool for a while. Tried again and the gauge did the same thing, so we stopped. We were towed in by a sweet 50 foot fishing yacht. I am thinking, hoping, it's the outdrive impeller. I bought the drive new last September and was told it would be foolish to change the impeller until next season...

Here are some video's pre-overheating. Sorry for the crappy quality, it's hard to film and drive.