New Motor Break in question...

kaydano

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Does a new inboard engine need special break in? A friend is looking at a used boat where the guy didn't winterize it, it cracked, and he had a new motor put in. The work was done by a reputable shop, but given the guy is obviously an idiot, or lazy, I'm guessing if there's a break in procedure on the new one, I'm doubtful he followed it right.

But, if no break in is needed, this might be a good boat. 8 years old. 50 hours on the new motor. Mariah brand ski boat.

Can anyone help?
 
If there's more than 10 hours on the new motor it's way too late . . . it's broken in by now, good or bad.
 
I know, I was trying to figure out whether it mattered or not.

If inboards don't need a proper break in, then there's no risk in buying the boat.

Still looking for others thoughts....
 
With only 50 hours, I would buy it.
 
Even if it wasn't broken in properly?

The question I'm basically asking is whether an inboard needs a break-in.
 
The only thing I was told on my Merc I/O was to not run wide open for more than 5 minutes for the first 10 hours and just vary the RPM range. After that I was good to go. I don’t think my manual had a specific break in procedure.
 
I believe all engines need a break in to some degree, inboard, outboard, I/O, it shouldn't matter. It's probably less important now than in the past with all of the high tech and modern lubricants and such. From my understanding, even if it was broken in poorly, all that means is at best it will "like" one particular rpm range, at worst the rings will not have seated properly. For the latter you'll notice the oil getting dirty faster and maybe even have the oil level INCREASE as you use it. If you're worried, have a mechanic do a pre-inspection with a compression test.
 
Yes they should have one before you start hammering it. A compression test is the best bet for now. How is the current oil condition/level? Check plug condition. Do you know that shop? Can you test run before buy?
 
Agree with the compression test. That's what happened when we bought our boat. The people who owned it didn't winterize it and the block cracked. They had a new engine installed and then that's when we came in and bought a 4 yr old boat with a brand new I/O. We were told to not go WOT for at least the first 10 hrs. and to not stay at any one speed for any length of time. That's it. We changed the oil after the first 10 hrs. also.....
 
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