115 I4 Merc compatibility

[nofaultxx39]

my 99 115 Merc blew a hole in the side of the block. Three questions
1. What year short blocks are compatible with this (everything else is really good on this motor)

2. Can I use a 115 Merc saltwater powerhead or shortblock?

3. Are the 20" and 25" lower units etc interchangeable? (I see a fair amount of used 115 Salwater versions on ebay with complete motor but all with 25" shaft.

 

[CharlieB]

Re: 115 I4 Merc compatibility

Midsection length and lower unit shaft length are matched sets.

A LU from a 25 would need to swap the vertical shaft for a 20 before installation on the 20 mid, and so on.

Pwerheads should be interchangable.

 

[CharlieB]

Re: 115 I4 Merc compatibility

What went wrong to cause your failure?

I have a 96 and so far so good, what shouldn't I be doing?

 

[nofaultxx39]

Re: 115 I4 Merc compatibility

Charlie, do you have any idea what years might be interchangeable on shortblocks? My carbs, electronics, etc are all good.

Also what do they do different on Saltwater models?

As for the failure, I had it mounted on a 24' party barge used mostly by my kids. The lake we dock it at is fairly silty. We carry a wire with to open up the water discharge port if it stops. I know the overtemp and low oil alarms work. I was with on the boat when it blew. Sounded like we hit a stump.