Re: Older mercury 115 rebuild
I usually do my own work, but I have a Merc friend that is a total wizard with Tower of Power Mercs. I have the short shaft case middle painted and back over there, and the PT+T ready. My motor will be a solid black wrap, newer style face plate...couple silver stripes for looks.. good looking now just sitting here in the shop!
On the motor, heres whats being done...
.."The powerhead I am building for you was originally a '72 1150.
The '72 1150 is a choked down 1350 with a few flow restrictions to give the lower HP rating so Merc wouldn't have to come up with a different powerhead to fill that HP range for the consumer market.
Initially this 1150 needed a rebuild because the inner water jacket had cracked and let water into #3 which was trying to die when I rescued the beast. It still had 95 psi on #3, but the rings had started to seize and consequently had scored the bore.
I had #3 bored .015 and installed a new piston there.
I had all holes pro-honed while I was at it and mic'd for roundness, etc to insure the beast was still within factory tolerences.
The block surfaces were machined too to insure everything was flat in the water jacket areas for a correct sealing.
All other pistons were carefully inspected, mic'd, & cleaned. I replaced one standard size piston too, but (4) of the (6) original pistons went back into their original holes.
Everybody got brand new rings & needle bearings.
The crankshaft got new main bearings.
The end caps got new seals & so did the crankcase.
I installed 1500 reed blocks and reeds, which meausre out the same as the original 1350 reeds.
I am installing '73 1400 carburetors - which are virtually identical to the original 1350 carbs & I am installing the original .0785main jets required for the 1350 at sea level
The exhaust tuner plate and inner water jacket are both NOS 1350 parts that I had machined to insure they too are flat so they will seal correctly.
These modifications: Main jets, reed blocks, tuner & inner wj complete the conversion of the 1150 to a true 1350.
The only difference between the 1350 and the 1400 blocks is the 1350 had an oval tuner to the mid-section and the 1400 had the dual square port tuner to the mid-section. And,...The inner wj & tuner plate configuration changed barely."
So when I can find somebody thats knows his stuff, its money well spent. Pick your friends well, and life is good. I'm in the process of getting wiring done on the boat, and couple months should get the hull wet. I'll do a post with pix in the Boat Building Forum when it comes together. Lots of work, but lots of fun too.