77 115 hp 1150 merc

[djstock1]

I ended last summer with a loud knocking from my motor at 3/4 throttle. I shut it off and got towed in after it cooled off, i started it up again and the knock was still there. I pulled the plugs and #3 had a bunch of whitish crud on it. ( melted alum?). I have taken everything off the power head to remove it form the rest of the motor, now I need to know how to get it off. I took the 6 nuts off the studs that appear to come thru to the lower unit, and 2 that appear to just go to the mounting bracket on the transom. What else she doesn't seem loose at all? I am now guessing the noise is a bearing on the camshaft?

thanks,
Don

 

[Chris1956]

Re: 77 115 hp 1150 merc

Don, That motor does not have a camshaft. All bearings are roller or needle. If you got all the bolts loose, push hard on the powerhead to break the gasket loose. There are two nuts in the front, and 3 or 4 on each side, just under the powerhead, under the lower cowl. All use a 9/16" wrench.

 

[Laddies]

Re: 77 115 hp 1150 merc

Did you get the 2 nuts on the very front corners of the drive shaft housing. I can guarantee that is is not the camshaft.

 

[djstock1]

Re: 77 115 hp 1150 merc

thank you for the reply, yes I got the 2 in the front also. I guess I need to put a little more force on it to break it loose.
thank you for the ref. manual pics where is this from. Looks like I need to get this manual so I can continue once I get the beast off. How much do you think it weighs?

 

[Laddies]

Re: 77 115 hp 1150 merc

Just a guess 95#

 

[djstock1]

Re: 77 115 hp 1150 merc

oops did not mean camshaft, Crank shaft or as you have said drive shaft problem or bearings on it.

 

[Chris1956]

Re: 77 115 hp 1150 merc

Powerhead is liftable by average guy. However, it cannot be removed easily w/o some help. Drop the gearcase first, as it will make install a lot easier. You need some help to get the powerhead to lift straight up for 6 or so inches to clear studs. I use a lousy block and tackle to do it.

 

[Vision91]

Re: 77 115 hp 1150 merc

watcha mean by an average guy can lift it off... im 5' 10 and 136lbs and lifted it off after i broke the gasket free. but yes a cherry picker is a lot easier that is if u have one. just messin with ya
@ DJ once u remove everything off the block it only weighs in around 100 maybe 120 at most

 

[djstock1]

Re: 77 115 hp 1150 merc

thank you everyone! I got her off and started pulling her apart. the lower main bearing is too worn but not causing the bind in the crank. when I pulled both end bearings off, I can now rotated the crank without obivious bind. but not smooth either, so when I have my next time available I will take the her down to the other bearings (those needle kind) and it is one or all of them and not a bent crankshaft....

 

[djstock1]

Re: 77 115 hp 1150 merc

taken all apart now, #2 piston scored badly and rings welded in groove so they are not free to seal in the cylinder. obviously will need to replace the piston. how do i repair the sleeve? The top of the cylinder does not seem to come off, to allow thru honing. What is the deal on the split bearings on the crank? I have never heard of those. It is obvious the only way they could be installed. Is this block beyond wisdom to repair?

thanks,
Don

 

[Laddies]

Re: 77 115 hp 1150 merc

If the cyl is not scored and you have a aluminum build up in the cyl which is the most common problem, wash the cyl with muriatic acid and a brush till the alumium is gone then hone it, if the cyl is scored you will have to find someone with a dead enf boring bar to bore it, there is no problem boring just 1 cyl as the pistons all weigh the same.