60hp mercury 1994 after rebuild tuning problem or other sugestion ?

[Devonaaron]

I rebuilt this motor to sell im just not a mercury guy very much at all I rebuilt the carbs the ignition has strong spark etc. This is the problem it hick ups and misses bad at low rpm dose it at higher RMP but not to bad. I just rebuilt with new pistons bearing etc. carbs were very gummed up im just unsure why its giving me such trouble. I set the idle about 1 1/3 out i feel like its set to rich and It feels to get worse and better as I play with it. Im just unsure why its acting the way it is. Its also giving me smoke from the midsection between the block and power head so that could be a contributor as well im just not sure I installed the gasket but I had some problem getting the block on without messing the gasket up so ima back track to that but can someone give me some insight on this motor I installed a 120 degree thermostat and am mixing it 1:25 but im breaking this motor in and with this modern ignition it should be able burn off the oil and prevent fouling. If theirs any mercury people that would like to help me out a bit im all ears.

 

[Faztbullet]

Re: 60hp mercury 1994 after rebuild tuning problem or other sugestion ?

When you say "rebuilt" what was done exactly and why???

 

[Devonaaron]

Re: 60hp mercury 1994 after rebuild tuning problem or other sugestion ?

When you say "rebuilt" what was done exactly and why???

It had a sleeve that slid cause unknown but it was just rebuilt I could tell. So I had it resleeved all 3 cylinders and had bored .20 with new .20 over pistons. New bearings for the rods and wrist bearings. This is a premixed motor as of now and it was that way since I got it but it was an oil injected motor. I fix outboards as a hobby but mostly the johnsonruds never really a mercury fan I think there junk and if I were to ever get one it would be a v6 about a 95 they are very good motors besides the electronic problems.

 

[Faztbullet]

Re: 60hp mercury 1994 after rebuild tuning problem or other sugestion ?

The sleeves slip due to overheat and loose fit from factory, I pin them in place. Make sure the check valve are behind the reed plate as these can fall out easily and cause all kind of running problems...(#7 & 8 in link)

http://www.boats.net/parts/search/M...302PD/CYLINDER BLOCK AND CRANKCASE/parts.html

 

[Devonaaron]

Re: 60hp mercury 1994 after rebuild tuning problem or other sugestion ?

I checked the reeds before put it together it is running slot better now but still coughing I ran it for awhile today and it gets better a slight bit as it warms up but still not good at all and it's not souring back out the carba so not sure if reeds are to blame

 

[Faztbullet]

Re: 60hp mercury 1994 after rebuild tuning problem or other sugestion ?

Didnt say reeds ,check valves.....

 

[Devonaaron]

Re: 60hp mercury 1994 after rebuild tuning problem or other sugestion ?

What is the use of the check valve on this mercury. Also when I prime the motor it smoths out a bit. Any ideas

 

[Devonaaron]

Re: 60hp mercury 1994 after rebuild tuning problem or other sugestion ?

Didnt say reeds ,check valves.....

Im thinking more and more about this and I think your right, I also here a clicking every revolution its not laud but when you work with outboards almost every week you know when somethings not right and its not something vibrating to my knowledge could it be that check valve

 

[Devonaaron]

Re: 60hp mercury 1994 after rebuild tuning problem or other sugestion ?

What is the purpose if the check valve whats is it's function

 

[Faztbullet]

Re: 60hp mercury 1994 after rebuild tuning problem or other sugestion ?

It the recirc check valve that keeps cylinder from loadind up at idle. If they are missing motor can load up and foul plug causing a miss. The clicking can be from trash in the upper/center bearing or a broken ring hitting a port.

 

[Devonaaron]

Re: 60hp mercury 1994 after rebuild tuning problem or other sugestion ?

That's scary as far as the clicking goes. Due to the fact I replaced rod bearings and cleaned and greased the main crank bearings as well. As for broken rings i don't think that's the case ether it has new pistons and new sleeves. What do you think I should do ?