merc rod bolt specs

[Jerry Beebe]

Hi,
I'm new to this site and hope I'm doing this right.
Can some one tell me the torque specs for a 60hp merc
rod bolt. This is the "cracked Rod" type not the bolt through and nut.

 

[AMD Rules]

Re: merc rod bolt specs

What year/serial # is that motor?

Typically, you'll find instructions like this:

"When connecting rods are attached, and bolts drawn down finger tight, torque rod-cap bolts to 15 lb. in. (1.7 N·m). Recheck alignment. Re-torque to 120 lb. in. + 1/4 Turn. Recheck top and center main alignment with dowel pins."

Yours may vary, depending on the year.

 

[Jerry Beebe]

Re: merc rod bolt specs

What year/serial # is that motor?

Typically, you'll find instructions like this:

"When connecting rods are attached, and bolts drawn down finger tight, torque rod-cap bolts to 15 lb. in. (1.7 N·m). Recheck alignment. Re-torque to 120 lb. in. + 1/4 Turn. Recheck top and center main alignment with dowel pins."

Yours may vary, depending on the year.

I think it is an 88........sn OB343140. It has the cracked rods with the tapped holes instead of the thru bolts. The clymer book says 15 inch and then 30 foot lbs. I couldn't find anything on 60hp motor. Someone told me the 60-70 and 90 was the same block. your thoughts?

 

[AMD Rules]

Re: merc rod bolt specs

That is an '88 motor. I have a manual for it, but my neighbor borrowed it. Specs written above are for a newer motor (OG5... ) but I suspect they are the same.

The 50/60/70 blocks were the same in '88. The 75/90 were a bit different. They may use the same conrods though.

30 ft-lb seems like a lot, for such small bolts. Perhaps that extra "1/4 turn" after 10 ft-lb equates to a final 30 ft-lb.

 

[Jerry Beebe]

Re: merc rod bolt specs

Thanks for the info. This is our first outboard overhaul and I hope it works out. My brother in law is helping me and he used to be a gm mechanic so we aren't totaly in the dark. There are a lot of differences between automotive and two strokes. Again.................Thanks
Jerry