Bolts on 40 H.P. crank

[nimmor]

Got a 1964 40 H.P. Johnson electrmatic that I am tearing apart. I have gotten down to the crank and the bolts holding the piston arms are funny star shaped. Does anybody know what you call the wrench used to remove these. I have seen sockets in this design but not for sure of the size either. I have a manual for this engine but it makes no referance to this.

 

[Joe Reeves]

Re: Bolts on 40 H.P. crank

A box wrench or socket will handle those bolts...... 5/16" 12 point.

When time permits, visit my store (copy/paste) at: stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store

 

[Evinrude Boater]

Re: Bolts on 40 H.P. crank

The piston arms are called connecting rods. The part bolted to the bottom is the rod cap. Are your bolts like a conventional hex head bolt but not a hexagonal shape. Some have allen head bolts where you need a bit to insert into the bolt head.
When you do get them off be sure to keep each rod cap with it's rod and in the same orientation. They are matched pairs.

 

[samo_ott]

Re: Bolts on 40 H.P. crank

and don't loose any of the bearing pins on the rods...

 

[F_R]

Re: Bolts on 40 H.P. crank

It takes a 5/16" 12 point socket. Those bolts are TIGHT! It takes a strong socket to break them free (and re-torque them when reassembling). In addition it requires a thin-wall socket. All of the above just about adds up to you gotta get a nice expensive Snap-On socket.