Removing pistons from rods

[Cadillac-ack-ack]

1962 40HP Evinrude Lark. Having difficulty driving the wrist pins out. I am getting the pistons pretty damn hot with a heat gun and attempting the "shouldered drift" method holding the piston between my legs and trying to drive the pin out from the "LOOSE" side. It might have moved a tiny bit but how hard is OK to hit it. The pistons are to be replaced but if assembly is just as difficult I'd be concerned with damaging new parts. Thanks - Pete

 

[F_R]

They really ought to be removed with an arbor press. Drive from the loose side. That means drive it all the way through the tight side. Yes, heat helps. Use the arbor press to install the new ones too. Slip the pin through the loose side, and into the supported tight side. If you don't have a press, take them to an automotive machine shop. They do that kind of stuff all the time.

 

[alldodge]

Agree, take it to a shop with a press and bring your new pistons. Cost is low and not worth messing up new pistons

 

[Scott Danforth]

Take it to a machine shop and $40 later the job is done

 

[Cadillac-ack-ack]

Seems to be unanimous, I'll be taking the job to a shop. Thanks, - Pete

 

[Joe Reeves]

Seems to be unanimous, I'll be taking the job to a shop. Thanks, - Pete

Yeah, that's really the way to go.

The underside of the piston... One side of the wrist pin has a "L" embossed on it (loose). I differ from F_R on this one, not to say that I am correct... BUT... I gripped the rod in a vice, heated the tight end with a propane torch, and beat the wrist pin out towards the loose end. Installing new pistons in the reverse manner could be touchy.

The machine shop would be the way to go.

 

[F_R]

Yeah Joe, you and I can sometimes get away with doing stuff like that because we have developed a "feel" for it. Sometimes the hard way after busting or bending something. Just for the record, here is what the book says. (It also says to use a piston cradle, which I've never owned one of)

 

[Joe Reeves]

Yeah Joe, you and I can sometimes get away with doing stuff like that because we have developed a "feel" for it. Sometimes the hard way after busting or bending something. Just for the record, here is what the book says. (It also says to use a piston cradle, which I've never owned one of)

Yeah F_R... I forgot about those and did use them if they were available. And yes, I did need to do a little retouching on the bottom of a piston skirt occasionally. No contradiction or offense intended towards your previous statement my friend.