I'm replacing Rings and want to remove the pistons from the rods without splitting the case.

Are these wrist Pins suppose to be Butt Hole Tight
It's like it will take a Freaking Press to remove them

What's the trick to these little bitches that don't want to move
Oh Yea, the clips are rmoved

Thats a delicate way to put it

I think they all are slip fit, I would brace the rod and tap on the pin after soaking the "butthole" with penetrating oil

Warm the piston with a propane torch and they should tap out fairly easy.

Piece of 1/2 PVC pipe and a hammer, IIRC

Like butter!

Ouch, no hammers, ever!! We're not building a deck! Think of what it's doing to the rod and rod bearing. Besides, I don't think you can drive #1 & #3 out they're to close to the flywheel flange.

How about a piston pin puller? We use them everyday to remove snowmobile piston pins.
Click to view attachment

How does it work & where do you get one?

"Ouch, no hammers, ever!! We're not building a deck! Think of what it's doing to the rod and rod bearing. "

I thought the same thing while watching Jake Raby's engine build video.
He tapped them in with a mallet and I thought the same thing " what it's doing to the rod and rod bearing. "

I meant that the hammer is used to tap the pvc. The pvc is soft enough not to scar any metal that it comes in contact with.

"The pvc is soft enough not to scar any metal that it comes in contact with"

What we are questioning is that - when you hit the end of the side of the rod with anything, it is applying a torque to the rod and rod bearing that it was not designed to handle.

So taking apart an engine is acceptable using this method IF you plan on replacing the rod bearings.

Assembly is a different matter and you need to be very careful.

Stu

I use a slide hammer and a 10mm T1 head stud with a 15mm wrench size nut on the end. You can't push one of the pins out because it hits the case flange where the tranny bolts up. I see no reason why you can't do that, and it's my opinion you're not gonna hurt the rod bearing. If you're worried about that, have a strong friend hold the piston while you extract the pin. I generally pull the rods anyway, checking them for size and adherence to specs, and replace the wrist pin bushings. New rod bearings are a part of that process.

The Cap'n

I use an electric heat gun and just warm up the pistons slighty and they push right out.

Jsaum

[quote name='rdauenhauer' date='Jan 12 2012, 11:39 AM' post='1603611']
[quote name='hasaramat' post='1603593' date='Jan 12 2012, 09:48 AM']
How about a piston pin puller? We use them everyday to remove snowmobile piston pins.
Click to view attachment
[/quote]

How does it work & where do you get one?

It is a great tool. You extend the inner shaft all the way out and remove the two small nuts on the end of the shaft, they are reverse thread so when you use the tool they do not loosen up. Then you put the inner shaft through the piston pin and put the nuts back on the end. The brass housing is hollow, as you back out the big side of the inner shaft it pulls the piston pin into the brass housing. The brass housing has a nice curve on it to support the piston. There is absolutely no pressure put on the rod at all. It will pull the toughest pins out of most pistons. I added a couple more pics of another pin puller.
Click to view attachment
Click to view attachment
Click to view attachment

Sorry, forgot about the where to get them. I get them from Western Power Sports. They have 3 or 4 different pullers in there book rangeing from 24.95 to the fancy anodized one for 70.00. They will pull pins up to 24mm, and you can modify them to pull bigger pins.

Well I’m pleased to tell you that I did get another Piston off tonight…. Heat is My Friend!!
76- I didn’t have ½ PVC so I used a ½ wooded dowel. I like the PVC ideal. I’m going to get some just to have around.

John – Not to worry.. I did not Hit the Pin like I was driving a nail in a deck. I tapped lightly on them, but not until I secured the Piston so it would not put any impact on the Rod. Oh Yea, Heat is my friend

Wish I had one of those tools !!! Would make things a lot easier.

Oh Yes, You can remove #1 pushing the Pin towards the flywheel flange. Don’t know about #3, That might be to tomorrow night if I get to work on her.