Craftsman 3.7 Piston removal

[motorman1]

I've checked the search engine and can't find an answer, so can somebody here help me out? I'm trying my darnedest to remove the piston from this saw and can't find any evidence the piston has circlips. It appears to be just a pressed in style of wrist pin, if that's possible. Anyone have experience with this type?

 

[Guido Salvage]

Is it a Roper or Poulan built saw?

 

[motorman1]

poulan, looks exactly like a 3700, except it;s red

 

[Modifiedmark]

It is a press fit piston pin and there are no circlips, so you are correct there.

There is a special tool that was provided to press that pin out without damaging the piston. Needless to say that tool is more then likely obsolete.

I thought I had a picture of the one I made but can't find it. It is pictured and explained in the service manual. PM me if you want a copy of it.

 

[OhioGregg]

I've checked the search engine and can't find an answer, so can somebody here help me out? I'm trying my darnedest to remove the piston from this saw and can't find any evidence the piston has circlips. It appears to be just a pressed in style of wrist pin, if that's possible. Anyone have experience with this type?

Yes there is a tool for that. NLA unfortunately, unless you can find one on ebay or something. You can make one also. Just takes a little ingenuity I guess. Here is a pic of one to get some ideas from.

Gregg,

 

[RedFir Down]

Here is one.
http://www.weedeaterman.com/product_p/wem530031069.htm

 

[motorman1]

Thanks for all the help. You guys are great! Very relieved there are no circlips. I hoped my eyes were better than that. Will be trying the home made tool route. That tool is quite pricey for a one-time use.

 

[OhioGregg]

Thanks for all the help. You guys are great! Very relieved there are no circlips. I hoped my eyes were better than that. Will be trying the home made tool route. That tool is quite pricey for a one-time use.

LOL, I agree with the price! But if your a guy with CAD and you take a shine to them saws, It is a valuable tool to have. I bought mine quite some time ago, wasn't that steep.

Gregg,

 

[hotshot]

I've checked the search engine and can't find an answer, so can somebody here help me out? I'm trying my darnedest to remove the piston from this saw and can't find any evidence the piston has circlips. It appears to be just a pressed in style of wrist pin, if that's possible. Anyone have experience with this type?

Unless it's chewed up & has to be changed, I'd leave it alone.

Heat the piston crown (top) up to 250°F or more with a heat gun, it will easily press out then.
http://www.arboristsite.com/community/threads/poulan-thread.98495/page-1670#post-4983655

 

[Modifiedmark]

Randy, I think your confusing this with something else.

Heating the piston won't help. The pin is a press fit to the rod, not the piston. The rod is what has to be heated, but that is difficult to do with the piston in place.

In fact, after the pin has been pressed out of the rod when reinstalling, I heat the rod so the pin can be pushed back into the rod by hand.

 

[hotshot]

I swapped that piston out last fall 2014, & the process worked well for me.

I do remember putting that saw on its side & laying the heat gun on the floor to blow on the piston crown, but it probably would have been better & faster to blow it up under the skirt...sounds kinda kinky there huh?

You're correct, the con rod is the interference fit & the wrist pin rides on needle bearings pressed in the piston sides.

 

[motorman1]

I got the piston freed, thanks mucho! No circlips on this saw. Used the 10-24 threaded rod / socket method and it worked wonderfully for less than $3. Thank you! Will post later on the end results. You guys are the best!!!!!!