Questions and Answers If you have general RC questions or answers discuss it here.

OS FS 61 help

Reply

Old 06-04-2014, 06:04 AM
  #1  
skylane42
Thread Starter
My Feedback: (53)
 
Join Date: Apr 2002
Location: Portage, MI
Posts: 577
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default OS FS 61 help

I have a 20 year old OS SF 61 2 stroke that I got from a guy who said it has been sitting for that long. He did run the motor a few times in a Aeromaster. The motor is pretty much locked up. I started tearing it down. One of the problems I am having is I can not get the con rod out to pull the piston. I have the sleeve out. The wrist pin is frozen so I can not slide the conrod out far enough to clear the crank. Is there a proper position the conrod needs to be in for disassembly? I have tried at the top and what looks like a recess at about 4 o`clock in the crank. Right now I have the piston wrist pin and piston soaking in WD-40.

Also I tried to slide the sleeve back in and just binds. Does the case need to be heated to re-install the sleeve?
skylane42 is offline  
Reply With Quote
Old 06-05-2014, 07:19 AM
  #2  
Bax
My Feedback: (11)
 
Join Date: Apr 2002
Location: Monticello, IL
Posts: 19,482
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

First off, you'll likely need to heat the piston/wristpin/rod assembly to soften any cooked-on fuel residue. You probably have a lot of fuel residue cooked onto the wristpin so that the conrod won't slide to one side, Once you can get the rod all the way to one side of the piston, then you can remove the rod from the crankpin. Even so, you may need to pry the lower rod end off of the crankpin. Use the head of a large carriage bolt as your lever. Works very well.

The ring groove in the piston has a pin that is used to prevent the ring from moving. The ring gap goes there. If the ring isn't lined up so that the ring gap is at the pin in the ring groove, the cylinder liner won't slide down. If you look at the top of the piston, you should see something that looks like a dot. It will be located towards the rear of the engine on the side away from the exhaust port...on about a 45-degree angle from the center of the piston with reference to the engine's fore-and-aft centerline.
Bax is offline  
Reply With Quote
Old 06-05-2014, 07:27 AM
  #3  
skylane42
Thread Starter
My Feedback: (53)
 
Join Date: Apr 2002
Location: Portage, MI
Posts: 577
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Well, I broke the bottom of the piston trying to get it to rock.. it is a ABC motor. I think with all the rust on the bearing etc I will just sell off what good parts are left. Thanks for the advise.
skylane42 is offline  
Reply With Quote

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service