CannonFodder

My Feedback: (23)

I have an older OS 40 that I am trying to replace the bearings and its difficult to find information on this engine. I need to remove the propdriver from the shaft to ge the crank out and remove the bearings. Tha driver does not seem to have a key of any type I can see, I am thing I need to use a small puller but wanted to ask here before I try this.

Thanks in advance,

Mark

proptop

My Feedback: (8)

It sits on a tapered split collet...you'll need a puller and some heat. A small battery terminal puller will work.

One question...do you already have a new rear bearing?
IIRC those engines use an odd size (and difficult to find ) rear bearing.

big max 1935

My Feedback: (9)

OS has a puller just for their engines . Great planes # OSMG2548 ,$16.99 . Some other pullers chew up the washer & I just hate that ! Good luck, Max H.

proptop

My Feedback: (8)

Yes..most universal pullers have rather large and improperly shaped (for this application anyway ) jaws.

I modified the jaws of my puller w/ my Dremel by grinding a concave radius to match the radius of the driver...I also ground an angle on the back side or what would be the edge of the jaw that is closest to the cyl. when in use. (so the jaws can get deeper in the groove of the prop driver ) Also de-burred and smoothened them w/ 400 wet/dry paper and oil.

With the puller installed, and some pre-load applied, heat the prop driver w/ a heat gun or gently w/ a propane torch (low flame ) then a quick rap w/ a hammer on the puller screw should pop the prop driver off.


My modified puller will work on most engines...or at least all the engines I've needed it for so far anyway...

BTW, Max, I hate seeing tool marks, etc. etc. on engines too [:'(]
The O.S. puller might lessen that possability.

CannonFodder

My Feedback: (23)

Great, thanks for the advise. I thought that's what I was going to need. Appreciate the help!

And yes, I did find the bearing or at least that's what the online shop told me. They deal strictly in bearings for many types of engines, I guess I will find out tomorrow if they are correct :-)

proptop

My Feedback: (8)

You're welcome...[8D]

Where did you find the bearing?
I have a couple of these engines, and would like to know, for future reference. (I've asked Paul at RC Bearings, and have checked Boca, but neither one had it )

CannonFodder

My Feedback: (23)

I got them fromn an eBay store called "We keep you Rolling" maintained by 2rideornot2ride. I have not had the chance yet to pull the prop driver and so I do not know yet if the bearings truly are a match, I'm hoping to get to it this weekend.

Gray Beard

My Feedback: (-1)

Columbia, I used to go there once in a while when I was in the Army. That was really a fun town in the days of my youth.

proptop

My Feedback: (8)

Thanks for the info. Hope they fit!