After run oil or Rust?
 

http://www.rcuniverse.com/forum/atta...mentid=2191608
There is a ton of oil in it, and there is definitely some rust, does it look bad?
I picked this motor up on ebay used, it looks new on the outside, the piston looks new, you can tell the motor has never been mounted on a plane, only a test stand.
I'm thinking it's seen maybe 10 ounces of fuel on a stand then got thrown on a shelf for the last couple years.
This is a OS 91fx

That appears to be mostly dried castor, my guess is that the bearing balls are stuck in the cage and will be hard to get loose. If you are adept at changing bearings I'd change them.

https://www.bocabearings.com/product...=FX&feature=91

Yes , someone ran it and put it away wet. There is rust in there as well as glow fuel is a moisture magnet.

You could soak it in some PBBlaster or cook it in some antifreeze to get it cleaned up and running but the bearings will more than likely need to be replaced.

Hey Brian, I'm a western Pa. guy, i grew up in Beaver County near the Ohio river. I change all suspect bearings, for $11.88 you can't go wrong.

Just soak it in some fuel and check the bearings after. My experience is that there is usually no rust when covered in castor varnish as this appears to be. But not always. Most likely the bearings will be fine after dissolving the dried castor oil and varnish. Anti freeze would work also but be sure it is well oiled after flushing it out.

Well the motor does spin freely, actually before I took the back plate off the motor felt great just spinning the crank, last night I sprayed the heck out of it with PB penetrating lube before putting the backplate back on, when I get the time I'll tear it down completely.
Thanks for all the advise guys.

Does anybody know a website where I can find bearings?

What Dave said above about the bearing website, BOCA bearings. Dealt with them before, excellent outfit.

Ahh I missed that, awesome will check them out, thank you, much appreciated

Most any bearing supply house will have them on hand, just take the old ones with you. Locally I can do the deal in just a few mins. and for cheap! (go for the good ones )

I've gotten several "lightly used" engines that looked similar or worse than the engine pictured above. I personally use a regimen of acetone soaking for 30-60mins, blow out with air, rinse with acetone again, blow off with air, and add oil. At this point if the bearings feel pretty smooth, I'll run it and check the bearings after a few tanks of fuel. If not butter smooth (or rather - if they make any noise whatsoever, I replace the bearings.

This example goes to show why an unrun engine is worth more than one that has had ANY fuel put through it.

I've got a few motors that I'm a little worried about that I will probably take to work with me, I'm a painter, I mostly paint wall and floor paneling for Boeing, I've got a huge clean tank with acetone for cleaning my guns so it would be perfect for soaking a couple of my motors, not to mention 250psi air gun

Is kerosene good for cleaning engines? I know it is good for storing engines long term.

For gas engines yes, but not for glow engines. Use methanol to remove congealed castor oil. To remove baked on castor varnish use antifreeze warmed in a crock pot, or oven cleaner.

Antifreeze works pretty good but it can't be the premixed Antifreeze, it has to be the concentrate, it has a certain ingredient in it that the premix doesn't have.

Glow fuel works fine for oil and residue, but only to a point. Acetone works much better for dissolving the varnish I've found. The crockpot antifreeze trick works well, but it has to be heated and given at least 6-8hrs to do its best work. Most guys use the green Ethylene Glycol undiluted, but some have had success with the extended life types (propylene glycol). Either method will require complete removal of the solvent, drying, and oiling immediately.

Ive had great success with engine bearings from rcbearings.com and equal success using bearings from AvidRC.com as well. Avid is dirt cheap ($1 each) and seem to be identical in every way to what RCBearings sells (which are the same thing as Boca's econo bearing sets). If you use coupon code "shout" you get 5% off your order or "RCU" for 7% off your order at RCBearings.com.

I ordered a set of bearings on eBay for the 91 for $12 there Abec 3 direct replacement, surprisingly Boca bearings didn't sell any for the 91fx, it wasn't even listed, plus they are exspensive at $50 for a OS 25fx bearing set, seem pretty steep to me.

Woops

https://www.bocabearings.com/product...=FX&feature=91

Here ya go

Not sure what website I was looking at, obviously not the right one, thanks Dave

Just bought another used motor, this time from the RCU marketplace, it's one of the better 91 two strokes as far as power to weight ratio, It's the Evolution .91nx, has a total weight with muffler of 20 ounces.
i just hope this motor doesn't look like my 91fx inside.

Propylene glycol is not used in automobiles. The extended life antifreeze is ethylene glycol with corrosion control other than the traditional silicate solutions.

One of the best you can get as far as any metal parts on your engine goes. The trouble is any rubber part in a glow engine does not like Kerosene

Since methanol will eat up rubber glow engines do not have rubber parts. Go back to the gas engine forum and quite pretending to know glow engines.