Ihave an 0s46ax that I am trying to replace the bearing in, IS there a bearing puller for this motor, I have the ofna puller set I currently use along with other means of pulling airplane motors but this motor has a rear bearing thats not as easy to access.

Ken

Ken, heat is going to be your friend in doing this , there is no need for a puller for the rear bearing.
How far along are you in tearing the engine down? Do you have the front prop hub off yet? What about the sleeve and piston and rod out?
Generally once you get those out of your way along with the crankshaft, you can heat your engine in a 350° oven for about 15 minutes and with the back plate off, then get you a good glove to wear so you wont burn your hand, then with the engine block, slam it down on a piece of 2x4 or other piece of wood with the rear side of engine to the wood, and your bearing should come out with a couple of good wacks from you. If the bearing is really stuck good, it may take a couple of heat and wack cycles to get it out. If an oven isnt available, I have also used a heat gun to heat the engine block. Just dont heat the block in one place, keep the heat gun moving around on the outer part of the engine block. Go ahead and remove your carb too if you put the block in the over, you dont want to damage it with the heat
Let us hear from you on how it goes.
John

Thanks john, I do have the engine completly tore down, Iguess i just didnt add enough heat...lol Ive done quite a few 4 stroke bearing replacements and a few 2 strokes but this one just seems to be stuborn..lol...I'll try a little more heat..

Ken

You usually have to heat the crankcase up and then use a rod down through the hole to tap the bearing out of the hot crankcase. I like to use a hot air gun inside and a propane torch outside. The idea is to heat up the crankcase and not heat up the bearings as much, so the bearings stay cooler. Sometimes the bearings pop right out with a sharp rap on the table, sometimes they don't. I use a 1/4 inch brass rod that now has a bit of a lip on the end, to tap out the bearings from the inside. I use the rod though the back for the front bearing, and reverse the rod to the front to tap the rear bearing out. Sometimes the old oil, varnish, castor, corrosion, etc, tends to build up around the bearing locking it in place a little on you. You want to heat up the crankcase, but only hot enough so you have to use leather gloves to hold it, and not more than about 240 degrees F or so. Somehwere above 250 degrees F and the crankcase will expand, but not shrink back when it is cool.

I hate to be disagreeable but you're not going to hurt the crankcase at 300 to 350 and heating the crankcase in an oven is preferable to using a torch as it will heat things evenly unless you're one of those folks that does it every day.

Also, the aluminum crank case will expand much faster than the outer bearing races.

Throw it in the oven at 300 for 10 minutes and smack it on a 2x4 and it should pop right out.

Thanks for all the info guys, I normally try to use pullers when i can but this worked so easy im going to start using the oven method, the bearing poped right out with one tap...Im really liking this oven method...



Ken

I use separators and bearing pullers for prop drives. They usually pop right off. Starting off at 300 degrees is about right. I've gone up to 350.

Hi!
Pullers should not be used when replacing bearings in an aluminium case! If done that way you will damage/wear the bearing surface and the bearing will sooner or later come loose.
Only heat should be used! Either an owen or a propane torch!

I do not recommend using a torch as you have no idea what temps you are putting the case through. Strange as it sounds, both cast aluminum and hardened steels start to lose dimensional stability at around 385F. I use a small toaster oven I got at Target. I monitor the temps with an oven thermometer. No more than 350F for me.

It doesn't matter what happens to the bearings if that were true. You use a puller to get the drive washer off. Anyway, aren't those bearings getting tossed when you get them out?

Darn - could'a gotten a 5% discount on the Saito FA-82a bearings that I just swapped. The Saito hasn't gone Kablamo yet.

In my case, the old bearings came out without ANYforce or heat. The new stainless just dropped in, again, no heat or persuasion necessary.