Nightz...if you stink up your wife's oven with enough solvents, and penetrating oils....she's going to knock out YOUR bearings....

<GRIN>

I was kinda thinking maybe the small toaster oven would be ok. I can take that out to the shop. It has a 500deg broil option....should be plenty hot. I can bake it while play with the Moki on the test stand.

-Rocko

A toaster oven is what I use Rocko. I stick an oven thermometer in so I can keep track of the heat.

I use the toaster oven too. Give it a good overnight soak with plenty of the
Knock-er-loose. Then I flick some spit on the part to see if it's hot enough.

When the "spit dances" (boils) it's good and hot. The solvent will be smoking
and stinking up a storm, so the garage is the place to do the deed. Whack the
crankcase down flat and hard on a board till the bearing comes out.

Good luck

Here's another tutorial to look at for some background....

http://www.raptortechnique.com/enginebearing.htm

Thank you all for your help. I sprayed the bearing several times between last night and this evening with PB Blaster Penatrating Catalyst. This evening I put it in the toaster oven at 350F for 20min. The bearing popped out on the first wack. I wish I would have done that in the fist place. Now I have to try and smooth out the damage (Burs and little divits) that I made while trying to tap it out with a screwdriver. Thanks for all the links. I'll order some bearings this weekend and hopefully next weekend I'll have it up and running.

Thanks again,
-Rocko

Rocko,


Good!

Just do it from Paul McIntosh and don't pay for anything you don't get, by ordering from an overpriced source...

http://www.rc-bearings.com/

350 degrees is the upper limit for model engine parts. much more above that and you risk permanent deformation of the castings. Never heat hard steel parts (that you want to use again) above 325 as most hardened steels are only dimensionally stabilized to about 385.

Thanks for the advice. Hopefully i'll be ok. I used a toaster oven in a fairly cool enviroment so hopefully I didn't reach a full 350. I'll have to put an oven themometer in and see what happens. So other than the bearing that is being thrown away, the only thing in the oven was the aluminum block.

-Rocko

Be careful with the electric starter after using lots of after run oil in a 2-stroke. You can hydraulic lock the top end and bend or break the rod/crankpin easily. A short blip will do it, and even then you will notice the compression has increased drastically on an upright engine. Inverted would be even worse I imagine.

Ernie

How about of you leave the glow pug out while you do this?

How about you just try and turn it by hand before you blast it with a starter. That's why I hand start all my engines.

How about you just try and turn it by hand before you blast it with a starter. That's why I hand start all my engines.

How about you just try and turn it by hand before you blast it with a starter. That's why I hand start all my engines.

Turning it over by hand also gives you a chance to feel the condition of the bearings. Bearings usually give plenty of warning that they are failing. Loud pipes and electric starters have probably spelled death for many engines. It's best to replace them before the balls and retainer get a tour of your engine.

I'll buy that. I've hand started engines so long I almost never use my starter. Once an engine is well broken in and dialed in you never need a starter. I have never had a bearing come apart. I've seen it before. Lou Proctor once brought me an OS FS 90 that had a weird knocking sound. Turns out the retainer let go and all the balls moved to one side. This allowed the rod to hit the bottom of the case, thunk thunk, thunk. Oh and the inside of the engine was GREEN. Cool power, the "green death" had struck again. All synthetic, no castor.

The only bad bearings I had were felt fine by hand, but whined once the engine started. I don't see the need to hand start to detect bad bearings.

Finding a bad bearing is only one positive in hand starting. However I have found that a bearing that whines can be felt when turning an engine by hand. especially if warm.

This is very true. A lot of the heli guys start to notice bearings going bad only by the extra sounds coming from their engines!

What I meant by my "turn it over by hand" was to turn the engine a couple of revolutions with your hand on the prop. A bearing bad enough to soon shell out can be easlily felt. I've always caught mine by the howl, but I run mostly quiet mufflers.

I find the difference between a slightly flooded engine and normal one very subtle. One can still turn the prop over by hand, but stops after a turn or two with the starter.

BTW taking the plug off and spinning can unflood the engine but better to do it upside down, otherwise the gush of oil/fuel will start spraying, often times to those in the next flight station!

that's what a two cycle does if the crankcase is full of fuel.

I periodically check my bearings by grabbing the tips of the propellor, alternatively pushing on one and pulling on the other to see if there's any radial runout.

This almost always shows up worn bearings before they start making a noise or shed bits that might destroy the engine.

It's been my experience that once the engine starts making a noise you may be too late to prevent collateral damage.

I guess I don't have the dial caliper fingers you have. My experiance is that the bearings do not blow up right after they start whining. Both times there was several flights before the engine was pulled and repaired or sent back.