I have an OS 46fx that is rusting through bearings. I had recently replaced both bearings due to corrosion, and now after a max of 2 hours running, the rear bearing is rusting.

This engine has always been run dry, and I have been running no nitro, 20% klotz super tecniplate. The original bearings had rusted due to water in the fuel, and then the replacement bearing rusted. Now the new bearing is starting to rust. Very disappointing. The counterbalance had some corrosion on it, and around the rear bearing has corrosion.
I took apart the engine and some orange fluid dripped out. I washed out with methanol and dryed with a hair dryer. What should I do now?

To top it off, the liner is starting to peel[].

The engine has not had a heap of running either. It runs fine so I would like to say its a great engine, but I cant...This is really starting to annoy me, I shouldn't have to deal with these problems.

Stefan

Hey I think the problem is the fuel. check with the supplier if he didnt accidently put Sulphuric acid in it..

WARNING: CHANGE FUEL NOW OR THE ENGINE WILL GO NUTS FOREVER

I have been mixing the fuel myself. I have been running this on fresh fuel. Only thing I can think of is the methanol I brought has water in it, but that was fresh too. I store fuel in airtight containers away from light...

Stefan

Stefan
Do you have something against using some castor oil in your fuel or using a good after run oil at the end of the day? Klotz oil is an all synthetic oil and is not gererally rcommended by itself for ABN type engines. If an all synthetic oil fuel is used an after run oil is a must to coat the parts in oil to prevent rust. Synthetic oil does not leave a film on the parts and runs off leaving them exposed to moisture from the air. Some climates are worse than others as they have a lot of humidity.

I had an 46FX that the liner started pealing. I sent it in to Hobby Services and they replaced the piston, liner and both bearing. Your engine must be a older one or has a older liner because they claim to have fixed that issue about 2+ years ago. [>:] By the way, the repairs only cost me shipping to them. Also my engine has always had some rust in it. As long as it dosen't affect the rollers of the bearings I don't worry about it.
Send it in, get it fixed, and fly the hell out of it!!!

Not true--
I use all synthetic fuel in my helis with no after-run.
No rust, no corrosion, build-up of gunk or bad bearings.
New synthetics have additives that coat and protect metal surfaces without the gunk and build-up that Caster leaves.

All my engines that are run on caster or blends have these problems.
They must be drenched with after-run over winter or the bearings will be rusty by spring.
I have too many planes to store in the house so they hang in the garage all winter, which doesn't help.
I used to swear by Caster because I'm from the old days when it was the best you could get for a glow engine.
Synthetics are proving to be a better lubrication in all forms of racing these days, whether engine or driveline.
Our glow engine are no different.

These are two engines with similar run-time and age---see for yourself.
Kirk

I use fuel with a caster blend and after run oil after each flying session,some of my engines are close to twenty years of age and still being used

Boom,

I'll have to disagree on the synthetic being better than castor subject. Synthetics may be cleaner than castor/blended fuels, but the protection, whether it be in the air or stored in your garage, is nowhere close to being as good as castor. Sure, synthetics may protect an engine just fine, but that's as long as the engine's run at a reasonably rich setting. But, let that engine run just a slight bit lean, and the damage has already been done. Castor, on the other hand, will protect that engine at that lean setting, and no harm will be done at all. As for castor gumming up an engine, maybe, just maybe, if you're running total castor for a long period of time. I rest my case on that subject.

As for synthetics being better for an engine than castor during storage, I don't know this, but I'd say that castor would be better, simply because it's thicker, and adheres to the metal better. If you're getting rusty engines during storage from them being lubed with castor, something is bad wrong! You don't get a rusty engine from using castor, no matter if your garage is on ocean front property.

I'm not arguing with you, I'm just disagreeing strongly.

John

Regardless of the merits of synthetic, wildthing is clerly having rust problems using it. Therefore I would suggest the simple expedient of a bit of castor in the fuel and use of an after run oil. There is certainly nothing to loose by giving it a try.

The clean engine shown has had quite a few lean runs and some very bad abuse when it ran wide open with no load after a crash.
It had a near meltdown when the case line for the Perry pump broke causing a very lean condition. By the time I got it down, it melted the plug and was EXTREMELY hot. No burnt piston, scuffing or dis-coloring. It's had quite a few cases of fuel through it, is clean as a pin, all original, and runs like new. It has never had after-run or run dry and is stored right next to the planes. Notice that even the exhaust port and the inside of the crank are spotless. I've NEVER seen that with Caster! My other two heli engines look just like this.
All the guys I fly with, from beginner to expert use 100% synthetic in there ABC and ringed helis. I've seen plenty of lean runs and seldom any damage from it.
In my experience, the engines are protected just as well as with Caster.

The other engine just had the bearings replaced a little over a year ago and are already rusty. It's not run on all Caster but a blend. Though most aren't this bad, all my engines' run on Caster look like this even with some after-run in them. If the Caster gum is suppose to protect the metal surfaces, why are they rusted and pitted when they're cleaned up, not shiny and smooth? Sure, Caster has proved to protect against lean runs, but a lean run has never caused me the problems that rusty bearings have over the years.

I've heard a million different theories over the years as to why Caster is good for an engine. Up until recently, I was an advocate too. I just haven't seen engines this clean and shiny with this much age, use/abuse and the only thing that is different from the rest is the oil. It's just what I've experienced.

Kirk

Oh, By the way, the oil I am running is Klotz super tecniplate, which is a mix of 80%synthetic and 20% castor. I have nothing at all against running castor in the fuel, and I find a mix of both gets the benifit of both oils. I always tune to the rich side of peak.
I will probably just run it the way it is. I doubt i will be able to get the piston/liner/bearings replaced. Like I said before it runs just fine so I guess i will keep running in this shape.

Stefan

I'm no expert but it seems obvious to me that you've got some bad methanol and/or you live in a rain forest.
The methanol must have water in it if you're getting rust as quickly as you say. It's best to store fuel and raw methanol in a can or dark place. Light can cause it to warm and create condensation.