Electric Starters and Plain Bearing Engines

All,
Do electric starters cause excessive wear in plain bearing engines, such as the Thunder Tiger 25GP or OS and other clones in that size range? I heard or read somewhere (can't remember where) that they should be used only with ball bearing engines. Any truth in that?

Thanks,
Kim Mortimore

Supposedly, the push of the starter on a sleeve bearing engine can push the shaft back against the backplate and wreak some havoc. I suspect that would be true if you put it on and grind away at an engine that isn't ready to start, the way I see so many RCers do. But I and others I have seen, have gently used starters on plain bearing engines with no notable ill effects. I mean, you can wreck an anvil with enough misuse.....

A pre-requisite for the use of an electric starter on any engine is the provision of some means of taking the (reverse) thrust of the starter.
This thrust is taken by the ballraces in a ballraced engine, so there is no problem in that case.
But in a plain-bearing engine there is no provision for reverse thrust on the shaft, unless a steel or brass shim washer is fitted on the shaft between the prop driver and the crankcase.
The better brands of plain-bearing glow engines will have this shim fitted as stock.
This shim not only takes the starter thrust, but also prevents the crankpin being pushed back into the backplate, as it can be in some engines.
It is a good idea to squirt a little fuel onto the rear of the propdriver on a shim-equipped engine before using a starter.
Lastly, if an engine does not start within 5 seconds after applying the starter, it is not going to start. It will need more fuel, or it may be flooded, or the plug may not be glowing. Stop whirring away and find out.

While it is not an admirable act, I frequently use electric starters on Fox 35s. It's not a question of being able to hand-flip them or even of being able to get a quick start. It's just what I do with all of my CL Stunt engines.

With a new engine it is nice to squirt some fuel between thrust washer and front of case, although I generally forget. Because...

What I really want to see happen is for there to develop a nice gap between thrust washer and case such that I can slip in a .010 shim which is home-made from suitable stock, old tanks being just one source of supply.

With this shim in place the problem seems to just go away; I have never had to resort to a thicker shim, nor have I had to replace cases or shims.

Most Engines with a prop mounted will not let the shaft go back far enough to hit the back of the case. I was a little surprised to see guys starting old sparkers at the Sam Champs with electric starters.

>...the way I see so many RCers do.

I'm sure there are many C/L'ers that do the SAME, EXACT thing, too. Why is it that there is ALWAYS some sort of mindless 'tension' between C/L and R/C enthusiasts. Geez, it's a hobby, it's about flight and having fun...act like an adult, not like a bunch of three year olds!

>>...the way I see so many RCers do.
>
>I'm sure there are many C/L'ers that do the SAME, EXACT
>thing, too.
Ron B.
F4Fguy

Yeah!,they do! That does't make it any less a sin.Properly used, an electric starter can be a useful tool.Unfortunately I seldom see one properly used,by anyone, RC or CL.
If you turn the engine backward against compression, put the starter in place with light pressure and then(and only then)hit the switch,you're unlikely to cause any damage regardless of bearing type.I'm assuming ,of course,that you only turn the engine a few turns to spin it up, and immediately pull the starter away before releasing the switch.If this doesn't produce a start in two or three tries,there's something wrong.Find it and correct it before proceeding.This procedure will give minimal reverse thrust on the bearing.Keep in mind though,it's still more than none,which is what you get with hand starting.

As usual, Ron nails it.

If an engine has been properly prepped and is ready to start it will do so readily with or without the electric starter. There is no more reason to grind on a motor than there is to mindlessly flip the thing over 50 or 60 times.

And while I cannot explain it, there are many times when a Fox 35 will almost immediately fire up from a couple hand flips. Right after one plonks the electric starter down in frustration.

I believe the best starting CL Stunt motor I have ever owned was a CL-specific ST 51 which I recently sold to Greg in Simi Valley, CA. At times it was scary how fast it would fire; like when I would be simply rocking the prop back and forth with the spinner, just checkin' for prime.

An electric starter can be real handy for pumping the engine clear of fuel. At least that's what we call it when the plug is loosened a couple threads. If plug is still tightly installed we call it a "rod test."

Ya know, I don't think anyone need get upset at disparaging "RC Guy" comments. By and large the radio guys have way more raw beginners in their ranks, leading to quite amusing things happening. One is grinding on a recalcitrant motor, another is in having complete faith in a new plug being a perfect plug.

I say that as a guy who has spent quite a lot of time flying RC and who is pretty good at it. If you want credentials, I taught myself--no outside assistance whatsoever--to fly RC on a 40-powered Quickee 500. Which I still own to this day, is flyable. Learned on Mode II, at the advice of Dave Shadel switched to Mode I. This involved 12 flights, alternating between that same Quickee and a 40-powered Airtronics something-or-other (low wing, aileron model), the former on Mode II, latter on Mode I. Broke a prop on one landing. Switched to Mode I.

And nobody on this forum is harder on the RC guys than I am. Probably because I can be considered to be one of them.

Lighten up...