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How to break your starter, again

This is really embarrasing but perhaps it will help someone.

The first time, I broke my starter and destroyed the ring gear. That was because, in part, I had mis-labeled left and right mag wires in my wiring kit which eventually resulted in starting on the normal magneto instead of the impulse coupled one which in turn caused kick-back. Sky-Tec rebuilt/repaired the starter for a reasonable fee. I fixed the wiring and thought my problems were over. This was late last year. As revealed below, there was a second problem.

Fast forward to yesterday. Smaller kickbacks. Grinding noises. Finally, away from home, of course, the starter would not engage the ring teeth enough to rotate the prop. A good friend flew to where I was, hand propped my airplane and I flew it home. The starter casting was found broken (the casting) again, in two places. I just knew I had to be at fault, consulted Superior. Yes, it was me, again. Then I got my RA and sent the starter for repair again.

The engine is Superior's IO-360 Plus 180 HP with their standard updraft FI. I had been starting from "cold" with mixture full rich (like I always did in my C-150). It turns out this causes many problems and accounts for my second episode of kick back and starter damage. As an aside, a similar issue was the cause of some "blown out" Ryton sumps. My sump is the standard cast aluminum and survived. Correct procedure is on page 34, I think. Mixture rich, pressurize the system with the aux. pump, turn off the pump, THEN MIXTURE LEAN CUTOFF, then engage starter, push in mixture as it starts. That part in BOLD is what I did not do and should have. BTW, the manual doesn't say to turn off the pump but at least I got that right.

I had been using approximately the correct method for hot starts, but very wrong for cold starts. They were amazed I was able to start it at all. It might have been better if I had not been able to because then I might have re-read the manual. My father always said that if all else failed, read the manual.

All sympathetic and/or educational comments welcomed. Gloating and calling me dumb, well maybe you can restrain yourselves. Thank you.

Your proceedure is what I always use to start FI engines on all kinds of airplanes. It's the only proceedure I know that crosses over between all the systems I've worked on. Moving the Mixture to ICO is probably not a complete solution to you problem, but time will tell. I would think that you should just try a little less time on the boost pump. I do know plenty of people that use that suggested mixture to ICO, but I've never done it that way, it seems like a lot of unnecessary lever movage for now reason. You either have enough fuel, too much fuel, or not enough fuel. It would seem that your problem was that you had too much.

Any possibility you have too much spark advance? A rich mixture doesn't necessarily cause a kickback, but 35 degrees of spark advance sure will.

Quote:

Originally Posted by Yukon

Any possibility you have too much spark advance? A rich mixture doesn't necessarily cause a kickback, but 35 degrees of spark advance sure will.

No. It is correct. But your point is clearly relevant.

Quote:

Originally Posted by osxuser

I am simply telling everyone exactly what A. one of the experts at Superior told me, B. what it says in the operations manual for that engine. I use very little time on the boost pump, only enough to get a change in audible tone plus .5 - 1.0 seconds. Yes, I had too much fuel, since with fuel pressure and the mixture open to any degree, the fuel is flowing into the intake port.

I'm not sure that this applies to your problem but about a year or two a go Superior had a bunch of bad ring gears. They were prone to loosing teeth. After some conversation, two flywheels and 8 starts later they admitted there was a problem with a new venders ring gear. They sent us the other design (obvious difference) and 150 hrs later it's just working fine. The main difference was the good ring gear looked anodized and the bad one looked silver. The silver one appeared not to have a proper radius cut at the base of the teeth. Larry

I think mine is OK - and another observation

Quote:

Originally Posted by LARCO

Mine looks sort of gold color and is a recent replacement.

Also, I should mention that either the starter is a little weak or the engine is really tight. It is not unusual for the first attempt at starting to result in some movement and then the blade stops. Then, the next try goes all the way around. This could be part of the problem, but I don't really know.

Correct amount of retard on impulse mag????

I'd check to make sure your impulse coupled mag has the correct amount of retard (LAG) as there are different ones out there. Your lucky the starter broke and not the case. I've seen a few cases trashed when the kick back was bad enough to bust the case where the starter mounts. :eek: that then involves a complete teardown :o ouch. Hope you find the problem. I really don't think it's a mixture issue, timing is my guess.

I'm using a very small 15 lbs battery to start my High Comp Lyco and one thing that I do is hit the starter, let off of it when the prop comes back off compression then hit the starter again when the prop starts going back the direction of rotation, this takes a lot of load off of the starter and your not trying to spin the engine over when a cylinder is coming up on compression. Been working for me for along time.

I was always taught to start FI engines at mixture cut-off as well and I've gotten backfires (or what sound like backfires, anyway) frequently on the few times I'd neglected to do that.

Ok, so I don't really know if there's a correlation or if it's just a coincidence in my case but I'm guessing there's a correlation. Does anyone know why this is? I've always just done it like this because that's what I was taught but I don't know why.

Mixture likely not the issue

I have a Bendix FI Servo as well, standard sump, Skytec starter. I used to follow their standard recommended COLD start procedure with the start on ICO until my A&P-IA and experienced CFI friend suggested COLD starting with full rich. I find that for cold starts it is a much smoother start up. If anything, I was getting kickback on the ICO Cold starts.

For HOT starts, absolutely yes, you want it to be ICO or you will never get it started.

Agree - check those mags for timing.

Sorry to hear about your starter woes,

Rob

I think your problem is your starter. The lightweight Skytec starters are junk, pure junk. Mine is setting up on the shelf of my hangar. After about 20 hours, it sounded like a quarter rattling around inside of an empty tin can. The permanent magnets cracked and came loose.

I tossed in the junk pile and got myself a new B & C starter. Problems solved.

I know all the posts to follow will extoll the longevity of their Skytec starters. Count yourself lucky. Just look at one of these next to ANY OTHER starter and you'll see what I mean.