Ok, appears I had the clean spring break everyone has talked about and/or experienced. Have talked to many different folks about this issue now and boy is there ever conflicting data. I'll touch on that later...

If you look up over-engineered SOB you will find this picture [emoji12]


While on this spiral of a spending spree, went ahead and pulled my mags and prop gov for overhaul as well.

Skalywag wrote:My IA who has replaced many drives said I should be fine and it's almost always a clean break with the new style drive, I sure hope he's right.

At work we have starter drive adapters fail with regularity (our planes fly 80 - 120 hours per month). The end of the spring gets worn and won't engage or the spring breaks. In either instance, our mechanics remove and replace the starter drive adapter and send us on our way: no angst about metal in the oil. So I don't think you have any metal contamination issues to worry about.

Symptoms of the end of the spring wearing: when you engage the starter you'll hear a whirring sound, but the prop won't spin. Often if you re-engage the starter you'll get a good start. From my experience, when this happens you have between zero and ten more starts before the end of the spring is worn too much to engage.

Thanks PA12_Pilot. Do you know if your company uses the "classic" or the "new" style drive?

Most pilots I've talked to flying with a lightweight prop say the classic style with the energizer type starter is the way to go.

However, I've spoke with the owner of Niagra at length, he said neither is a great setup but that he would definitely go with the new style. Apparently, the old style will allow a kickback but distort the spring, thereby allowing the drive to still engage for starts but not completely disengage, thereby heating up the drive while flying with potentially disastrous results. With the new style it's almost always a clean break of the spring and if your out in field you can just prop it off and be on your way.

FWIW I got three starts from when it started acting up, no kickback until the third when it broke

Skalywag wrote:....If you look up over-engineered SOB you will find this picture [emoji12]

Take a look at the one on the O-300D -- they added a vacuum pump drive pad to the aft side!

Skalywag wrote: ....While on this spiral of a spending spree, went ahead and pulled my mags and prop gov for overhaul as well.

I don't know who's gonna OH your mags, but you might wanna take a look at Aircraft Magneto Service's website first.

http://www.aircraftmagnetoservice.net/

The Bendix mags on my C180 have 1200 hours on them & near as I can tell have never been touched, so I thought it would be a good idea to have them looked at. Cliff at AMS told me the difference between a "500 hour inspection" and an "overhaul" is that replacing certain parts is mandatory per the Bendix OH manual, whereas with an inspection he just replaces the parts actually needing replacement. Therefore the OH is almost always more money (certainly never any less). With that in mind, I told him to do an inspection-- the bill was about 525 for one mag, and 625 for the other.

This thread scares me a little. I've been planning on a TCM with a big Mac with a hopeful upgrade to a MT in a few years. I'm starting to wonder why I'd install such a combination when my options are limitless.

Good luck Skaly, hope you find the right solution and this becomes a non issue.

What scares you? The possibility of an expensive problem? That possibility exists no matter which engine / prop you choose. Lycoming doesn't have starter drive issues like a big Cont, but the cam issues which they do seem to have sometimes aren't cheap either. If you want a C180 you're gonna be stuck with a Continental, if you want a newer Maule you're gonna be stuck with a Lycoming. An older maule, a Continental or Franklin.You are in the enviable (or not) position of being able to choose your own poison, but no matter which you choose it'll have it's good & bad points. Close your eyes, put your finger down, and pick one. Then start saving money for if and when it shits the bed.

Whee, give Ron at Niagra a call. He has some solutions in the works and being in the home built category may have some options for you to consider.

Also, this starter drive issue is for all props and 470-520-550 continental engines. First problem I've had in roughly 1500 hours on 470's so take that FWIW too.

I'm no mechanic, so take this with a grain of salt. I saw on another forum some comments about the starter adapter breaking, which was caused by either the "retard breaker" not working (broken wire) or the mags put on the wrong sides (left on the right and vice versa). In both cases, the prop would make a slight swing backwards at the beginning of the start, which soon led to the adapter breaking.

If that helps, great. If not, disregard it as coming from someone who knows which end of a wrench to use, but not much more.

Cary

Here is an interesting website that has some good info on starter drives. Make sure to scroll down and read some of the comments.

http://www.csobeech.com/adapter-mystery.html

Well i had hoped against hope with the Skytec and MT combo that this happened only to the "other guys," but alas when i finally went to go fly for the holiday weekend i had a subtle kickback and snap... Course i just installed re-built mags at annual so perhaps the timing is off, but more likely its due to the starter slipping... Hopefully its just the spring.

Fuckers

Most likely the spring is what broke.
Get rid of the Skytec starter and buy the old style slow turning heavy one.

It happens to everyone who gets the MT prop and has a lightweight fast moving starter.

Probably more important than the Skytec / MT component is Which Skytec and Which adapter... Choose the wrong combo of those and it won't matter what prop you have on the nose, you will suffer a broken spring on the inevitable kick back (see Eric's post, as I'm sure they're not running MT's )

motoadve wrote: It happens to everyone who gets the MT prop and has a lightweight fast moving starter.

One of the reasons I rarely use absolutes in aviation is that there are almost always exceptions... I have run three MTs turned by Skytec's, had the inevitable kickbacks, and haven't sheared a spring yet... and I am not the only one I know of doing this

Take care, Rob

Maybe less powerd engines dont get the kickback, or ycomings.
I see many Huskys coming out with MTs and having no problems.

I should have stated it happens to everyone with a 182

motoadve wrote:Maybe less powerd engines dont get the kickback, or ycomings.
I see many Huskys coming out with MTs and having no problems.

I should have stated it happens to everyone with a 182

Perhaps you meant higher powered engines, although that wouldn't have been any more accurate My three MTs have been on a Pponk O-470-50, and although in my case it's a 180, I doubt they would have cared which end the little wheel was on. Still curious which adapter bigrenna just broke.

Bump. How you getting on with this bigrenna?
I'm also curious which starter adapter - I'm picking new style adapter and a clean spring break?
Since changing to the old style adapter I have seen my prop rotate backwards on several occasions which I'm sure would have snapped the spring in the new style adapter every time.

Rob do you have the 2 blade or 3 blade?
I imagine the 2 blade is more to break the starter adapter because its lighter?

Has anyone ever had any troubles with a Lycoming doing this? The Lycoming uses an adapter, but it's not a right angle drive, it's same axis. Can it still suffer the same fate if there's kick back?

motoadve wrote:Rob do you have the 2 blade or 3 blade?
I imagine the 2 blade is more to break the starter adapter because its lighter?

Take your pic I've ran multiples of each, and have had kickbacks with either flavor...




Still curious which adapter bigrenna broke? I'd bet NZ is spot on

Zzzz, either engine can kickback and do bad things, the trouble with the Conti's is that the engine oil passes through it, so breaking one, whatever metal you made is going to make at least one lap through the system.

Take care, Rob

I had a new style adapter. Indeed the spring broke in the center. Ordered a new style adapter and put the old TCM energizer back on. Hard to pinpoint the insult exactly... We just installed rebuilt mags at annual, so it could have been a slipped/missed timing issue, the skytec, or just age. Adapter had 1100 hrs on it.

If you dont know what folks are talking about RE: the spring, you can see it wrapped on the gear shaft in the pic above. The one on the right has the broken spring. You can see that it has migrated toward the camera a bit. The break is a bit deeper inside the housing.

The root of the issue here is with the MT prop. If you choose to run the MT on the Cont, I would say it's probably safe to assume you should expect to break an adapter at some point. Of course this may never happen and for sure some will cry BS, but IMHO a non-biased owner would be wise to expect it. There is just not enough mass to carry the prop thru the compression stroke if there is a kick back. If you ask Cont, they will tell you the same and recommend not using the prop. Of course MT US and Germany will say its fine, but as more and more issues present themselves it is getting harder to avoid the evidence. There is a big battle brewing now between Cont, Cirrus, Skytec, and MT with each pointing the finger at the other. Time will tell...

At any rate, the new style adapter was installed ($1k ouch) which coincidentally was also the strong advice of Ron from Niagra Air Parts. When asked his best advice to avoid this issue in the future, he surprisingly advised to take the MT prop off and put it on the shelf, at least until he got approval for his faster turning starter which is in the approval process. While not ready to do that quite yet, he has a persuasive argument. Ron also recommended running ElectroAir electronic ign as this would provide a more precise timing. (don't know if my pocket book is ready for this...)

Sometimes to get the adapter out, you have to pull the motor, or at least pull the mounts and tip the engine. I was lucky and we were able to just slip the adapter out with just a cut knuckle or two. All in all, the swap was no biggie. (just a kick in the pocketbook)



RE: Running an old adapter: Yes the old style adapter can survive a kickback a bit better than the new, however is not advised to run the old style starter adapter due to catastrophic engine failure in some circumstances. There is even a a Cont SB out for some 520's and 550's. (MSB11-4B)

Lots of "internet" info for an individual to wade thru. Fact is that the stock stuff works pretty well. Once you start modifying, you should expect that some systems will start to get out of balance, and when that happens, stuff breaks and you spend more $$$. You pays your monies you pays your chances...