TCM just completed a long study to determine if there is any cause/effect relationship between light props and TCM engines and components. The same company now owns TCM, Cessna, Bonanza and McCauley. Mac is now introducing the lightest props that have ever been on the market to date...and the CEO's don't think they should continue putting Hartzell props on their planes when they own thier own prop company.

The results of the TCM study indicated NO Cause Effect relationship. The main cause of starter adapter/clutch failures is related to cranking RPM being to slow. These engines were designed to start at RPM at LEAST 150. Once you fall below that, you are asking for trouble.

Polar Moment of Inertia is not a static number or value. It is directly proportional to the direction and speed vectors of the mass being moved. If you have a weak starter, battery, cables, solenoid..and the starting RPM falls below the design speed, the engine will want to rotate 'backwards' to relieve the force of the cylinder that is in the middle of a compression stroke.

John

At John's recommendation, I purchased a Hartzell Continental Energizer-style starter for the 185 with the new 3-blade MT prop. I love that starter. Flips the propeller quickly without any hesitation and the motor fires up without issues. I don't know exactly how many starts I now have with the MT, but so far no issues. I did overhaul the mags and I kept the new-style starter adapter.

I recently flew with my wife for the first time since installing the prop. She thought it ran very smoothly.

adapter came back from rebuild took 3 weeks... they were busy... should be ready to go this weekend.. oh it is the weekend... I'm so confused with all these days off...cost of rebuild was 1095 plus shipping...hope that's the end of it...

Iceman, did you look at any alternatives to the starter adapter? I've been meaning to call Continental and talk to them about the starter for the IO360AF.

what alternatives... there's either an old style or a new style... you gotta have an adapter so don't know what alternatives you mean..

I meant did any of the shops you talked to mention the starter used on IO360AF. I didn't know about it till I was reading the overhaul manual a couple weeks ago. Looks like a copy of the B&C starter used on the O300, no adapter. I've been meaning to call Continental and ask if it can be used on other models of the IO360.

yes the shop told me mine is the old style and it is the same as used on another Continental , can't remember which though.. not a lot of room back there between engine and firewall I guess which is why the adapter became necessary..... They're in Tulsa... Aircraft specialties...and they got a guy who just works on adapters.. seems they have a lot of rebuilds of adapters since it is such a frequent problem...

try calling aircraft specialties... they don't mind talking about the problem... Sam is the guy who works on adapters and I guess there isn't anything they don't know about continentals... other than the time it took to get back it was a good company to deal with...and the starter guys recommended them...

850hrs later spring broke again.

Cold start makes for a lean start and that probably caused the kickback, battery had not much power also, so stars aligned and broke the spring.

Since my starter adapter had 1350hrs Niagara recommended an overhauled one.
After talking with Niagara and a couple more companies who overhauls them I decided to buy the old style adapter.
At least I know if I get a kickback it wont leave me stranded on my own in the middle of nowhere.

Old style was installed with the thicker gasket , new battery installed, using pre heat and so far has been great (knock on wood).

So 2 blade MT
O470R
Old heavy starter
Had newer starter adapter, replaced with an old style adapter.

Now since the old style adapter does not break the spring with a kickback, I assume a kickback from a lightweight MT is less stron than a kickback with a heavier prop? So more difficult to damage wind the spring and damage it?

Has anyone with an MT had a failure of the old style adapter?

motoadve wrote:Old heavy starter

In a previous post, you mention that old heavy starters are good because they turn the propeller slowly. But you had a kickback when your battery was weak and turned the propeller slowly.

Which starter do you have? If you have the old heavy ISKRA, you are asking for problems. With the heavy Hartzel energizer-style, the propeller will turn very fast, which I believe is desirable to prevent kickback situations. Anything getting the propeller moving quickly through the cylinder compressions is better than a battery starter combo that lumbers through the start.

The specific type of "old heavy starter" is an important detail. Just curious what you are running.

Just broke our Starter Adapter spring. MT prop. I thought it had the old style adapter but it turns out it had the new style. We got 700 hrs with no trouble but definitely going back to the old style adapter with original heavy starter.

TCM starter may be a safer option if you don't mind the weight... I think the adapter issue is coming up because it sounds like a good place to point the blame, but its not whats causing the kickback. With both the new AND the old, a kickback can break the adapter, its just that the older spring has more forgiveness. As stated above, the issue with the older adapter is when the spring breaks, there is a possibility that the metal will get in the motor and lunch the engine. This is why Cont issued the SB. Some feel that with a broken spring having the ability to "fly home" is a plus, but for my dime, I'd rather not risk the entire motor.

Make sure the timing is spot on, have a good maintained battery, and don't let the key slip half way thru the start. At least that's what I am telling myself until I break another and change my tune...

400 more hrs on this engine(couple of years or less) then Im going to decide which adapter for my new engine, will send again my magnetos to aircraft magneto service so he does his work on them, which reduces the risk of kickback.

I have the Old heavy weight TCM starter, had the ISKRA before , and replaced it 850hrs ago.

NZMaule wrote:Exactly.....forget about starters for a while, that sentence down the bottom about resistance to opposite rotation is the issue here with the MT and the new style adapter. In my opinion backwards rotation from failed starts or whatever is not always about a classic 'kickback' it's from the low inertia of the composite prop not going through TDC and then rotating backwards - breaking the new style springs. I've seen mine rotate backwards many times since going to the old style adapter, you won't see it happen on the new style because the spring won't let it - it will just eventually break.

Today I had one of those rotate backwards of the prop when it failed to start, I froze thinking here it goes again.
Nothing happened and cranked the engine, started and flew back home.
I was glad I bought the old classic style starter adapter.

The reason you see the prop turning backwards after a failed start.
Because of the worm/wormwheel design of the classic starter adapter, it is absolutely required that the starter motor itself actually turn backward about half a turn or so when it is de-energized following a start, so the clutch spring can release from the shaft gear drum, If this does not happen, the whole thing gets really hot fast, but the pilot has no idea, so he goes flying, and the starter adapter cooks itself, and makes lots of metal for the whole flight. It is only upon the next start attempt that any of this becomes evident.(I think this is the reason Continental went to the new style, because a bad starter can ruin your engine).

Well it just happened to me yesterday. 5 months ago put in a new style adapter, new Skytec ST5, new firewall battery, and new MT prop.

Any thoughts about electronic ignition as a potential for reducing chance of kickback?

Sorry to hear that.
You need the classic style adapter, not the new style, it will take a kickback and wont break the spring.
If its too late and you already bought the new style adapter , then shower of sparks will prevent kickbacks.

Unfortunately, old-style adapter, boat anchor Energizer starter, and heavy metal prop seem to be the ticket to avoiding kick-backs and breakage from same.
A lightweight prop has less momentum so will kick back more often /easier than a heavy prop.
Saw this illustrated many times on my buddy's 65hp Luscombe when he had a wood prop and no-impulse-coupling mags.

motoadve wrote:Sorry to hear that.
You need the classic style adapter, not the new style, it will take a kickback and wont break the spring.
If its too late and you already bought the new style adapter , then shower of sparks will prevent kickbacks.

I have seen the magneto start points wear causing timing advance even on shower of spark mags many times. Results are the same with kickback busted starters and adapters.

Which shop did you order your adaptor from? I went to the site someone quoted earlier in the thread but couldn't find the core charge on an exchange. I have a 470r swinging the usual McCauley, new odyssey batt and mags and plan to change the adaptor out sooner rather then later as I noticed it is slipping.

I don't care about weight I just want the most reliable one that isn't going to self destruct inside my motor.

A weak starter can give you the impression your adapter is slipping. Your need fast/positive starter engagement to tighten the adaptor spring with minimal slippage. I thought my adaptor was failing, turned out the starter was coming apart. I replaced it with a new tempest ball bearing old style starter and all issues gone (Highly recommended over the energizer by some adapter rebuilders due to the low rolling torque). You don't replace an adaptor and reuse your old starter without a full check. No more than 5 ft/lbs rolling torque allowed on the starter as the starter needs to rotate backwards to disengage the spring on an old style adaptor. New style adaptor does not need to rotate the starter backwards, therefore you can use a new lightweight style starter.

Which is the best? 6 to one, half a dozen to the other.