Starter Acting up

Flavius Renatus

Pre-takeoff checklist
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Oct 7, 2012
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Northwestern Illinois
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Flavius Renatus
Went flying yesterday, did the preflight and pulled my 1969 Cessna 172 out of the Hanger, she has a Lycoming O-320.

Anyway, I went to start it, and instead of the prop turning over, all I heard was a spinning sound. Kind of a whirring.

I turned the key again and it did it again.

It sounded like the starter was turning but not engaging on the flywheel or whatever the thing is called.

I shut everything down, got out of the plane and turned the prop backward by hand, why? I thought that the teeth might not have been lined up or something.

Got back in, and she started right up. I flew for about 30 mins over to the local cheap fuel stop, filled up and the same thing happens.

So what is going on and how much am I anticipating to spend?

Thanks

Flav
 
Went flying yesterday, did the preflight and pulled my 1969 Cessna 172 out of the Hanger, she has a Lycoming O-320.

Anyway, I went to start it, and instead of the prop turning over, all I heard was a spinning sound. Kind of a whirring.

I turned the key again and it did it again.

It sounded like the starter was turning but not engaging on the flywheel or whatever the thing is called.

I shut everything down, got out of the plane and turned the prop backward by hand, why? I thought that the teeth might not have been lined up or something.

Got back in, and she started right up. I flew for about 30 mins over to the local cheap fuel stop, filled up and the same thing happens.

So what is going on and how much am I anticipating to spend?

Thanks

Flav

The lubrication in the bendix of the starter is sticky, soak it with WD 40 let it set over night it should work good for a while, but you do need a replacement.
 
The lubrication in the bendix of the starter is sticky, soak it with WD 40 let it set over night it should work good for a while, but you do need a replacement.

I agree with Tom...... And, cold weather doesn't help either..:nonod:
 
I have it on a heater under blankets so the engine compartment was at about 70 degrees. it has sat for about 6 weeks since my last flight.
 
Went flying yesterday, did the preflight and pulled my 1969 Cessna 172 out of the Hanger, she has a Lycoming O-320.

Anyway, I went to start it, and instead of the prop turning over, all I heard was a spinning sound. Kind of a whirring.

I turned the key again and it did it again.

It sounded like the starter was turning but not engaging on the flywheel or whatever the thing is called.

I shut everything down, got out of the plane and turned the prop backward by hand, why? I thought that the teeth might not have been lined up or something.

Got back in, and she started right up. I flew for about 30 mins over to the local cheap fuel stop, filled up and the same thing happens.

So what is going on and how much am I anticipating to spend?

Thanks

Flav

You have gunk in the Bendix grooves, use most any solvent spray like WD-40. Berryman's B-12 Chemtool (my personal choice) or whatever, flooding the starter shaft and back between the shaft and gear thingy that rides on it (that's the Bendix drive) and goes back and forth and clean it out. For giggles, look at the ring gear on the flywheel and make sure it's intact with no broken or worn of teeth with big burrs on it (unlikely) and it should work just fine. You may have to work the starter and respray a few times to get all the gunk, belt scrud and dead bugs out.
 
I'd replace it with a SkyTec NL.
 
I'd replace it with a SkyTec NL.

Eventually.... As expensive as plane parts are, I like to get full life out of them. If it just started happening and he hasn't scored it all up yet, it may still have a year or more left in it.
 
Eventually.... As expensive as plane parts are, I like to get full life out of them. If it just started happening and he hasn't scored it all up yet, it may still have a year or more left in it.

Certainly that is a possibility, and if he doesn't fly much in the winter it will probably not have this issue come springtime.

You also don't know when it will go from doing that (and eventually starting) to just not engaging. So if dispatchability is a concern, then replacing sooner makes more sense. If it's not, then waiting makes more sense.
 
Certainly that is a possibility, and if he doesn't fly much in the winter it will probably not have this issue come springtime.

You also don't know when it will go from doing that (and eventually starting) to just not engaging. So if dispatchability is a concern, then replacing sooner makes more sense. If it's not, then waiting makes more sense.

Yep, and if hand propping isn't too scary, it can be put off for a long time....:D;)
 
Yep, and if hand propping isn't too scary, it can be put off for a long time....:D;)

Also depends on your plane. In the Aztec and 310, fugghettaboutit.
 
Also depends on your plane. In the Aztec and 310, fugghettaboutit.

Went flying yesterday, did the preflight and pulled my 1969 Cessna 172 out of the Hanger, she has a Lycoming O-320.

Although, the 1340 Stearman was hand prop only and you had to start it before you could fly it...:yes:
 
I just looked at the cost of the starterr, and I think I will just replace it.

Thanks for the help.

Flav

All starters have their achilles heel. Traditional starters (Prestolites, for instance) have a Bendix. Skytec's have shear pins and fragile cases.

Choose your poison.

By the way, isn't a "dry silicone" lubricant the appropriate product for a Bendix?
 
Tom, Can he take it to a starter / generator shop for repair? Squeeze a few more years out of it? Can a certified starter be repaired by a specialty shop? Don't tell them it is off an airplane. ;)

The local A&P does it here. :dunno:
 
I just looked at the cost of the starterr, and I think I will just replace it.

Thanks for the help.

Flav

Personally I would go with Toms and Hennings idea first... Spend 2 bucks on a can of WD-40 and lube and clean the shaft... it is so easy, even a caveman can do it........
If that doesn't work, which 99& of the time it will, then you can spend 450.00 + A&P labor = about 550.00 to install a new SkyTec unit... Hey, it's only money..:yes::rolleyes::confused:
 
Personally I would go with Toms and Hennings idea first... Spend 2 bucks on a can of WD-40 and lube and clean the shaft... it is so easy, even a caveman can do it........
If that doesn't work, which 99& of the time it will, then you can spend 450.00 + A&P labor = about 550.00 to install a new SkyTec unit... Hey, it's only money..:yes::rolleyes::confused:

Seriously? A slap at cavemen? Or Geico? :rofl::rofl:
 
I'd replace it with a SkyTec NL.

So would I.

I wouldn't simply because to install one on a 172 (due to baffling) requires more than a simple bolt on.

I am a big fan of SkyTec staters however. The guys at SkyTec like me because we manage to damage their starters in new ways given the student pilot type abuse they see. I knew they were a good company when they started getting excited to hear about what new thing we had done to a starter.
 
Tom, Can he take it to a starter / generator shop for repair? Squeeze a few more years out of it? Can a certified starter be repaired by a specialty shop? Don't tell them it is off an airplane. ;)

The local A&P does it here. :dunno:

I do it when economically feasible. Swapping brushes or a bendix isn't too bad.
 
Same problem has been occasional on our O-360 the last few months. Questions:

1) I was told silicone spray as well, vice petroleum product. Pros/cons?
2) Have been thinking about hauling around spares for no-go type items (starters, mags) to keep from being stranded waiting for a overnight shipment. Do I need exact replacements, or could the spares be upgrades? Could any weekend 'mechanic-on-call' swap out the old starter for a SkyTec NL at a strange FBO, or would there be some goofy paperwork issue keeping me from flying straight away?
 
The SkyTec NL starters are strait bolt ons for most aircraft but may require some modification of its accessory tabs. If you have a 24V aircraft get the /ec model.

As for petroleum vs silicon, I know Lammar specs silicon for its lubrication, required each 50hrs.
 
Same problem has been occasional on our O-360 the last few months. Questions:

1) I was told silicone spray as well, vice petroleum product. Pros/cons?
2) Have been thinking about hauling around spares for no-go type items (starters, mags) to keep from being stranded waiting for a overnight shipment. Do I need exact replacements, or could the spares be upgrades? Could any weekend 'mechanic-on-call' swap out the old starter for a SkyTec NL at a strange FBO, or would there be some goofy paperwork issue keeping me from flying straight away?

That's a lot of stuff to carry. Mags maybe, but most likely I'd just carry spare points and condensers and I don't consider a starter a 'no go' item on an O-360, that's plenty easy to hand prop. Where does it end? Spare alternator? I'd consider that as a no go before a starter. How about a spare cylinder kit?:dunno: Personally the only spare I worry about is spare fuel, it's the most likely failure to cause problem. But then, I carry a whole spare engine and prop.:D
 
To my esteemed mechanically inclined colleagues, I was told not to use WD40 because once the lighter VOCs evaporate, you are left with heavier residues which build up. I was told to use silicone. Been using it on the same starter for 22 years. Winter is where I see the occasional Bendix failure to engage.

What are your thoughts?
 
To my esteemed mechanically inclined colleagues, I was told not to use WD40 because once the lighter VOCs evaporate, you are left with heavier residues which build up. I was told to use silicone. Been using it on the same starter for 22 years. Winter is where I see the occasional Bendix failure to engage.

What are your thoughts?

Meh, WD-40 isn't one of my favorites, but I don't see problems from it. As I said, I use Berryman's, if I need a no residue cleaner spray I use CRC Electromotive or Brakeclean, the chlorinated solvent one. You can also use it to dry up behind other solvents. Tri Flow is another good spray. I have nothing against silicon, just don't spray it around your modern car when it's running as it's not healthy for your O2 sensors.
 
To my esteemed mechanically inclined colleagues, I was told not to use WD40 because once the lighter VOCs evaporate, you are left with heavier residues which build up. I was told to use silicone. Been using it on the same starter for 22 years. Winter is where I see the occasional Bendix failure to engage.

What are your thoughts?

I think WD-40 is not much of a lubricant. Legend has it that it was designed to displace water and leave a corrosion preventative layer behind. Any lubricating properties are a by-product of that corrosion prevention layer.

Silicone grease or spray isn't a bad lube. It doesn't seem to attract dust and seems to provide a low coefficient of friction.

In general, use whatever lube the manufacture recommends.
 
I think WD-40 is not much of a lubricant. Legend has it that it was designed to displace water and leave a corrosion preventative layer behind. Any lubricating properties are a by-product of that corrosion prevention layer.

Silicone grease or spray isn't a bad lube. It doesn't seem to attract dust and seems to provide a low coefficient of friction.

In general, use whatever lube the manufacture recommends.

Hence the "WD", Water Displacement, formula #40, apparently the first 39 had reactivity problems with various other materials it was meant to be used on. My favorite application for it is as a flamethrower to kill cockroaches.
 
You're good at repeating the legend.

I remember things well.:wink2: Trade shows are good for a few things, not many, but legends are one. I'd have named it BK-1 as it does a great job killing bugs.
 
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To my esteemed mechanically inclined colleagues, I was told not to use WD40 because once the lighter VOCs evaporate, you are left with heavier residues which build up. I was told to use silicone. Been using it on the same starter for 22 years. Winter is where I see the occasional Bendix failure to engage.

What are your thoughts?

If you don't like WD 40 shoot some 1010 oil in it, that'll work too, any thing that will cut the crud.
 
If you don't like WD 40 shoot some 1010 oil in it, that'll work too, any thing that will cut the crud.

Exactly, you're not trying to lubricate, you're trying to flush out all the scrud. The thing with Lycomings that I found is the belt dust gets in the Bendix and causes them to stick.
 
Choose your poison.
By the way, isn't a "dry silicone" lubricant the appropriate product for a Bendix?

Yes, it is. The Bendix hanging up as the OP's does is normally due to either oil from a weeping crank seal getting into the starter drive, or a mechanic has been squirting oil into it. Oil attracts dust, slowly dries out, and creates a really gummy mess on those splines and the drive doesn't engage the ring gear anymore.

To get it really clean, one needs to take the starter off and take it apart for cleaning. Better in the long run to replace it with the Skytec. We had really good service out of those, and they don't have the sticky-Bendix problem. They have a solenoid-operated engagement mechanism that works every time.

Dan
 
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