Starter not disengaged

SixPapaCharlie

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I rotated my prop by hand and noticed a clicking sound I hadn't heard before.
I looked and the starter gear was still forward, engaged to the big gear.

I pulled the plane out, started it and everything was normal. Flew a lap, landed and looked and it was retracted (normal).
I mentioned this to a friend who said do not fly the plane again. You can do serious damage to your electrical system. Go buy a new starter ASAP.

What say POA?
 
I rotated my prop by hand and noticed a clicking sound I hadn't heard before.
I looked and the starter gear was still forward, engaged to the big gear.

I pulled the plane out, started it and everything was normal. Flew a lap, landed and looked and it was retracted (normal).
I mentioned this to a friend who said do not fly the plane again. You can do serious damage to your electrical system. Go buy a new starter ASAP.

What say POA?

I wouldn't fly until a mechanic has diagnosed the problem. What would concern me is that somehow the starter was engaged when you last flew the plane.

Questions I would be asking are, how did the starter get engaged after or during last shutdown? Did that occur somehow while the engine was running? What are the effects of having the starter engaged for some unkown period of time while the engine is running? Could this happen again?

I'm pretty conservative when it comes to my power system.
 
Sounds to me like a new video idea

Your A&P needs to look at it, before you need a new starter.
Not sure what particular starter you have, but there should be some sort of spring holding the pinon away from the ring gear. You either have a sticking pinion (lube it up) or the spring is broken.
When the engine turns faster than the starter it should automatically kick the pinion out of engagement. If it stayed engaged during flight your starter would be shreded to bits due to overspeed.
 
Chances are a good cleaning and lube of the starter Bendix drive will solve your problem. Means pulling and partially disassembling the starter though.
 
If you hit the starter, but the plane did not start, the starter will stay engaged. Did you try to start it but yet the plane didn’t start? If so, sounds to me like it’s working like it should.
Honestly, I don't recall. I don't think so just because I can't imagine why I would do that but I guess there's always the possibility when I took the key out I accidentally turned it maybe I don't know I don't think so but it's not out of the realm of possibility
 
How’s your battery?
I think it's okay but I don't know
II've had this plane for 2 years and since day one every time I started it acts like it's struggling. Initially I thought the battery was dying but I kept not replacing it and so I still have the same battery I talked to a mechanic and he said it's probably either a grounding issue or there's an AD on the battery cables.

All of that is to say if you were to try to start my airplane you'd say oh my gosh this is a weak battery but it's been like that for 2 years so I don't think the battery's weak but this also points out the fact that when the battery does finally get weak and die I won't know it.
 
some of them have hypnotizing power, crushing all that cower. sounds like your battery is here to stay.
 
So you think it's a powerhouse of energy with never-ending potency?
 
All of that is to say if you were to try to start my airplane you'd say oh my gosh this is a weak battery but it's been like that for 2 years so I don't think the battery's weak but this also points out the fact that when the battery does finally get weak and die I won't know it.

It's the same with my Comanche. Starting it is a pain in the a**. Battery is good. Mags are good. Once it runs, it's just purring along but getting those three blades running is difficult. Maybe a Comanche thing? Sorry, no idea about your starter issue. I had the opposite problem on my Cherokee once. Pushed the starter and heard it spinning but wouldn't engage the big gear. Called the mechanic and he told me to just move the prop through by hand a few times and try again. That fixed the issue and I never had that issue again afterwards.
 
Nothing a grand or two won’t fix. I wouldn’t fly it either until it’s looked at. Many planes have a starter engaged light.
 
This happened to me just today. Tried to start, starter was weak and wouldn't crank it over, leaving the pinion engaged so I couldn't even hand prop it. I suspect a starting circuit issue as the battery is new. It's happened before. Fortunately I was able to jump start it and go flying, now I'm working on diagnosing it.
 
Well, usually, if you hit the starter and the engine doesn’t start, the bendix remains engaged. It retracts once the engine starts. This used to be an easy way to lube the splines of the bendix on the old Prestolite boat anchor.
 
Now I'm racking my brain to see if maybe I turned it over. I can't imagine or remember doing it.

That has to be what happened right The only alternative would be that my prior flight which was an hour and a half the starter was engaged the whole time which sounds like would have tore it apart.
 
I once started up a 182RG, and upon turning the key to the start position, the engine fired up but something didn’t seem right when I released the key from the start position. I immediately when mixture idle cutoff and shut down the mags and the master. My suspicions were confirmed when as soon as I turned the master switch back on the prop started turning! Turns out the relay arc’s and was stuck on engaging the starter, even when the key was out of the ignition. We added a few taped on signs over the master and outside the plane in addition to our squawk write-up lest some get inadvertently cuisinarted just turning on the master.
 
I once started up a 182RG, and upon turning the key to the start position, the engine fired up but something didn’t seem right when I released the key from the start position. I immediately when mixture idle cutoff and shut down the mags and the master. My suspicions were confirmed when as soon as I turned the master switch back on the prop started turning! Turns out the relay arc’s and was stuck on engaging the starter, even when the key was out of the ignition. We added a few taped on signs over the master and outside the plane in addition to our squawk write-up lest some get inadvertently cuisinarted just turning on the master.
Wow sounds dangerous. seems like the first thing to do is disconnect the battery somehow?
076_4.jpg
 
I think it's okay but I don't know
II've had this plane for 2 years and since day one every time I started it acts like it's struggling. Initially I thought the battery was dying but I kept not replacing it and so I still have the same battery I talked to a mechanic and he said it's probably either a grounding issue or there's an AD on the battery cables.

All of that is to say if you were to try to start my airplane you'd say oh my gosh this is a weak battery but it's been like that for 2 years so I don't think the battery's weak but this also points out the fact that when the battery does finally get weak and die I won't know it.
The first 10 years I had my Cherokee it was sort of like this, but maybe not quite so bad. A "normal" start took a few turns of the prop, and it was not unusual to have to reprime and crank again, or maybe even a third time before the engine would catch. I replaced the battery a couple of times over that period with no change in starting behavior.

Eventually, the 23-year-old starter conked out and I replaced it. NIght-and-day difference in starting: Much snappier during cranking, and it starts in 2 or 3 blades.

(The old starter was a Kelly e-Series. The new starter was the same, except with a Hartzell label on it now.)
 
That I don't know and that is the thing my Comanche but he said there was an AD on
In case you don't know, "Bogert Aviation" sells STC copper cables that would probably improve your starting.
 
Personally, I always start my engine with headset off my ears. I like to hear the engine clearly.

I'd try to start the plane and see what happens. If it starts and the bendix retracts, great. Lube the bendix and move on. If you hear a rattling racket after starting, shut down immediately! The bendix did not retract and the engine is driving the starter. The sound is unmistakable.

If during starting, the bendix is intermittent--that is, the starter whirs freely and the prop doesn't--then the bendix is not engaging. It's gummed up. Sometimes, repeated tweaks of the starter will jerk it free. If this is happening and once started the bendix disengages, after shutting down the engine, tweak the starter to throw the now warm bendix into the ring gear. Leave it that way for starting the next flight. Obviously, this is not a fix. It's a temporary hack to get you home and deal with the issue properly.

Copper battery cables are a must.
 
Of all the guesses on this thread, and that's all they are, maybe two are correct.

The Prestolite starter on the Lycomings has a special Bendix drive that latches the gear forward when it engages, and it has centrifugal releasing mechanism to release that gear once the engine starts and the drives spins up, and the gear retracts. The latching mechanism is there to prevent the drive disengaging if one cylinder fires but the engine doesn't quite start yet.

The drive runs on a spiral spline on the starter shaft, and the drive's weight and inertia cause it to run forward when the starter suddenly spins. If a cylinder fired without the latching, the drive will spin itself back on that spline, and then the starter will grind the gears trying to get it re-engaged.

So what it was doing is normal.

Several suggested oiling the drive. DON'T DO THAT. I have had to fix too many sticking drives (won't engage) because some mechanic or owner squirted oil or WD-40 or LPS or something in there. It attracts dust, water gets at it too, and the three components form a sticky sludge that causes the drive to refuse to engage, and all you get is that disappointing whirr just when you want to go flying on a nice day. The starter has to come off and be taken apart to clean it up, and then it is lubed with dry silicone spray lube.

From a Cessna manual:

1707587564977.png

From a Prestolite starter maintenance manual:

1707588467941.png
 
II've had this plane for 2 years and since day one every time I started it acts like it's struggling. Initially I thought the battery was dying but I kept not replacing it and so I still have the same battery I talked to a mechanic and he said it's probably either a grounding issue or there's an AD on the battery cables.

It's the same with my Comanche. Starting it is a pain in the a**. Battery is good. Mags are good. Once it runs, it's just purring along but getting those three blades running is difficult. Maybe a Comanche thing?
The above two quotes would tell me that there are likely old, worn, or burnt master and/or starter contactors. There are a LOT of batteries and starters replaced because they don't seem up to the job, when the real problem is often a tired $40 contactor.

The starter current goes from the battery through both of those contactors. One can find the bad contactor by measuring a voltage drop across those big terminals while cranking. Voltmeter red test lead goes on the battery side of the contactor, black on the bus or starter side. Whatever voltage you see there should drop to zero when the starter is cranking. Might have to set the meter to 3 volts to get an accurate idea. If you see a drop of a volt or two, that contactor is definitely shot, and your starter current is heating the contactor contacts instead of feeding the starter enough energy.
I once started up a 182RG, and upon turning the key to the start position, the engine fired up but something didn’t seem right when I released the key from the start position. I immediately when mixture idle cutoff and shut down the mags and the master. My suspicions were confirmed when as soon as I turned the master switch back on the prop started turning! Turns out the relay arc’s and was stuck on engaging the starter, even when the key was out of the ignition.
That's what tired contactors do. Their contacts get rough from arcing, make resistance from that roughness and oxidation, and get hot enough to fuse together. Some will wear the contacts so badly that they mechanically mesh together and get stuck. They only have a light spring to disengage them.

Trace the circuit on this diagram from a Cessna POH. Other airplanes are built the same:

1707590333828.png

The yellow line is the path, from the battery to the starter, running through both the master (battery) and starter contactors (solenoids). Often neglected, too, are the battery and starter/engine airframe grounding. The current runs through those, too. Ohm's Law tells us that the tiniest resistance with large current flows will create big voltage drops.
 
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I rotated my prop by hand and noticed a clicking sound I hadn't heard before.
I looked and the starter gear was still forward, engaged to the big gear.

I pulled the plane out, started it and everything was normal. Flew a lap, landed and looked and it was retracted (normal).
I mentioned this to a friend who said do not fly the plane again. You can do serious damage to your electrical system. Go buy a new starter ASAP.

What say POA?
6PC, Can you tell us what kind of airplane, which engine, and what brand starter you have? The answer varies based on those details.

Assuming (!) you have a Lycoming, then you either have a Prestolite starter with an inertial Bendix, or you have a lightweight starter, most of which have a solenoid to engage the starter. Given that you had the starter engaged with no power, it's probably a starter with a Bendix. (There were a few lightweights with Bendix, but not the best idea...) As others have noted, this is completely normal if there was a previous energization of the start circuit that didn't result in a start, as the Bendix needs to be over-driven (turned faster by the engine than the starter motor allows) to disengage. Or, someone pried the Bendix into position with a screwdriver, but it seems unlikely you'd not know about that.

The Bendix comes from the overhauler with a sticker directing a spray of silicone lubricant at each oil change to keep them from sticking. If the Bendix is a gooey, greasy, dirty mess, it may need to be cleaned up with solvent before the spray of silicone can do any good.

If you have a Continental engine, that it can be a whole different group of problems... so let us know!

Paul
 
I rotated my prop by hand and noticed a clicking sound I hadn't heard before.

6PC, Can you tell us what kind of airplane, which engine, and what brand starter you have? The answer varies based on those details.
The clicking noise is the giveaway that it's a Lycoming with the Prestolite starter. The clicking noise is the ratchet that allows the drive to spin up after the engine catches without driving the starter to some extreme RPM and blowing it up.

Besides, 6PC has a Comanche. Those airplanes all had Lycomings, and Lycs used that starter setup. Continental always had starters with internal gearing to the engine. They had issues of their own.

You cannot wash the sludge out from beneath the drive. I have tried. That starter needs to come off, come apart, and get cleaned properly. Any sludge not cleaned out, and there will be some, will just cause more trouble sooner or later.
 
My mechanic is coming over to look at it on Wednesday
 
It is very common for the Bendix gears to get grimy and stick in the extended position, or refuse to extend. Once they start doing this, they often get stuck more often. I eventually replaced my starter with a SkyTec starter which is lighter and cranks faster, and not a problem since installation 12+ years ago.
 
Does a starter-failure-to-disengage situation drive electric power into / drain electric power from the ship's electrical system?
 
Does a starter-failure-to-disengage situation drive electric power into / drain electric power from the ship's electrical system?
It won't drive power into it. The Bendix has a clutch in it to prevent the engine driving the starter. But if the starter contactor sticks closed, the starter will keep drawing lots of amperage and will burn itself out. The ammeter will show a big charge, probably on the peg, as the alternator tries to recharge the battery but can't keep up with the massive draw.

We had a nearly-new B&C starter do it on a C150. The starter contactor stuck. The student and instructor noticed nothing until the runup, about three or four minutes after startup, when they noticed the pegged ammeter. The starter got so hot the commutator insulation melted and threw the segments out. End of expensive starter. Caused by an old $25 (at the time) contactor.

Some folks have a starter-engaged light, connected to the starter contactor's output terminal.
 
He came out today to look at it and cleaned it up. We fired it up a couple of times with no issue. He said I should fly it for a while but make sure I am keeping a very close eye on the amp meter and if I see any anomalies we need to look at ordering a new starter but he thinks more than likely I probably did something after I landed when taking the key out or some subtle thing like that he doesn't believe that I was flying around with the starter engaged.
 
He came out today to look at it and cleaned it up. We fired it up a couple of times with no issue. He said I should fly it for a while but make sure I am keeping a very close eye on the amp meter and if I see any anomalies we need to look at ordering a new starter but he thinks more than likely I probably did something after I landed when taking the key out or some subtle thing like that he doesn't believe that I was flying around with the starter engaged.
"Cleaned it up" how?
If you had been flying with the starter engaged you would have heard it--headset or not. I once had mine stick engaged after startup. Godawful racket and shutdown immediately. I didn't know what had happened but knew it was BAD. A bit of looking around and I saw it. No damage.
 
"Cleaned it up" how?
If you had been flying with the starter engaged you would have heard it--headset or not. I once had mine stick engaged after startup. Godawful racket and shutdown immediately. I didn't know what had happened but knew it was BAD. A bit of looking around and I saw it. No damage.
Sprayed 2 different chemicals on it. I think one was a cleaner and the other a lubricant.
 
In case you don't know, "Bogert Aviation" sells STC copper cables that would probably improve your starting.

I just installed the Bogert cables in my Cherokee. They're a bit pricey but worth it IMO. The improvement in starting is unbelievable. The Bogert kit enables compliance with Piper Service Bulletin 836A which seems like it affects nearly every Piper model out there.

Piper Service Bulletin 836A

Bogert Aviation
 
He did confirm it looks like I have aluminum cables so I'm going to order the copper ones
 
I think it's virtually impossible for the starter to remain engaged on a running engine and if so there would be some major racket before substantial destruction. I'm not sure what the gear ratio is but probably at least 10:1 so at 2400 rpm the little stater pinion would have to spin at 24,000 rpm. That wouldn't last for long if it even made it that far.
 
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