Starter or Battery or ?

RCT44

RCT44

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Anyone here have an issue with the standard starter that comes with super decathlon? For a frame of reference I have a 2005 with about 530 hours on it. Meticulously maintained by the previous owner who purchased a new battery two years ago for it. He only put about 40 hours on the plane over the course of four years. I have about 30 hours on the plane since I purchased it two months ago. Never had an issue until this past week when the plane started for me, I taxiied it to get fuel. When I went to start it back up the starter felt very weak as if it was not getting enough juice to even turn over the prop. It started up once we jumped it with a car running next to it and felt like it was stronger than ever. I called my local A and P who helped me into a new battery, installed it and said I was good to go. I started playing today and flew two hours south until I stopped to get fuel. When I went to start it back up I had the same issue again. It would not start up and felt like it did not have enough power to throw the propeller over. There is a chance that I performed a cold start when it should have been a hot start. after shutting down and resting a few 10 minute intervals and retrying I realized I was screwed. It was starting to get dark and I was getting nervous. Luckily, a gentleman was coming to the airport to get fuel for his truck of all things. He asked if I need a jump to which I said yes. Once we hooked up the cables the engine started like it had the strength of 100 engines and have no issue running and taking me to my next destination.

If anyone has any ideas I think my next guess is to get a new starter potentially one with higher compression, something my instructor suggested.
 
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Definitely sounds like alternator isn’t charging. Be sure the belt is tight and in good condition. Make sure all the electrical leads to the alternator are tight and in good condition. If all of that checks out ok, then the alternator will probably have to be pulled to be tested.

Pete
 
I used to start with the cheapest component, and just replace stuff. But now I have a diagnostic sequence, mostly done with the engine off. Works every time - usually it is a poorly crimped wire on the regulator.

But yeah - the minute my Prestolyte gives up I am getting a B&C.
 
Is B&C a type of starter? What’s considered the best? My instructor said I need a high compression starter which would be an STC…
 
It sounds like your existing starter can do the job when it has enough amps to turn it. And it sounds like the connections to the starter are ok since it'll turn when the source powering it is strong enough. Since the battery is new and since it works sometimes, let's assume it's not the problem.

If the battery isn't the problem, and if the starter isn't the problem, it's possible like @pfcastine said that the alternator isn't charging the battery. The battery works, you fly around a little, and then it doesn't. It's possible that the plane is being powered by the battery during flight and that the alternator isn't charging it when the engine is running. The quick fix might be the belt is too loose or one of the connections related to the alternator (could be at the master switch, at the bus where the alternator feeds into the electrical system, or one of the connections at the alternator itself) isn't making good enough contact. If those are all ok, then the alternator might be bad.

Like @Bob Turner said, it might be the voltage regulator or the wiring associated with it. If the regulator isn't allowing the alternator to put out enough voltage then the battery won't charge. The battery is twelve volts, the alternator should be putting out about 14 to keep the battery charging. If the plane has a voltmeter, you can run the engine and look to see what the electrical system is running at. If it's more than twelve by a needle width or two then the alternator is probably making the voltage. If it's stuck at twelve (or less) then the electrical system is running off the battery.

Your ammeter should also show a positive indication when the engine is running showing that there is current flowing to the battery. An indication at zero isn't necessarily bad if the battery is fully charged but a negative indication of any amount is bad news when the engine is running at more than idle. A generator equipped engine always needs to be at higher RPM to show the battery charging, just to round out the conversation.

Hope that helps! Don't buy a new starter just yet!
 
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Sounds just like my alternator did when it went bad.

You draw a lot of current from the battery starting the engine. Normally the alternator charges it back up within about a minute after starting. If the alternator does not work, the battery does not get recharged. After a few starts, the battery gets run down and can't turn over the engine. When you jump start it, you are actually recharging the battery while the jumper cables are attached. So now the battery has some charge and starts again. A few more starts and it gets run down again. You can go on for weeks like this. And if the battery sits at a state of discharge for long periods, you kill the cells and the battery goes bad.

Could be the voltage regulator too, but those are solid state, while alternators have mechanical parts like brushes and belts that wear out over time.

My Super D has 2500 hours with a normal OEM starter. Nothing fancy or extra powerful needed. Just sufficient current from a fully charged battery.
 
Thanks guys. Here is a photo of the ammeter while flying after being jumped. It’s always right around this area during flight and taxi. I wish I knew what it was without replacing both.
My mechanic said if the ammeter shows what mine is it can’t be the alternator. Does that make sense to y’all?
 

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Assuming all your electrical connections are tight and bright. Everything works fine when your boosting the planes battery. That means a weak battery for some reason. After you get the plane started does the ammeter show a large positive deflection showing a high charge rate?
What you need is a voltmeter to monitor ships power. A simple checker can be had in the Aviation Isle of an auto parts store that plugs into a cigarette lighter. If your ammeter says the alternator is charging one of two things might be happening: you either have a bad starter solenoid or a bad battery. And I know the battery is only two years old but I've seen batteries fault at 6 months (Gill).
First and cheapest: hook a voltmeter to your electrical system. Run the engine and look for proper voltage (13.8-14.2). If the voltage is OK turn on everything in the plane, lights radios,etc. and see if the voltage stays constant.
If it does your alternator is doing its job.
Next find a battery you can swap for yours. See if the charging indications change...a battery with a bad cell will not allow a full charge from the charging system...it will look like its charging but will lack any capacity. This is where watching the voltage during starting helps, if the battery shows good standing voltage but the voltage tanks when you put a big load on it the battery is on its way out.
The other potential trouble spot is the starter solenoid...I don't know when the switch was made from the old "can" style solenoids to the new type "disk" type but the newer solenoids don't tolerate low voltage (high amperage) starting for many cycles...the contacts burn up and when they do they impede the electrical flow to the starter itself.
Hope this helps;
Chris
 
Hiperbiper said:
Assuming all your electrical connections are tight and bright. Everything works fine when your boosting the planes battery. That means a weak battery for some reason. After you get the plane started does the ammeter show a large positive deflection showing a high charge rate?
What you need is a voltmeter to monitor ships power. A simple checker can be had in the Aviation Isle of an auto parts store that plugs into a cigarette lighter. If your ammeter says the alternator is charging one of two things might be happening: you either have a bad starter solenoid or a bad battery. And I know the battery is only two years old but I've seen batteries fault at 6 months (Gill).
First and cheapest: hook a voltmeter to your electrical system. Run the engine and look for proper voltage (13.8-14.2). If the voltage is OK turn on everything in the plane, lights radios,etc. and see if the voltage stays constant.
If it does your alternator is doing its job.
Next find a battery you can swap for yours. See if the charging indications change...a battery with a bad cell will not allow a full charge from the charging system...it will look like its charging but will lack any capacity. This is where watching the voltage during starting helps, if the battery shows good standing voltage but the voltage tanks when you put a big load on it the battery is on its way out.
The other potential trouble spot is the starter solenoid...I don't know when the switch was made from the old "can" style solenoids to the new type "disk" type but the newer solenoids don't tolerate low voltage (high amperage) starting for many cycles...the contacts burn up and when they do they impede the electrical flow to the starter itself.
Hope this helps;
Chris
Click to expand...

chris - super helpful. Thank you and everyone else on this thread. The battery is brand new as of 4 days ago so I guess we can take that out of the equation, right? I had a new one put in by AP this past week.
 
If it will start go fly it for awhile and taxi back to your hangar. In hopes that it will give you trouble, try to restart it. If it won't turn over, put it on a charger over night. If it starts nicely in the morning, you have just learned that the battery takes a charge and the starter works just fine. Look at the alternator and voltage regulator (and associated wiring) for the trouble.

Good luck
 
Watch your ammeter closely when you start the engine. When the engine starts, it should read at least +10 or +15 amps initially, then drop down to just above zero amps after about 30 seconds. If it does that, then yes the alternator and voltage regulator are functioning correctly.
 
Big Ed said:
Watch your ammeter closely when you start the engine. When the engine starts, it should read at least +10 or +15 amps initially, then drop down to just above zero amps after about 30 seconds. If it does that, then yes the alternator and voltage regulator are functioning correctly.
Click to expand...

That is happening. So if it shows that on the ammeter it must be something else. :-/
 
With a low battery after jumpstarting, you might expect the amp meter to show +10 or so for quite some time while it recharges the battery, then slowly returns closer to the 0.
 
Ok. Alternator is alternating. Battery is new.
Old time trick (if no voltmeter is available)...
When you know the battery is hot but it's not starting turn on the landing light. Have someone watch it. Hit the key.
Light dims out or goes out completely= starter bad.
Lights don't dim= starter solenoid bad.
Chris
 
Yes, but isn't that solenoid in series when you jump start?
Agree on the voltmeter. My old 295 handheld has a voltmeter, as does the Becker com (its best feature . . .).
I am putting the cheap plastic voltmeters in all the Cubs, and maybe the Decathlon. What a difference!

I forgot to look at my diagnostic. It is available on-line from Zigtronics or something like that. Two different types - Cubs and Cessna/ Beech. I want to say type A & B. Where is Web when we need him?
 
Bob Turner said:
Yes, but isn't that solenoid in series when you jump start?
Agree on the voltmeter. My old 295 handheld has a voltmeter, as does the Becker com (its best feature . . .).
I am putting the cheap plastic voltmeters in all the Cubs, and maybe the Decathlon. What a difference!

I forgot to look at my diagnostic. It is available on-line from Zigtronics or something like that. Two different types - Cubs and Cessna/ Beech. I want to say type A & B. Where is Web when we need him?
Click to expand...
The difference in a jump start is 2 batteries in parallel (if the one being jumped has any power at all).
The difference in the troubleshooting trees are whether the charging system is type A or type B. Every alternator needs power and ground (F1 & F2) supplied to it to produce charging voltage. The difference in the two is HOW the field is controlled...in the type A system the alternator has power supplied to it thru the buss/alternator CB-Switch full time. The field output voltage is controlled by the regulator turning the GROUND on and off. In the type B system the alternator is grounded all the time and the field voltage is controlled by the regulator turning the POWER on and off.
Needless to say, before troubleshooting the charging system you need to know which system you have.
The Magic smoke inside either system is the same...
Chris
 
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Guys - after a lot of research and help from everyone on this thread, my AP ran a few more tests and we decided that the older B&C starter was done. I ended up purchasing a new starter. As you can see from the video, it is seriously throwing the blade around now. Thanks for all the help everyone.

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New video · Friday, Jan 14, 2022 🎬

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