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Broken Starter!!!

macrafic

Well Known Member
On only my 3rd flight (probably around my 8th start overall), my SkyTec 149-NL starter literally broke. The housing at the front of the starter that contains the pinion gear which meshes up with the aircraft flywheel/ring gear), broke right off at the two side bolts, allowing the bottom of the housing to fall to the bottom of my cowl and the two gears to separate.

Skytec is willing to work with me on this (good, especially since the starter has been sitting on the engine since Aerosport built it and is, by Skytec definition, out of warranty based on time of installation). However, they are not wanting to warrant a new 149-NL, since they are convinced a kickback occurred due to my lighweight Catto prop on my Lycoming IO-360-M engine. Skytec wants me to consider an HET E-Drive starter.

Both my PMags are at the latest version with the jumper specified by Emag for lightweight props.

Questions:
- Are those of you with Catto props and PMags running the 149-NL starter? It has been my impression (right or wrong) that it is the most common combination?
- Has anybody installed a HET E-Drive starter from Skytec? If so, were modifcations needed to the mounting/cowl/etc or was it a direct replacement?

BTW, I have also sent an inquiry to Brad at EMag to see what they have to say about kickback.
 
A broken starter casing is typically associated with kickback during starting. Did that occur? Hard to miss.

I have a 149NL with a lightweight whirlwind prop. After several kickback events I retarded the timing by about 1.5 teeth on the ring gear, and dont have that problem any more. Helped lower my CHTs as well, but thats a different thread.... Note that if you dont get it started on first attempt for whatever reason, the delay that is programmed into the firing of the pmags is no longer in effect, so you are more likely to have a kickback on subsequent start attempts unless you cycle them off and back on again. The prop rotation can get slower as the battery power decays, exacerbating the problem.

erich
 
Chances are the two screws were loose or pulled. look around here on VAF and you will find many posts like this: http://www.vansairforce.com/community/showthread.php?t=140632
My first one broke in a similar manner, and I’ve had 3 replaced for free from Skytec even beyond warranty. This last one seems to be holding and I did note it was a different design.
I have been wondering if Hartzel would give as good of c/s as the original company.
Tim Andres
Edit: And to clarify, mine broke as a result of the screws being loose.
 
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On only my 3rd flight (probably around my 8th start overall), my SkyTec 149-NL starter literally broke.... they are not wanting to warrant a new 149-NL, since they are convinced a kickback occurred due to my lighweight Catto prop on my Lycoming IO-360-M engine.

Time out.

You have a 149NL, or a 149LS?

The NL has a shear pin. In theory, you can't break one with a kickback.

Early LS starters tended to break the nose case if it got kicked.
 
NL starter failures...

I have had 3 NL starters rip themselves apart... never had the shear pin do its thing to save the casting though.

The replacements have shown small incremental upgrades.
 
However, they are not wanting to warrant a new 149-NL, since they are convinced a kickback occurred due to my lighweight Catto prop on my Lycoming IO-360-M engine. Skytec wants me to consider an HET E-Drive starter.

Both my PMags are at the latest version with the jumper specified by Emag for lightweight props.

BTW, I have also sent an inquiry to Brad at EMag to see what they have to say about kickback.

Why does Skytec think lightweight props can cause kickback?

The only way you can get kickback is if the ignition fires too far before TDC.
 
I have the SkyTec 149-NL starter with Catto 3 blade NLE but also have a 20 lb plate from Saber to help with CG (which it does). I think the extra weight on the prop helps avoid the kick-back issue.

Sounds to me like SkyTec is doing what any MFG would do with a product that is out of warranty, including B&C. If they give you a discount on the other starter, I'd call that good customer service.
 
I just recently broke a Skytec 149-NL starter while experiencing a kickback on the second start attempt. I was discussing my kickbacks with Brad and thought that whenever the RPM is below 200 the timing is retarded to 4 deg ATC with the newer firmware.
So very interesting is what Erich said in post #2 - that on subsequent start attempts the firing delay is no longer in effect not cycling the ignition power.
Can anybody confirm this ?? This would explain my kickbacks.
 
Mine broke off soon after phase 1 was complete and did not suspect a kick back issue (slick mag). Skytech replaced it under warranty and said that they had some issues with the casting and since they have changed it. The replacement start has worked for over 600 hours with no issues.
 
Did you confirm that this was a kickback event?

I agree re: kickbacks, maybe were jumping to conclusions here. Check your Pmag timing, if it?s correct take a close look at the starter assembly, if you find black aluminum oxide residue between the parts, there?s a good chance the old loose screw issued claimed another victim.

Tim Andres
 
SuperCubDriver;1212019 So very interesting is what Erich said in post #2 - that on subsequent start attempts the firing delay is no longer in effect not cycling the ignition power. Can anybody confirm this ?? This would explain my kickbacks.[/QUOTE said:
It's possible the firing delay has been removed in recent versions of the Pmag software- check with Brad on that. I know for sure that my kickbacks seemed to always occur after an initial failed start attempt. As a precaution I now temporarily turn off my ignitions for 2nd (or later) start attempts, and switch them back on during starting after a few rotations when the RPMs are up a bit. Between that and the slight retardation of the Pmag timing, I no longer get kickbacks. I don't currently use an EarthX battery, but those that do report substantially higher RPMs during starting, so that should help as well if you are so inclined.

Erich
 
I think I might check this with a timing light. Let the engine start and stop with the RPM above the switchover point of 200 RPM. Then - without cycling the ignition power - let the starter turn the engine over with a timing light pointed to the flywheel marks. When the ignition then fires around 25 BTC then this could cause the kickbacks on subsequent start attempts.
 
Why did they set the switchover point so low?

Would a TDC fire up to 500 rpm be an issue? It would sure make a nice smooth taxi idle, and even more so if you have a wood or composite prop.
 
If software does not re-initialize the timing events after you stop cranking, that's a major oversight.

I wouldn't be risking any more new starters until I got to the bottom of why.

I'll state again- If you are really experiencing kickbacks which are breaking the starters, you better look at the ignition first. Can ONLY be caused by firing the spark too early.
 
Has anybody installed a Skytec HET E-Drive starter from Skytec? If so, were modifcations needed to the throttle body linkage/starter mounting/cowl/etc or was it a direct replacement?

If you have the HET starter, have you had any issues?
 
On only my 3rd flight (probably around my 8th start overall), my SkyTec 149-NL starter literally broke...

...Both my PMags are at the latest version with the jumper specified by Emag for lightweight props...

Inquiring minds continue to want to know- was this breakage preceeded by a kickback? As other have said, a kickback is violent - thus obvious.

Also, was this start event a single try, or did you have multiple attempts? If multiple, did you cycle ignition power between tries?

Also, is Pmag now recommending the jumper as a SOP for managing start events with a light prop?
 
Inquiring minds continue to want to know- was this breakage preceeded by a kickback? As other have said, a kickback is violent - thus obvious.

Also, was this start event a single try, or did you have multiple attempts? If multiple, did you cycle ignition power between tries?

Also, is Pmag now recommending the jumper as a SOP for managing start events with a light prop?

No discernible kickback. Skytec says however that kickbacks can occur in a split second and would not necessarily be noticeable.

This was a second start attempt. I stopped the first start purposefully to take care of some other unexpected task (bug in the cockpit landed on my ear - probably Asian beetle. They are crazy thick here!)

Pmag is recommending the version 40 upgrade. Also recommending the jumper to move firing to 4 degrees after TDC. Something like that; won?t swear to the exact numbers. Don?t have access to my documentation right now.
 
No discernable kickback is interesting. Ive had a few with Pmags and it was like someone hit the prop with a sledgehammer. Never actually broke anything though.

AFAIK, The jumper is only to shift the overall advance curve to the left. It does not alter the start timing (or it didnt in the past). The Pmag has an ATDC setting on the initial start attempt, but subsequent start attempts go back to normal timing. That's why you have to cycle ignition power between start attempts. This differs from CPI, for example where the start timing is RPM dependant. Does not matter how many times you stab the starter, the timing will go to your retard value, just like a car. No possibility of a kickback.
 
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I have the SkyTec 149-NL starter with Catto 3 blade NLE but also have a 20 lb plate from Saber to help with CG (which it does). I think the extra weight on the prop helps avoid the kick-back issue.

Sounds to me like SkyTec is doing what any MFG would do with a product that is out of warranty, including B&C. If they give you a discount on the other starter, I'd call that good customer service.

I also have the Saber crush plate. Question for you. When you stop your engine (via mixture), does it stop IMMEDIATELY! And I am talking about RIGHT NOW! Prop probably does not take 2 turns. Almost like a Rotax powered aircraft.
 
Broke NL149 Sky Tec Starter this morning

I experienced a kickback this morning and broke the nose off my Skytec NL-149. I have 8.7 compression Lycoming, Hartzell BA prop, two pmags, and timing set 1/2 tooth ATDC. Guess 1/2 tooth wasn't enough. This was the initial start and I have version 40 software on the PMags. It shouldn't have had any kickback. That heavy prop didn't help this time either. Starter is 1 year old with maybe 50 or so starts over the year. Battery is the Earthx so the amps are there.

I just gave away a new lightweight skytec. :(

Not sure which one to try now. Aircraft Spruce has several types in stock. My NL149 weight was right at 9.5lb so maybe I'll try the flyweight this time at 6.5lb and go a full two teeth ATDC on the PMAG timing.
 
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So this is strange on two fronts: First, the Pmag is not supposed to kick back. Second, the NL is supposed to shear the pin before it breaks the nose.

Strange and disturbing...
 
The Pmag has an ATDC setting on the initial start attempt, but subsequent start attempts go back to normal timing. That's why you have to cycle ignition power between start attempts.

Michael - forgive my ignorance... I thought P-Mag timing for start was controlled by RPM. This is the first I've heard of ATDC timing going away after the first start attempt.

I'm not trying to call your bluff, just trying to ensure I fully understand how to operate this ignition. Our aircraft is equipped with a slick impulse on left, V.40 p-mag on right side of our O-360.

Would you mind expanding on this topic, please? I'm particularly interested in how the p-mag senses that a start attempt has occurred. Is it ANY displacement of the internal timing gears after initial power-on? Is it RPM exceeding some low threshold value, with this value never being checked again after the first cranking event?

Thanks for so patiently sharing your knowledge.
 
Starter

Rich, I had good luck with these folks when they were in Texas. Now that They were bought out and moved to Alabama, I've had terrible support. 4 starters in 5 years with slick mags. Sooner or later you have to go B & C.

Glad you and Cindy are flying.
 
I asked Brad about the start timing. He said no need to reset the ignition power. Anytime the RPM drops below 200 the timing reverts to the start position which should be 4 deg ATDC with firmware 40.
Still wondering why the kickbacks happen when there is no spark before TDC.
 
OK, I have to admit I was pretty alarmed by some of the info shared above. So much so that I contacted Brad at EMagAir. I've copied his response below.

I believe this answer sets the record straight with respect to P-Mags and cranking.

I believe this answer also provides us with some additional information which may help some folks with special-use cases where they may want the engine to turn over a couple of revolutions before firing.

Whew! I feel a lot better now. I'll hit the "START" button knowing the P-Mag will retard the ignition to an ATDC condition each and every time I crank.

=================
E-MAGs automatically retard for start-up firing any time (as long as often as needed) the engine is below 200 RPM.

There is a different feature (run mode start delay) that delays firing until the engine has passed "X" number (customer set) of revolutions. That is a different feature with a different function. That feature has a one-time reset requirement, and is likely what's being confused with our starting routine. That feature is very seldom used and is not needed with proper/recommended starting technique.

In addition to the automatic 4 degree starting lag (V40 and after), each E-MAGs has a five (5) strike sequence during start-up. If installed on both sides, we provide 20 long reach strikes per rev vs. one strike from an impulse mag.
=================
 
Michael - forgive my ignorance... I thought P-Mag timing for start was controlled by RPM. This is the first I've heard of ATDC timing going away after the first start attempt...

I was an early adopter of Pmags (since 2005), and that's how it was back in the day... It may have changed with recent releases.

However, we have a kickback event and broken starter with V.40... Not supposed to happen.
 
Why NL?

So I drove to Spruce, got the new type of autoclutch Sky Tec starter, drove home and now I remembered why I went with The NL149 to begin with...... it's the only one that fits my horiziontal induction snorkel arrangement. So I get to either get another NL149 or modify the snorkel to fit multiple starters.

And I thought that today was going to be an easy fix....

By the way, I've been very happy with Pmag ignition. I only have a pad mounted alternator that has limited output so my ignition options are limited. These types of setbacks are not as bad as they seem as it gives me opportunity to see the different type of failure modes and make changes to minimize them in the future. The new starter autoclutch option was looking promising.
 
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I experienced a kickback this morning and broke the nose off my Skytec NL-149....Starter is 1 year old with maybe 50 or so starts over the year.

Call 'em. Ask for a new one. Maybe they say yes, maybe no, but they need the feedback in any case.
 
#metoo

Mine gave out at SunNFun last year after 11 years and 1050 hrs. Cracked at the mounting boss. It took a while but some friends hand propped me and I flew home to mid GA.
 
I broke a SkyTec on my RV-8 with IO-360 and Slick Mags. My timing was good.

After doing some research decided to go with a B&C starter. The quality is impressive and the performance is excellent. Starts first try.
 
My sky tec XLT starter just crapped out as well, though strange failure. 66.7 hours on it, about 85 starts. Last few were slow to turn and getting slower, bus volts dropping more and more until only 1/2 blade and bus going to 6 volts.

Looked like classic bad battery, replaced no change. Turns out I measured 286 ohms across power in on starter and nose gear. Worked fine, no load if course sitting on floor. But it was shorting out when gear engaged ring gear so 1/2 blade stop and shorting all battery power.

2 years and 2 months old. Hartzell gave the ok to send it back, will see if they warranty. I would hope do with so few cycles.
 
Sky Tech Followup

Talked with Sky Tech and they are going to warranty the starter. My neighbor let me borrow his lightweight sky tech starter in the meantime. I re-timed the dual Pmags so that it fires two teeth ATDC which is in the neighborhood of 4.8 degrees ATDC. I run the A curve currently. Didn't want another kickback to break my neighbors starter. Starts and runs a lot smoother but it appears that I lost 3 mph on the top end. CHT's seem to be cooler also. I'm guessing that if the initial PMag setting is 28 degrees BTDC, I am about 23.1 degrees BTDC now at idle. Given the system variation in timing, I am hoping that 23.1 degrees is nicer to my motor.


Call 'em. Ask for a new one. Maybe they say yes, maybe no, but they need the feedback in any case.
 
So I drove to Spruce, got the new type of autoclutch Sky Tec starter, drove home and now I remembered why I went with The NL149 to begin with...... it's the only one that fits my horiziontal induction snorkel arrangement. So I get to either get another NL149 or modify the snorkel to fit multiple starters.

And I thought that today was going to be an easy fix....

By the way, I've been very happy with Pmag ignition. I only have a pad mounted alternator that has limited output so my ignition options are limited. These types of setbacks are not as bad as they seem as it gives me opportunity to see the different type of failure modes and make changes to minimize them in the future. The new starter autoclutch option was looking promising.

I just went through the same process today. Broken NL starter. Upgraded to the E-Drive starter, but the wiring is in an odd place and interferes with the mixture linkage on the throttle body and it is too close to the top of the throttle body for my, and Hartzell's, comfort. Got measurements for the HT starter and there is no way to fit that in without major modification to my horizontal induction air box. Got the measurements for the B&C starter and it also would require major modification to the air box.

So, like you, I am stuck with the NL starter. Will give it one more try. If it breaks again, fiberglass work will be in the cards!
 
I just went through the same process today. Broken NL starter. Upgraded to the E-Drive starter, but the wiring is in an odd place and interferes with the mixture linkage on the throttle body and it is too close to the top of the throttle body for my, and Hartzell's, comfort. Got measurements for the HT starter and there is no way to fit that in without major modification to my horizontal induction air box. Got the measurements for the B&C starter and it also would require major modification to the air box.

So, like you, I am stuck with the NL starter. Will give it one more try. If it breaks again, fiberglass work will be in the cards!

What ignition system are you using?
 
Fiberglass , uggggg

Rich,
Initially I bought the HT starter to replace my NL. I even cut my snorkel so it would fit but after all the rework, I didn't like how much restriction in airflow there was. So, I removed the HT and took it back, then cut out the recess I made in my poor snorkel, then glassed it back the way it was. That being said, the standard lightweight Sky Tech starter fits perfect. When the NL comes back from Skytech, it should fit also. The HT however will not but that's ok.


I just went through the same process today. Broken NL starter. Upgraded to the E-Drive starter, but the wiring is in an odd place and interferes with the mixture linkage on the throttle body and it is too close to the top of the throttle body for my, and Hartzell's, comfort. Got measurements for the HT starter and there is no way to fit that in without major modification to my horizontal induction air box. Got the measurements for the B&C starter and it also would require major modification to the air box.

So, like you, I am stuck with the NL starter. Will give it one more try. If it breaks again, fiberglass work will be in the cards!
 
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