Skytec Starters on IO-550 run with Synthetic Blend Oils - A bad combination!

[GeorgePerry]

I wanted to summarize an unpleasant and expensive experience I recently had that has been discussed in a few different places and summarize the crux of the issue one thread.  This was my experience - Others milage might vary.

Bottom line up front.  If you have an IO-550 equipped Mooney I would strongly suggest NOT installing a skytec ST4 starter - Here's why.

The lightweight replacement starters don't have the torque to correctly engage the starter adaptor and over time the starter adaptor will start to slip and need to be replaced.  Synthetic oils such as Aeroshell & Exxon Mobil Elite seem to accelerate this process and cause premature wear to starter adaptors (a very expensive part $1.5-3.5K AMU depending on reconditioned or new).  

After my original starter adaptor went bad, I thought it would be a good time to put on a Skytec ST4 along with a brand new starter adaptor.  Thought I'd save some weight and get the great starting power that I was used to from the Skytec I installed on my Mooney M20F w an IO-360.  Boy was I wrong.  The ST4 that goes with the IO-550 was not up to the job.  The Skytec ST4 turned the engine over noticeably slower than the stock energizer starter and sounded like a bag of rocks when it was engaged.  Even though I was never really happy with the result, since the work was done, I figured I'd leave well enough alone....or so I thought.

In less than 10 months with the pitifully weak skytec installed, my brand new $3.5K starter adaptor started slipping and needed to be replaced...ouch!  After looking around and doing some research I found that several other IO-550 continental owners had similar experiences.  Here's a link to another thread and a webinar by Mike Busch that talks about engine oil  that talks about the problems with synthetics.  Skip ahead to 38 minutes for the summary.

I just switched back to the stock energizer starter and replaced my oil with Phillips X/C 20W-50.  Results were GOOD, IMMEDIATE and NOTICEABLE.  Stock starter spins the prop incredibly well and without any grinding mechanical noises that the Skytec Customer service reps told me was "normal" with their starter.  This seems like a case that the factory got it right from the start, even though the stock starter is somewhat heavy.   Lightweight aftermarket starter options might seem attractive but over the "not so long run" can empty several AMU's from your wallet

I want to be clear, for IO-360 engines the skytec starters seem to be a real benefit. But on the big bore IO-550 they aren't up to the job.  

Summary:  If you have an IO-550 stick with the stock starter and don't swap out for a skytec.  If you fly often, skip the synthetics and just run a normal ash-less dispersant oil.  Hope this helps someone avoid the same issue I went through.  

 

 

 

[Guest]

This problem does not really exist in other airframe/engine combinations with traditional heavy old style starter motors.  It effects engines with small light weight starters.  The weight penalty is relatively small to go back to a traditional starter.  

I'm not really sure that oil plays a very large role, engines have run on Aeroshell 15W50 for decades.

Clarence

[philiplane]

I have an IO-550 in the shop for other repairs. It has a worn starter adapter shaft, even though the plane has been running Phillips 20w50XC so you can't blame synthetic oil or anti-scuff additives for the wear. This adapter has less than 500 hours since NEW. Continental is covering it under warranty.

[N601RX]

Seems like there is a lot to be said for an old fashion Ring Gear around the OD of the flywheel. 

[KSMooniac]

3 minutes ago, N601RX said:

Seems like there is a lot to be said for an old fashion Ring Gear around the OD of the flywheel. 

The Continental design sure seems like a solution looking for a problem that didn't need solving...

[Cruiser]

5 hours ago, philiplane said:

I have an IO-550 in the shop for other repairs. It has a worn starter adapter shaft, even though the plane has been running Phillips 20w50XC so you can't blame synthetic oil or anti-scuff additives for the wear. This adapter has less than 500 hours since NEW. Continental is covering it under warranty.

Which starter was on this engine?

[Guest]

1 hour ago, KSMooniac said:

The Continental design sure seems like a solution looking for a problem that didn't need solving...

It's a problem related to "high performances" singles with poor useful load, whose manufacturerers chose a light weight starter.  We seldom see this problem on Cessna twins, or Beech singles or twins.

Clarence

[philiplane]

It's not a starter problem. The shaft had to have been made undersize by mistake since it is not worn in the manner that is caused by a starter failing to release.

It does have a C24ST5 starter which releases the spring instantly, as does the C24ST3 predecessor to this starter. The only lightweight starter with a slow release is the Iskra starter that appeared in 2006 and was replaced by the Skytec designs in 2011. But there are still many Iskra starters in service.

 

[KSMooniac]

I was referring more to the design with the starter adapter/clutch thingy vs. the tried-and-true simple flywheel with teeth + conventional starter.  

There are quite few threads on Beechtalk about this problem on Bonanzas (and some Barons) and many folks report problems with the synthetic oils.  I haven't paid attention close enough to identify how many were using a LW starter vs. regular, though.

[philiplane]

synthetic oils tend to last longer and have higher shear strength, which would be beneficial to the adapter design. If a starter doesn't release, and thereby holds the spring under tension, then you would prefer a slippery oil to prevent heat damage to the shaft. A straight mineral oil would be worse.

[KSMooniac]

Here is a quote I just lifted from Beechtalk on the subject...there is some very pertinent info on synthetic oil + TCM starter adapters in the middle:

 

Here is the response that I sent to the ABS when I saw this. I have not seen it published.

Thank you for the opportunity to comment on Bob Ripley’s misunderstandings about Camguard. He states that if you use Aeroshell W100Plus there is no reason to use Camguard as the “corrosion inhibitor” is already in the Shell product. As I will explain, this is incorrect and I will also explain a couple of related issues. 

The Aeroshell W100Plus (and 15W-50) contains 0.05% of a ferrous metal rust inhibitor, 0.05% of a yellow metal (copper) corrosion inhibitor and 0.9% of a butylated/ isopropylated triphenyl phosphate, b-TPP, antiscuff/antiwear (LW-16702) to meet the Lycoming SB 446E and SI 1409C for scuffing.

Camguard contains 25 times the level of rust inhibitor than the Aeroshell products, and demonstrates vastly superior rust protection. Shell cannot increase the level of rust inhibitor in their oil because the type of chemistry (acid ester) they are using causes bearing corrosion problems at increased concentration. Camguard uses different chemistry. So if you use Camguard WITH the Aeroshell W100Plus you end up with 26 times (1x from the Plus and 25X from the Camguard) the level of rust inhibitor over the W100 alone. I recommend using AeroShell W100 or Phillips 20W-50 oils as they are cheaper than the W100Plus and they are good platforms for Camguard. 

There are two other issues concerning the Plus and the 15W-50. The b-TPP, in the Aeroshell and Lycoming LW-16702, is a good antiwear but it is a very good friction modifier. This is very important when using these products in Continental engines utilizing starter adapters. A new or “in spec” starter adapter will not have a problem with this compound, however, a worn or marginal adapter will often slip (starter turning but prop not turning) when using oils with this additive. It is not uncommon to have an older adapter start slipping when changing over to the Shell products for the first time. If an adapter starts slipping, changing the oil back to an unadditized oil (w100) will often stop the slipping. However, this is usually only temporary as slipping causes changes to the starter adapter sleeve friction fit and the adapter will eventually need to be serviced. 

I was very careful to not use anything in Camguard that would reduce the friction and cause starter adapter problems. And the anti-wear components in Camguard protect the shaft and spring surfaces from wearing. 

The final issue with the 100Plus is the degradation of the b-TPP itself in the engine. It decomposes (through hydrolysis) in the presence of water, heat and metal all of which are found in abundance in an engine. When Shell changed to b-TTP, from methylated triphenyl phosphate, which is better known as TCP, because of neurotoxicity issues, people reported copper in their oil analysis went from 5 to 250ppm. This increase was due to the breakdown of the butylated triphenyl phosphate to an oil soluble form of phosphoric acid. 

Shell responded to this problem not by yanking the offending agent out of their oil but rather by adding a good slug of copper inhibitor. This protected the copper but left the acids in place to attack other things. The seals in the engine are susceptible to acid attack, with the silicone seals the most sensitive. With the Shell 100Plus, the silicon levels are usually higher in oil analysis and the air filter most often gets the blame. The good news is that the seal conditioners in Camguard mitigate this problem altogether. So in actuality, you SHOULD use Camguard with AeroShell W100PLUS, 15W-50 and Lycoming LW-16702 for the multiple reasons just described. 

If Mr. Ripley or any other people on your staff have any technical questions about Camguard, lubricants or fuels they should feel free to contact me.

Regards,

Ed

Edward Kollin
Technical Director 
Aircraft Specialties Lubricants

[GeorgePerry]

Foot note to this story...I spoke with the folks at skytec and let them know I wasn't happy with the substandard performance of the ST4 and its inability to turn the engine over as good as the stock starter.  "Initially" the CSR said, no problem, since it's within the warranty time period, send it back and they'll be happy to issue a core refund.

She issued me an RA # and I put the starter in the mail.  After a few days, one of the principles at Skytec called me and said they would not issue me a core refund b/c they couldn't find the paperwork from when I purchased it. I let them know I purchased it directly from them about ten months ago, but mysteriously they couldn't locate any record of the transaction, even though they had the starter with the serial number.  Result was the gentleman said they would not issue a core refund.  

No big deal..its a few hundred bucks is not worth quibbling over.  I told him I understood and not to worry about it.  He then asked why I was returning the starter.  I explained I was never happy with it and the ST4's was not up to the task of starting an IO-550.  The stock performs much better and that's why I reinstalled it.  

That must have struck a nerve.  He responded with hostility and belligerence.   Shouted at me over the phone and said they had thousands of skytec starters on IO-550's.  I responded calmly and respectfully and said, "while that might be the case, my experience is that the product wasn't up to the job" and "my comments were meant as constructive customer feedback, nothing more."  Then he shouted "your not getting your money back" to which I responded, I don't care about the money nor do I want the starter. I am happy for you to keep it.

I suppose this is just icing on the cake...If I could roll the clock back I'd:  1. stay away from synthetics, 2. keep my stock starter, and 3. use Niagara Air Parts for a reconditioned starter adaptor....Oh yea and I definitely wouldn't install a skytec starter onto an IO-550.

[jetdriven]

Excellent customer service, Skytec.  Just a question, were these the retards in Alabama that just bought Skytec that you talked to, or the one who just sold out?

also, do the community a favor, George, and post this on BT and FB Mooney pilots. 

Edited July 10, 2016 by jetdriven

[Guest]

I've got a shelf of low time ST3 and ST5 starters that they don't want back at even core values.  They may be fine on 360's but don't perform well on 550's.

Clarence

[StevenL757]

On 7/10/2016 at 5:18 PM, GeorgePerry said:

Foot note to this story...I spoke with the folks at skytec and let them know I wasn't happy with the substandard performance of the ST4 and its inability to turn the engine over as good as the stock starter.  "Initially" the CSR said, no problem, since it's within the warranty time period, send it back and they'll be happy to issue a core refund.

She issued me an RA # and I put the starter in the mail.  After a few days, one of the principles at Skytec called me and said they would not issue me a core refund b/c they couldn't find the paperwork from when I purchased it. I let them know I purchased it directly from them about ten months ago, but mysteriously they couldn't locate any record of the transaction, even though they had the starter with the serial number.  Result was the gentleman said they would not issue a core refund.  

No big deal..its a few hundred bucks is not worth quibbling over.  I told him I understood and not to worry about it.  He then asked why I was returning the starter.  I explained I was never happy with it and the ST4's was not up to the task of starting an IO-550.  The stock performs much better and that's why I reinstalled it.  

That must have struck a nerve.  He responded with hostility and belligerence.   Shouted at me over the phone and said they had thousands of skytec starters on IO-550's.  I responded calmly and respectfully and said, "while that might be the case, my experience is that the product wasn't up to the job" and "my comments were meant as constructive customer feedback, nothing more."  Then he shouted "your not getting your money back" to which I responded, I don't care about the money nor do I want the starter. I am happy for you to keep it.

I suppose this is just icing on the cake...If I could roll the clock back I'd:  1. stay away from synthetics, 2. keep my stock starter, and 3. use Niagara Air Parts for a reconditioned starter adaptor....Oh yea and I definitely wouldn't install a skytec starter onto an IO-550.

Took me a few days to get around to reading this, but now that I did...wow.  I'll assume positive intent, in that I'm guessing his reaction isn't shared by the rest of the company, but a reaction like that certainly speaks volumes.  It's blatantly clear who the dignified professional on that phone call was.

Although it's been said before, and to reiterate CMI's position on the topic, SkyTec lightweight starters have no place on IO550 engines...especially those in our Mooneys.  The Energizer starters are far superior, and will cause you far less headache and wasted money than anything SkyTec has to offer.  IMHO, the slight weight savings of a SkyTec will never be enough for me to make the switch.

George, thanks for sharing the experience and "taking one for the team".  I hope anyone considering switching from an Energizer (or other reputable starter) learn from your experiences and stay with what's been proven rock-solid to work properly.

Steve