Sky-tec starter vs Delco Remy starter adjustment and switch

[krines]

Any body got some experience with this starter. Lately I've gotten too much experience hand proping due to my hand pull starter. I've got a C145-2. Steve

[jrenwick]

I have a B&C starter on my O-300-powered Swift -- practically the same as a C145. I've had absolutely no trouble with the B&C starter, and would recommend it. Both B&C and Skytec starters are easier to install at overhaul time, because the shaft your present starter mounts on must be cut off. It can be cut with the engine mounted on the airplane, but it takes time and care.

[blueldr]

Installation of some models of light weight starters do require the grinding off of the starter pinion shaft with a die grinder while installed in the engine.
I would be rather timid when it came to running a high speed abrasive grinding cut off wheel down inside of an active engine. I believe I would prefer to have my standard starter rebuilt. If it was engine overhaul time, I would definitely go with the light weight type.

[GAHorn]

Installation of some models of light weight starters do require the grinding off of the starter pinion shaft with a die grinder while installed in the engine.
I would be rather timid when it came to running a high speed abrasive grinding cut off wheel down inside of an active engine. I believe I would prefer to have my standard starter rebuilt. If it was engine overhaul time, I would definitely go with the light weight type.

I agree with bluElder. I would add that the original starters will still be available in another twenty years. I don't know about these others. The advantages of the B&C and SkyTec are light weight (saves about 10 lbs) and faster spinning during start (not necessary and carries some unique hazards of it's own.) The advantage of the original starters are price and availability. The disadvantage is the already-mentioned weight, and the need to maintain the starter-clutch (something the newer 5-roller clutches relieve somewhat.)

An unexpected benefit to original starter proponents are the increased availability and lowered prices due to convertees selling off their originals. I bought a spare, including clutch, in very good condition for $50 including freight, even tho' I do not expect to need it soon, as I very inexpensivley replaced my starter brushes and bushings for less than $25 in my hangar.

It's a mistake to overlook regular maintenance on our starters. They should be inspected for brush-wear every annual, and they should have new brushes/bushings every 500 hours. (Same for the newer types, also.) Most folks run 'em 'til they fail....and then wonder why it happened.

[krines]

I am a bit of an originality nut and regret having to think of using the Sky tec but I am truely getting tired of maintaining my starter only to have it fail on me when I have landed in a field out in the middle of nowhere. My problems have been mostly with the push button switch not making proper contact. Then when I get that fixed the teeth of the pinion gear are not fully engaged when it fires. I have not yet experienced the clutch problem that is discussed alot. My parking brakes are disconnected for reasons noted in this forum so hand proping when I am alone can be tricky. The last time I had to drag my plane 300 yards through the alfalfa I landed in so I could tie the plane to a fence. The sun was setting and I thought I was going to die from a heart attack dragging that plane to the fence and if that didn't kill me the prop would and I didnt want to think about taking off in the dark, can you say black angus. I live in Montana and the thought of repeating that excersize in the cold does not sound like fun. Maybe you can sense my frustration, I'm starting to think my starter is going to be the death of me. Steve

[Bruce Fenstermacher]

Steve,

it sounds like your problem is the button. Why not fix or replace that. This is the first I've heard of this kind of problem so it must be pretty rare or we'd be talking about it all the time. I've personally been flying in two 170s for more than ten years and have never had this problem and don't expect to because it is just not an issue. And we haven't had clutch problems either. But of course everything wears out so at some point it might happen to us.

I understand your frustration but i wouldn't be so quick to jump to another system which could fail in the same way. The light weight starters would be using a solenoid which can burn and fail as well.

[jrenwick]

If your starter pinion gear isn't fully engaged when the starter starts to turn, then it isn't adjusted correctly. This is important; you may find metal chips in your oil screen if it's not right. I've forgotten where the adjustment specs are -- surely someone else on this forum has the reference. Before you consider a new starter (and I would recommend B&C over Skytec), make sure your present one is set up correctly. This might be your only problem with it.

[GAHorn]

Here's the adjustment (see para. d) and service instructions.

Starter Adjustment clearances.JPG

DelcoRemy Starter Adjust.pdf

By the way...does THIS $9.95 John Deere tractor part look familiar? (Fits JD Model A, B, G, R as well as Models 50, 60, 70. PN 820052)

starter switch.jpg

Post-Script: Here's an even better description of installation and adjustment from the Niagara folks who make the 5-roller clutch:

Niagara Pull Starter Install Insrructions.pdf

[blueldr]

John Renwick,
You mentioned that you prefer the B&C starter over the SkyTec. Have you personally gone into an active engine with a high speed die grinder using an abrasive cut off wheel to grind off the hardened starter pinion shaft? If so, how do you keep the abrasive residue out of the engine----guaraneed? It would only require a very small amount of abrasive residue to wipe out an almost non replaceable crankshaft or camshaft. The only other way to remove the starter pinion shaft is to split the cases.

[jrenwick]

BL, I haven't done it myself, but Dennis Hoffman, also a C170 member, has done it to a couple of his airplanes. I think he used a Dremel tool with a cut-off wheel, and he made cardboard cutouts that he taped around the spindle, and he may have coated them with grease to catch the debris. It has to be done with great care, of course. Dennis is very fastidious around his engines. He put the B&C on his 170 because the old Delco-Remy starter was the source of the last oil leak that he couldn't stop. He made a fixture for the firewall to hold the starter button with a lever over it that he attached to the original starter cable so that he could keep the panel as it was. Cool!

John

[cessna170bdriver]

A mis-adjusted Delco pull starter was the direct cause of my first overhaul; about a teaspoon of metal shards in the oil screen. Fortunately, it was caught early enough that the crankshaft polished out without grinding to undersize. I quickly learned from the manual how to properly adjust the mechanism to ensure full engagement. What I never did get used to was that I could never get the darn thing from leaking oil for more than a few hours at a time. This last overhaul I replaced the Delco starter with a B&C and have not looked back. No regrets.

Miles

[GAHorn]

Sacramento Sky Ranch has some comments about lightweight starters:
http://www.sacskyranch.com/faqstarter.htm

I post this next with some hesitancy, because it is a cut/paste from another discussion-site and it's credibility is therefore unknown, but I can personally report that I've rec'd unfulfilled promises from the company previously.

"SkyTech Starter.
It is very light weight, it turns the engine very fast. However, it does not disengaging very fast.

I called up SkyTech and they have admitted that there is a problem with back EMF keeping the solenoid energized for as much as 6 seconds too long. They say that 1 out of 100 had this problem.

They will fix the starter (and replace the motor if it has become burned out). I will send it to them next day air. They will send it back same day, next day air. They will not pay for the labor to switch the starter. Also, one new wire will have to be added.

What a pain in the butt!

Oh, well, I had to remove the prop anyway because there is a new AD that requires me to change my prop bolts at overhaul. When my engine was done the bolts had not come in yet so I opted to do that another time.



--------------------------------------------------------------------------------


My mechanic has my starter back from the factory.

The current fix is to add a new wire.

There is now a new terminal on the starter. The power for the solenoid (permanent magnet starter with a solenoid to move the Bendix gear) has been separated from the power for the motor (because back EMF was causing the solenoid to remain energized). The fix requires a 16 gauge wire to be run from this new terminal to the "S" terminal on the aircraft starter solenoid. This connects the solenoid on the starter directly to power if the master is on the you are pushing the starter button.

The president of SkyTech (Tom Williams) is also the only engineer and so you must deal with him (unfortunately). I told him to send me a drawing (for the record). He said that he would not because it would be too much work for such a simple change. I asked him to fax me a hand written drawing or even a simple explanation. He said that he was the president and he was too busy and maybe later he would have time. I told him that my mechanic may not want to install it without some sort of paperwork from SkyTech. Tom told me that I had a "cantankerous mechanic". I got so mad that I told him that I would report his customer service techniques to the American Yankee association.

I called Chief (where I got it) to warn them about this problem. I told them about how friendly and helpful Tom Williams is and the guy laughed and said that they have never received a complaint about SkyTech products but they have received many complaints about Tom. . The guy at Chief was very friendly and thanked me for the info and took down my phone number.

The question: Do I have a problem?

It sounds like it is technically illegal to have this wire installed in my plane because the STC does not mention the wire. (Actually, the STC came with no instructions, on the other hand the installation was exactly the same as the original starter). My understanding is that SkyTech files the details of the STC with the FAA and if they make a change the STC number does not change but there is a modification to it. Is there someone that I can call to find out this or should I keep my mouth shut.

He said that he would not because it would be too much work for such a simple change.

I doubt that the FAA would share that opinion. It can also be argued that there are no "simple" changes on an aircraft.

It sounds like it is technically illegal to have this wire installed in my plane because the STC does not mention the wire. (Actually, the STC came with no instructions, on the other hand the installation was exactly the same as the original starter).

Any STC should have some sort of instructions or diagrams detailing what the modification involves, even it it only says to "remove old starter and bolt on new starter". In this case, the instructions, and therefore the STC, should be amended to read "remove old starter, bolt on new one, and run 16ga wire from terminal Q to point B." In the absence of such a revision to the STC, an official service bulletin or AD would suffice.

My understanding is that SkyTech files the details of the STC with the FAA and if they make a change the STC number does not change but there is a modification to it.

Reasonably correct. However, the FAA's approval is based on the submitted data. Changes to that data mean that the approval is (technically) not valid for the modified data. The STC is legal as it stands, without the wire. The addition of the extra wire is, from a legal standpoint, changing a wing mod by adding a few more ribs.

Is there someone that I can call to find out this

The manufacturer would be prime source for this kind of information. Failing that, you could try and call your local FAA and get an opinion from them. Or keep calling local FAA's around the country until you get the answer you want.

...or should I keep my mouth shut.

Having said all that (and probably having sent a dozen people scurrying for their maintenance records), the most practical thing would be to install the wire and not talk about it. Not that I'm recommending that you do that, because, as I pointed out, it's technically illegal and I would NEVER suggest that someone do anything illegal (wink, wink, nudge, nudge).

In this case, you have a choice of being legal (don't install the wire and risk a hung starter), safe (install the wire and prevent the starter problem), or get a different starter.

Source: http://www.i-pi.com/gg-faq/starters.html

[170C]

Here goes a IMHO item. Early on the Sky-Tec starters had a reputation of occasionally breaking the casting if the engine kicked back. I was talking to one of their employees last Saturday, who works in the repair department, and he said that at one point Sky-Tec apparently had a casting problem and have since changed to a new casting vendor and since that time he has not seen this problem except in rare instances. Of course no one wants the starter casting to break, but better that it does than a gear in the accessory case. He said the most common repair he sees is starter motors burned out from aircraft being flown by students who will crank an engine until the starter finally gives up. My IA has done some of the conversions while on the plane and he puts cardboard, heavy grease and magnets around the pinion being cut off. He says he hasn't had any difficulty with metal debri getting in the engine. I am glad to see the item George posted (button/contactor). On both my C-140 & my current plane I experienced this item failing a couple of time---once on a convention trip which caused the plane to have to be propped many times before getting back home. I could find similiar "buttons" that would fit the starter motor, but wouldn't contact as needed. The rivet holding the copper contactors failed in each case. I now think I could replace the rivet, but didn't know to do so at the time. I have no complaint with the Delco-Remy starter, but dislike the pull cable (Rube Goldberg) set up as even with lubercation it is often somewhat difficult to engage. I have also replace several starter clutches and the 5 roller one from Niagra has been much better than the older 4 roller models.

[blueldr]

My personal experience with Sky Sec precludes my ever doing business with them again,
When I installed the Continental IO-360 engine in my '52 C-170B, I elected to use a light weight starter because of the additional weight of the IO-360 over the C-145. Unfortunately, Sky Tec was my choice. The first time I ran the engine after installation, the prop came to a rather abrupt stop on shut down without any "bounce back" at all. I thought I had a siezing main bearing or some such. When I turned the prop by hand, it seemed to release and turn free. This strange condition continued on each shut down thereafter. Fortunately, I did not operae it too much during the early period of the conversion and I ran across an article about my problem on the internet. It seems that the Continental starter drive is designed so that the big spring on the drive mechanism reverses very slightly when the starter is deenergized thus releasing it from the shaft around which it wound. This reversal is accomplished by the spring reversing the deenergised DIRECT DRIVE starter motor to which it is attached.
Apprently the very small motor of the light weight starter requires a gear train to multiply the torque necessary for cranking the engine. The reversing torque of the big spring was unable to overcome the friction of the gear train to the small motor. Kind of like trying to push your car in reverse when equipped with a standard transmission. The result was that the big spring could not release it's grip on the shaft and the wear was grossly increased. This starter drive is a very, very pricey item. Just Check with Niagra Air Parts!
SKY Tec agreed, reluctantly, that they had a problem, and they exchanged it for a redesigned part for about the cost of another new starter.
No more Sky Tek products for me!

[cessna170bdriver]

I went with the significantly pricier B&C over the Sky-Tec, just because it "looked" to be better engineered, and I'm usually of a mind that I get what I pay for. Also, in reading other aircraft forums, it just seemed that more folks were having problems with Sky-Tec than B&C. It may explode the next time I use it, but as I said before, no regrets so far.

Miles