Soft Start Conversion - flywheel or no flywheel

[JJay]

I've finally run out of luck with my ignition modules on my 2006 vintage 912ULS. Wouldn't start unless I put ice on the modules, so I guess they need to be replaced.

But I'm confused about whether or not I need a new flywheel hub (part number 866972) to make the soft start feature of the new modules work. The way I read SI-912-028, my engine falls into category C (serial number 5646486). Category C indicates that the flywheel hub AND the easy start unlock cable AND the new modules all need to be purchased. But then, I've read in other places that as long as I have the 6/6 pin connectors (I do), I only need to replace the modules and add the unlock cable.

Anyone else been through this and have a definitive answer?

[3Dreaming]

I would just do the modules. They will make a difference. The thing is you will not get the full effect without the flywheel, but you will get all you need.

[ShawnM]

You do not need the flywheel to enable the soft start with the new modules. I did the very thing you are looking to do Jeff. I replaced my bad modules back in 2016 with the soft start units and it made a world of difference. It's a much smoother start with just the modules alone. I was able to find the 2 for 1 pricing in the UK when that deal from Rotax was all but over. I didn't add the flywheel but I did add the "unlock" cable as they call it. It's just a wire that runs to your starter solenoid that is split to both modules into the empty socket. The kit I bought came with the connectors and rubber seals, all I had to do was crimp on some wire and run it to the solenoid. Instant soft start.

A bit of history for you Jeff, as you know your previous owner and I used to share a hangar at X35. When my ignition modules started acting up in December of 2015 and I wasn't sure what the issue was Eugene let me take the ignition modules of his plane (your plane now) and put them on mine to test out theory. Sure enough my plane started right up with Eugene's modules. So that's when I ordered the kit from the UK.

There was a time when Rotax was offering a BOGO on an "ignition module kit", yup, a true "buy one get one". This was for a short time in late 2015 because in January of 2016 I couldn't find this "kit" anywhere in the US. So I scoured the web and found one kit still on the shelf in the UK at a Rotax dealer there. I paypaled them the money and less than a week later they were at my doorstep. This saved me nearly $1000.

[3Dreaming]

Last night I was pecking on my phone for the reply. Adding the modules will not make it like the soft start on a new engine. With the new modules you have 3 choices. First just install the modules, and the engine will start and run just like before. Second as Shawn stated add the wire from the starter solenoid and activate the electronic portion on the soft start system. This is what most people do. Third ad the flywheel and make it like a new engine. Not worth the effort in my opinion.

There is one more option that is less expensive, with a fairly quick turnaround. If you are experimental you can send your old modules to Carmo in the Netherlands https://www.carmo.nl/ It will cost about $500 to repair both modules, and they supposedly activate a soft start feature that doesn't require adding a wire. I have not heard anything but good things about them. I did remove a pair of modules for a customer to send out for testing , then reinstalled after testing , and the airplane ran great. Must have been something about the testing they did.

[JJay]

Thanks folks for the great info. [I LOVE this forum!]

In my research I learned about the once-upon-a-time BOGO kits. Those seem to all be long gone. Sure wish Eugene had ordered one back then .

I have read some bad things about the Camo repair. Several forums have tales of the Camo-modified units failing after a few months. Obviously, "mileage varies" for everyone but it's really not an option for me anyway since I'm not Experimental (yet?).

I guess I have one more option. I could replace just one of the modules, forget the soft start unlock cable, and save $1K. It has probably been starting with only one module for some time now (they didn't likely both die at the same time). It's not the "right" thing to do, but it is an option - isn't it?

[ShawnM]

Thanks folks for the great info. [I LOVE this forum!]

In my research I learned about the once-upon-a-time BOGO kits. Those seem to all be long gone. Sure wish Eugene had ordered one back then .

I have read some bad things about the Camo repair. Several forums have tales of the Camo-modified units failing after a few months. Obviously, "mileage varies" for everyone but it's really not an option for me anyway since I'm not Experimental (yet?).

I guess I have one more option. I could replace just one of the modules, forget the soft start unlock cable, and save $1K. It has probably been starting with only one module for some time now (they didn't likely both die at the same time). It's not the "right" thing to do, but it is an option - isn't it?

This is a great forum with lots of great info.

I've also heard of the company in the Netherlands but dont know anyone who has had their modules repaired.

Here's a thought Jeff if you are interested......I still have both my old modules at my hangar and I don't know which one is bad, I never had them tested because I have new soft start ones. You are right that it would be unlikely that both go bad at the same time but stranger things have happened. I'd be glad to send you both my modules and you can see if one might still work. You are welcomed to it if one still works. Let me know.

[MrMorden]

The flywheel is just a big hassle and expense, IMO. Just get the modules. I swapped mine out in a few minutes, the only part not plug and play is running an additional wire for the soft start function that takes a couple of minutes. If the flywheel bought another 500hrs to TBO it might be worth it, but as is it's just a "nice to have" item and requires removing the engine since it's on the back side. You'll definitely notice a difference on starts with just the modules.

[MrMorden]

I've also heard of the company in the Netherlands but dont know anyone who has had their modules repaired.

Here's a thought Jeff if you are interested......I still have both my old modules at my hangar and I don't know which one is bad, I never had them tested because I have new soft start ones. You are right that it would be unlikely that both go bad at the same time but stranger things have happened. I'd be glad to send you both my modules and you can see if one might still work. You are welcomed to it if one still works. Let me know.

One of the guys on the CT Forum did the Neatherlands repair. He was very happy with it, but he sold the airplane shortly after the repair so I don't know if we'll ever get the long term report on that. Having paid the $2000 for new modules, I would definitely consider the repaired modules if I had to do it again. You might end up paying $500 more in total if you still have to replace them later, but if not you save $1500. I like the odds.

BTW, for people who have not replaced their modules: If you send both modules to Lockwood, they will test them for (IIRC) $75. If you need replacement of one or both module(s), they will roll the test cost into the module price if you buy from them. They also send you a wiring sheet on how to install them and they pre-install the extra soft start wire into the connector for no additional cost; I think the modules themselves from Rotax don't have any docs with them and you have to punch down the wire yourself. It's a pretty good deal, it's what I did.

[Wm.Ince]

. . . . . One of the guys on the CT Forum did the Netherlands repair. He was very happy with it, but he sold the airplane shortly after the repair so I don't know if we'll ever get the long term report on that. Having paid the $2000 for new modules, I would definitely consider the repaired modules if I had to do it again. You might end up paying $500 more in total if you still have to replace them later, but if not you save $1500. I like the odds.

BTW, for people who have not replaced their modules: If you send both modules to Lockwood, they will test them for (IIRC) $75. If you need replacement of one or both module(s), they will roll the test cost into the module price if you buy from them. They also send you a wiring sheet on how to install them and they pre-install the extra soft start wire into the connector for no additional cost; I think the modules themselves from Rotax don't have any docs with them and you have to punch down the wire yourself. It's a pretty good deal, it's what I did.

Thanks, Andy. I will keep that in mind.
Good information.

[JJay]

Here's a thought Jeff if you are interested......I still have both my old modules at my hangar and I don't know which one is bad, I never had them tested because I have new soft start ones. You are right that it would be unlikely that both go bad at the same time but stranger things have happened. I'd be glad to send you both my modules and you can see if one might still work. You are welcomed to it if one still works. Let me know.

Awesome Shawn! I believe I will take you up on it as an interim until I get the new module details worked out. PM me and let me know your availability this weekend or next. I'll either fly over or drive over (and get some gas from McMullen) if we can work out a time. If all goes to plan, we'll eventually figure out which one of the four is still good and have an emergency spare to share.

[TakeTwo]

My 2 cents, for what it is worth. Something over a year ago, after about a year of ownership, I was sure that I was heading for module replacement in my P2004 Bravo (2006) - it became difficult to start and icebags consistently made for quick-and-easy starts. Obvious signs:replace the modules @ $$$$.

However... I came across a blurb that led me to believe that I had developed the habit of cracking the throttle too bit (maybe 1/16"), I tried a new approach of BAAAAARELY cracking the throttle (maybe 1/64" . The results were immediate and startling. Now the engine starts usually by the 2nd prop.

[FastEddieB]

I believe the BING’s starting circuit is designed to work best with the throttle completely closed, though many checklists do mention a partial opening.

Good explanation of their operation here: http://www.omnilex.com/public/bmw78/cvcarb.pdf

Written for the BING’s on “airhead” BMW motorcycles, from which ours were lightly modified.

[ShawnM]

Awesome Shawn! I believe I will take you up on it as an interim until I get the new module details worked out. PM me and let me know your availability this weekend or next. I'll either fly over or drive over (and get some gas from McMullen) if we can work out a time. If all goes to plan, we'll eventually figure out which one of the four is still good and have an emergency spare to share.

PM sent, give me a call when you can and we'll meet up.

[JJay]

BTW, for people who have not replaced their modules: If you send both modules to Lockwood, they will test them for (IIRC) $75. If you need replacement of one or both module(s), they will roll the test cost into the module price if you buy from them. They also send you a wiring sheet on how to install them and they pre-install the extra soft start wire into the connector for no additional cost; I think the modules themselves from Rotax don't have any docs with them and you have to punch down the wire yourself. It's a pretty good deal, it's what I did.

Traded emails with Dean at Lockwood. His opinion: if the engine didn't start, then did start after 20 minutes of ice on the modules, there is no reason to send in for a bench test - that is a test, and they failed. He didn't know of a deal for no cost pre-install of soft-start wire, but it's easy enough to do with their "Y Wire" kit. Also, there is a video demonstrating installing the soft-start wire on rotax-owner.com (https://rotax-owner.com/videos-topmenu/ ... 1-asm-esuc). Part numbers are 965 444 for the modules ($904.39 a piece) and ELSSW-1 for the soft start wire and fittings ($29.95).

[FastEddieB]

One test to see if spark is being generated is to hook up an inductive timing light. When mine were questionable, I bought one for about $30 and it confirmed no voltage in the spark plug wires. I was lucky my 2007-vintage modules failed during ROTAX's 2-for-1 special.

As an aside, normally one can check for spark by removing a spark plug and cranking with the plug grounded and looking for a spark (I did it yesterday troubleshooting a riding mower). I've been told that doing that with a ROTAX is a bad idea - if the ground is not firm its detrimental to the coils to try to fire to an open circuit. Maybe someone else can confirm this precaution.