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Soft Start Kit???

Y

yankee-flyer

Well Known Member
I called Van's when the firewall forward change came out about 2 months ago and was told the Soft Start kits would be shipped "in a couple of weeks". Another call two weeks later got virtually the same response. Has anybody received one yet??

Wayne 120241/143WM
 
Soft start

My engine came with yellow stickers on the ignition modules, which is supposed to be the soft start version. I remember having to add a wire or two to ignition module connectors.
Joe
 
If the ignition modules have the yellow stickers, all it takes to activate the soft start feature is the addition of a couple small wires to the harness. Mine came from Van's several weeks ago. If you haven't recieved them you should give Van's a call.
 
Soft Start

I found the website below that explains "Soft Start". Newer Rotax engines have this feature built in.
Joe
http://www.rotaxparts.net/scripts/prodView.asp?idproduct=1427
13563 Rotax Soft Start Module - 6 pin Have you had any problems with your engine kicking back during start up? The Soft Start Module (SSM) alters the timing on one ignition circuit. The SSM is designed to keep the timing retarded until after the starting sequence has finished. By holding the timing retarded longer it has been found to be highly beneficial for smoother starts on 912ULS engines fitted with a slipper clutch. The real cause of these problems is often inadequate batteries and long starter cables resulting in slow cranking speeds. The Soft Start Module helps overcome the problems caused by these short falls. Features: Fully solid state. Fully automatic, the soft start module is triggered by each attempt to start the engine. 4 pin and 6 pin options available to accommodate the two different types of connectors found on the Rotax 912 & 914 series engines. Safety Features: Single Mag ignition circuit installation, leaving the other circuit to operate as normal. (Other circuit must be wired to be switched off during starting). Twin parallel circuits for added safety backup. Available with either a 6 way plug or 4 way plug configuration to fit the type used on your engine. In order to determine which plug configuration you need to order, you will need to locate the part number on the Rotax Electronic Module fitted to your engine (See 912 parts book) or be ready to supply engine serial number when ordering.
 
Mich48041 said:
I found the website below that explains "Soft Start". Newer Rotax engines have this feature built in.
Joe
http://www.rotaxparts.net/scripts/prodView.asp?idproduct=1427
13563 Rotax Soft Start Module - 6 pin Have you had any problems with your engine kicking back during start up? The Soft Start Module (SSM) alters the timing on one ignition circuit. The SSM is designed to keep the timing retarded until after the starting sequence has finished. By holding the timing retarded longer it has been found to be highly beneficial for smoother starts on 912ULS engines fitted with a slipper clutch. The real cause of these problems is often inadequate batteries and long starter cables resulting in slow cranking speeds. The Soft Start Module helps overcome the problems caused by these short falls. Features: Fully solid state. Fully automatic, the soft start module is triggered by each attempt to start the engine. 4 pin and 6 pin options available to accommodate the two different types of connectors found on the Rotax 912 & 914 series engines. Safety Features: Single Mag ignition circuit installation, leaving the other circuit to operate as normal. (Other circuit must be wired to be switched off during starting). Twin parallel circuits for added safety backup. Available with either a 6 way plug or 4 way plug configuration to fit the type used on your engine. In order to determine which plug configuration you need to order, you will need to locate the part number on the Rotax Electronic Module fitted to your engine (See 912 parts book) or be ready to supply engine serial number when ordering.
Click to expand...

Just to clarify...
The above info is describing the aftermarket soft start module that is available to retrofit engines that were not equipped from the factory.
If I remember correctly, engines that have a yellow colored sticker on the top of the ign. module are factory equipped with the option. Those that have the green sticker are not.

As described above, if you install an aftermarket module,it is necessary to modify the starting procedure so that the engine is started with only the modified side of the ignition activated.
 
Ok. I have researched Soft Start. I read Joe's pc and looked on the R.O.A.N site where they promote the BullyHawk Soft Start Modules. I then spoke with Rotax tech at Lockwood and they sell the Rotax produced module for soft start. I wanted to find out if it's necessary to add to my 912 ULS. ( I don't seem to be having any start problems as the engine starts in about 1/2 sec. of cranking every time). Rotax feels it's a must do to preserve the life of the Sprague clutch. The reason they say is the 100 hp ULS is the high compression engine of the three in the 912-914 group and for that reason the load on the clutch is greater. The module sells for $224.00, and requires that the ignition switch be re-wired, but that work is supposed to be fairly straight-forward. Reasoning for the mod seems logical so ordered mine today.
Dick Seiders
 
dick seiders said:
The module sells for $224.00, and requires that the ignition switch be re-wired, but that work is supposed to be fairly straight-forward.
Click to expand...

As I posted previously, it does not require the RV-12 ignition switches to be rewired. You only have to rewire if using a traditional L/R/Both/Start keyed ign. switch, because you have to start with only Ignition A enabled.

For an RV-12 with two individual ign switches, you just need to change the starting procedure to leaving ign B off until after the engine has started.
 
Thanks for the feedback, Scott. I believe I misled Rotax tech when he asked if the 12 had a key start and I said yes thinking of my (former) RV6A. This led him to mention the re wiring steps. If I understand your comments correctly all I need do is turn on the master and ign switch A when cranking with the soft start module then turn on the ign B after start. Sounds a lot better than re wiring the key switch. Thanks again.
Dick Seiders
 
dick seiders said:
If I understand your comments correctly all I need do is turn on the master and ign switch A when cranking with the soft start module then turn on the ign B after start.
Click to expand...

This would be correct as long as the soft start module has been installed to control Ign. A
 
There are two different versions of the "Soft Start" avalible. One is the inline unit supplied by Bully Hawk. This product was originally designed by one of the Rotax distributors in Europe to aid in starting older engines with the low torque starters and help with hard starting engines. There technology uses a timing delay triggered off of the starter solinoid. When the engine normally starts the timing is set to 4 degrees BTDC and once the engine reaches approx. 1200rpm the ignition advances to 26 BTDC. There were issues with this because sometimes the ignition timing would advance too quickly and this let to kickback because the plugs would fire when the piston was still traveling up on its comp stoke.

Soo, Rotax decided to come out with there own version that has an actual time delay programmed into the E-boxes. This system has its advantages because it allows for an easier start procedure and you can start on both ignition systems. At the same time Rotax also changed the flywheel which controls the start timing and the run timing but not the point of transition. the new fly wheels now fire initially at -3 degrees ATDC when the piston is on its way down the power stroke. Togeather both of the features (New boxes + flywheel) make for a very pleasant start.
 
Soft Start

Two Questions Jeremy. Can the new Rotax soft start work without a new flywheel? Is the new soft start another Ducati piece of work? Thanks for your explanation of the Rotax plan and how it works.
 
Yes the Rotax soft start can be used with out using the new flywheel, the soft start handles the time delay before the ignition advances and the fly wheel handles the initial start timing weather it be 4 BTDC (old style) or -3 ATDC ( new style)

Ducati does not make the boxes, new or old, they supply the outer casing, all internal circuitry is developed by Rotax. However, the voltage regulators are a ducati product.

Sorry for the delayed response.
 
For those of you who may not know CPS (Califorinia Power Supply) is an outstanding Rotax / LSA parts, supplies. I have been buying parts from them for more years than I can to count during my ultralight days. The thing I like the best is their "On Line Store" website has the ability to order stuff 24/7 unlike some of the other Rotax parts suppliers.

http://www.800-airwolf.com/


Thanks for the info Jeremy, I ordered my soft start from you a few days ago.
 
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Jeremy@CPS said:
There are two different versions of the "Soft Start" avalible. One is the inline unit supplied by Bully Hawk. This product was originally designed by one of the Rotax distributors in Europe to aid in starting older engines with the low torque starters and help with hard starting engines. There technology uses a timing delay triggered off of the starter solinoid. When the engine normally starts the timing is set to 4 degrees BTDC and once the engine reaches approx. 1200rpm the ignition advances to 26 BTDC. There were issues with this because sometimes the ignition timing would advance too quickly and this let to kickback because the plugs would fire when the piston was still traveling up on its comp stoke.

Soo, Rotax decided to come out with there own version that has an actual time delay programmed into the E-boxes. This system has its advantages because it allows for an easier start procedure and you can start on both ignition systems. At the same time Rotax also changed the flywheel which controls the start timing and the run timing but not the point of transition. the new fly wheels now fire initially at -3 degrees ATDC when the piston is on its way down the power stroke. Togeather both of the features (New boxes + flywheel) make for a very pleasant start.
Click to expand...

So there is no confusion, there is no need to replace the flywheel when installing the soft start module. It is a "plug and play" installation that goes very quickly. The biggest issue is getting the lead to the starter solinoid.
 
What Causes Kick Back?

While we are on this subject can we get a list of things that cause Kick Back. Larry with all your experience with Rotax did you encounter this problem? So far with 85 hours on our plane we haven't seen this.

List:
Low Battery
Bad or low Octane fuel
 
Hey John - -

Bullyhawk does well at giving the key things :

1. Low Battery.
2. Undersized cables, or too long cables.
3. Poor connections of the battery cables.
( all cables involved with starting - battery, starter, ground ).

John Bender
 
Jeremy

Jeremy is the 13563 Rotax Soft Start Module that you list on your web site the same as the Bully Hawk Module? Also is yours heat sensitive? Here in Texas during the summer we operate in some serous heat.
 
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JBPILOT said:
Bullyhawk does well at giving the key things :

1. Low Battery.
2. Undersized cables, or too long cables.
3. Poor connections of the battery cables.
( all cables involved with starting - battery, starter, ground ).

John Bender
Click to expand...

4. Low Ambient Temperatures without a preheater most defineity contributes. Battery efficiency is affected. The viscosity of the oil changes.
 
What is "kick back"...

I am not sure what the symptoms would be?

Does the term mean the engine kicks backwards and therefore fails to start?

I keep a good maintainer on my battery and the engine spins up and starts readily every time, but I live in a moderate climate.
1148865108_ZYx7F-M.jpg


Tony
 
Hey Tony - -

Batteries lose power when cold. Too small, or too long cables create another problem. Cold weather makes the oil 'thicker'. If the engine turns over very slowly, and the ign fires before TDC, that can stop the engine, or nearly stop the turning over process. That rapid 'kick-back' is hard on the starting system. If your engine turns over rapidly, likely you will never have a problem.

John Bender
 
That helps...

I was thinking the same thing. I don't want to put the soft start module on unless I start having symptoms.

Thanks John
 
Silly suggestion I suppose, but could one not hit the starter, spin it up to cranking RPM, THEN turn on the ignition, or is it not connected that way?
 
Don - -

The issue is just whether the starter will turn it over fast enough to begin with. If it will, no problem. The problem is turning over too slowly.

John Bender
 
Tony_T said:
I was thinking the same thing. I don't want to put the soft start module on unless I start having symptoms.

Thanks John
Click to expand...

Tony,

You mention "symptoms"....I guess my question now becomes how many "symptoms" can your sprague clutch tolerate. My understanding is that its a somewhat fragile item, cost $1000 to replace and an engine pull. $219 might be nice insurance if it can handle the heat. CPS did not answer John's question about the heat tolerance of the Rotax module. Bully Hawk is out of the question in Texas. Guess I'll have to call them.
 
DonFromTX said:
Silly suggestion I suppose, but could one not hit the starter, spin it up to cranking RPM, THEN turn on the ignition, or is it not connected that way?
Click to expand...

May not be a silly question. The one kickback that I have experienced was when it was quite cold and at that time did not have the Reiff preheater installed. The kickback occurred within milliseconds of turning the key. The prop may have moved just a bit and then kickback.

Maybe others can comment on what they have observed and whether your suggestion might work. Would starting on a single mag minimize the potential?

I too am waiting to hear from Bullyhawk on the 180 degF temperature limit which I think may be exceeded during the hot summer months upon engine shutdown.
 
A good suggestion?

DonFromTX said:
Silly suggestion I suppose, but could one not hit the starter, spin it up to cranking RPM, THEN turn on the ignition, or is it not connected that way?
Click to expand...

This sounds like a good idea to me. The circuitry in the '12 should permit this. Does anyone know if this would be a bad idea, or have some kind of risk?
 
It may even have a healthy side effect of allowing some positive oil pressure/flow prior to making exhaust explosions bang on the rod bearings.
 
Hey guys - -

I still would not recommend it. Turning it over without the ignition on will load it up with more fuel and I feel add to a kick-back situation. Just read in the Owners manual that the ignition does not pick up until the crankshaft is at 220 RPM. Ref pg 10.3.9. I wouldn't do it.

John Bender
 
Yeah, I agree, the fuel issue would not make it a good idea, washing the oil film off the cylinder walls and making a bomb out of the muffler.
 
DonFromTX said:
Yeah, I agree, the fuel issue would not make it a good idea, washing the oil film off the cylinder walls and making a bomb out of the muffler.
Click to expand...

Either the cylinder walls or the pistons are "ceramic" coated. Wear in these areas are a non issue for the 912 series.

IMHO the best way to start a PREHEATED 912 is with the mags off, choke out, throttle full idle, run the starter for 5 seconds. This primes the system and all cylinders with air & fuel. Then mags on, choke out, throttle 1/2" in, start. Push choke in as she start running smooth. This works well for temps above 50F for me. Your milage may very.

I've never seen a "back fire" in the Rotax 912, certainly can happen, but the kick back issue is a real one. Any and all kickbacks damages the sprag clutch. It's a cumulative effect, no one kick back will kill it, several dozen will. If you are getting a kickback take immediate steps to stop it. Avoid 100LL, preheat the engine to 80F, soft start module, tune up the engine, re-balance the carbs, check the ignition pick up gap, new spark plugs, what ever it takes, but you will want to avoid kickback starts, and shut downs.

Ask me know I know. :rolleyes:
 
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I purchased a soft start module about a month ago. Still haven't installed it (too cold). I inquired of my favorite tech guy at Lockwood and he rec. it highly. I thought it would be a Rotax, but it turned out to be a Bully Hawk so I presume they have the aftermarket locked up. I mean Lockwood is THE east coast Rotax place and that's when they sent. I have looked at the installation and it is not as simple as it looks (as usual). The fuel line on my 12 lays over part of the existing start module and there is not enough room for the fuel line and the soft start when it is positioned on top of the original module. I am not planning on buying a longer fuel line so will try to find a way to attach the soft start a bit off center on the original module. The tricky part will be designing an attachment that is simple and secure. Regarding the after landing temp in the engine compartment if it tests out at greater than 180 I will pull the top cowl to dissipate the heat. I suspect tho that the problem doesn't exist or we would have heard more about it. Is the soft start necessary? Don't know for sure, but $220 is cheap insurance. Appreciate comments. Thanks.
Dick Seiders
 
Comments...

Hi Dick,
Thanks for the input on the aftermarket soft-start, it helps. I may buy one and have it on hand, but am not sure if it is needed. I still don't know what "kick-back" is or acts like. Larry can maybe comment since he says he has experienced it. Also, Marty says he had it happened at the instant he turned the key although in this case I don't understand it because the ignition is not supposed to fire until the crank comes up to 220 RPM? That makes kick-back unlikely to happen if all systems are working properly. If it happens to me, I would not want that to continue.

If I understand previous posts the aftermarket soft-start was designed for an earlier Rotax that had a lower torque starter. Since then Rotax has apparently upgraded the starter and may also have made improvements in the electronic modules (like the 220 RPM delay) that makes kick-back unlikely. And, I can understand Rotax continuing the evolution of the motor by improving it with the soft-start modules and flywheel changes.

As for the aftermarket soft-start, I am not trying to hardheaded about it, and the cost is not an issue. What I have a problem with is adding a bolt-on (which maybe has its own issues) to a high quality and well engineered piece of equipment, if it isn't needed.

added: Oh, and another factor is the already complex installation. By the time you add the soft-start module and remote locate the oil pressure sender to the firewall, the top of the engine will be a sight to behold and even harder to access parts and connections.
Tony
 
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Hey Tony, I pretty much agree with you on the installation and that is probably the second reason I have not yet installed it. I have never experienced any kickback that I could determine. The engine usually starts in about 1 second after turning the key, and zips right up to 2200 rpm.
As said earlier I took the advice of what I consider a top Rotax advisor at Lockwood. When I was having difficulty with my initial trigger coil issue he would present me with easy to follow instructions on how to diagnose the problem and it came right off the top of his head, ie; none of the usual "well I'll have to get back to you on that" ****. He is the Rotax instructor on the engine training courses so I go by what he says. I guess what it comes down to is put one on or wait until you start having the kickback, (if it ever happens) and then put one on pretty quick. So I plan on going ahead with it and should any issues arise with it I will put it on VAF. It's not clear to me if others have yet gone with this altho I suspect so. Does anyone out there who has care to talk about it?
Dick Seiders
 
Here is a good video of how to install and how the soft start module works.

http://rotax-owner.com/index.php?It...iew&id=49:ssm&option=com_content&view=article

The "kickback" is something you want to avoid at all cost. You will know it when it happens. The prop stops for 1/2 a second, (taking up the back last in the gear box) and may even come to a complete stop as the prop drags the momentum of the engine down to the point where the engine (26 degrees BTDC) fires and causes the engine to "kick back". This is EXTREMELY hard on the $1,000+ spag clutch, so stop the starter if you get into this and figure out what is wrong. Typically, you need to preheat the engine more if you have not had problems before and now it is cold.

Here is a video of what a bad sprag clutch looks like. Notice how the prop stops for just a split second, and how the operator thinks by keep ing the starter going it will somehow magically fix itself. If you get a kick back stop. Try something different.

http://www.youtube.com/watch?v=ga5AgzkPNgM


3 days and $1,000+ to repair yourself, or $2,000+ if you hire someone. You have to pull the engine, and have a very specialized gear puller that costs $200. There is a reason the soft start module is standard equipment now. IMHO better get one and put it on.

Other causes of the sprag clutch going bad is constant 100LL use. Rotax says to just decrease the oil change intervals to 25 hours, but IMHO 100LL should be avoided for daily use. If you are going cross country fine, but use mogas when ever possible. Even occasional use of 89 octane mixed with 100LL is better than straight 100LL.

Hopefully, I don't sound like a know it all, certainly I am not. Just trying to get info out to RV-12 owners. I have owned several Rotax 912 (80 & 100HP) and have delt with these issues for more than a decade, and I learned the hard way on replacing the sprag clutch. It is MUCH easier to avoid the problem now than to fix it later.
 
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A couple of tricks I have learned with the -12 is the Dynon is an excellent source for preheat info. Make sure the engine / oil /chts are all 50-90F before starting it. AND! the 12volt outlet is hot all the time. This is a perfect place to plug in a battery maintainer. Kick backs are less likey then.

JMHO.


Let me know if you need clarification on anything. I'll be glad to try and help explain what little I know, and I am always open to learning new tricks.
 
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Now you're talking...

Larry, I now get the whole picture. Thanks. I have ordered the soft-start module.
Part #13563 for the 6 pin connectors (visible in the picture) is the right unit for my 912, but every one should check their connectors before ordering one.
762671902_RtBMj-L.jpg


And I agree that the 12 volt power plug is a good place to plug in the battery maintainer. I run the cable thru the cockpit right hand air vent and that way don't have to close the canopy on the wires.

Tony
 
Installed my Bully Hawk Soft Start yesterday and did a final check and test run/flight today. When I cranked the engine to start it on A ign (that is where the soft start is connected ) it kicked back one time in the process of starting! Go figure. Never happened before in 50 hrs of flying. I assumed it was just an anomaly ( my battery is fine) and turned on the B ign w/i a couple seconds after start. The engine ran a little rough for about two minutes and I was beginning to consider shutting it down, but persevered and it smoothed out after it got up to 120 degrees oil temp. I did the run up and it was good (120 rpm drop on both ignitions. Flew for about 40 min. and all was fine. I did note the oil temp climbed to 210 by the time I leveled off at 5500', but it began to drop as soon as I had nose level. I will check the temp. test strip on the SS module tomorrow. My first test on that was before installing the SS, and it never reached the min. 150 degree level. I will run another test start and flight and provide any meaningful data feedback.
Who else out there has installed the SS and were there any interesting events coupled with the test?
Thanks for feedback
Dick Seiders
 
Good feedback

Dick, thanks for the update. Keep us informed. I have the same soft-start module but have not installed it yet.
At 50 hours also, I have not had any any kind of starting problems, and I am very reluctant to install a third party ignition part on this motor, despite all the dire talk about kickback.

Tony
 
Tony, et al,
Day 2 of soft start. Checked the temp. tabs this am after flying yesterday, and temp. in the area of ign. modules did not reach the min. level of 150 degrees F. The allowable temp. limit is 186 degrees so we are good to go there. At startup I experienced no kickback, but I had to start 3 times to get it to keep running. I think it was a choke issue as it warmed up to 57 taday at startup time. After start on ign. A I turned on B and engine ran very smoothly. I warmed it up to 120 and did a normal runup to 4000 rpm and drops were w/i limits. Took off and flew for 1.1 hrs and engine was very smooth, and vibration free. I am feeling good about the soft start now.
To ease the installation I added velchro under the SS module to attach it to the original. Had to offset it only slightly aft to clear the fuel return line, but that's not a problem as the SS module is a bit shorter in length than the original. I then added two wire ties to finish the attachment. The only other thing to do was to re-rout the coolent return line a bit to keep it away from the SS module. I didn't take a photo of the installation (duh) but I will tomorrow and send it to you.
Dick Seiders
 
I agree Didck. I just added the soft start to my -12. I was not having trouble, but I just wanted to avoid trouble after having to replace the sprag clutch in another plane years ago. The install is straight forward, and it works as advertized. Very happy with the results.

If you are having starting issues double check the carb sync. If that does not cure it I highly recommend the soft start, and so does Rotax.
 
I had a chance to really test the Soft Start module today and I thought I would report my findings. I installed it a couple months back, but I have just started the engine after preheat with no issues. I would leave the right "mag" off and just start it on the left mag with the engine heated to around 60 - 90F. It would start okay, but I always wanted to know how the Soft Start would act with a cold start. Today, with no preheat I had to move the plane to my work hanger. With temps in the 20's last night and temps when I started it in the 35F range this would be a good test. Cold starts can really cause a serious kick back in the Rotax 912S.

Well, I pulled the choke (enrichment circuit :rolleyes:) out, set the throttle to idle, left mag on, right mag off, fuel pump on (mine is switched ;)) it started smooth as silk! I let run for 3-5 seconds before turning the right mag on, then I let it run for 10 seconds or so full choke. I then slowly pushed the choke in. Increased throttle to a smooth idle of 2500 rpm or so and it could not have been a smoother start. :D Oh Yea Baby! :D

Unless you want to pull the engine and replace the $1,500 sprag clutch (been there, done that) Rotax & I HIGHLY recommend you invest in the Soft Start module. I could not be more please with the function of this after market ignition module.
 
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Temps

I will say I was concerned about the 180 degree limit because I live in Texas. Then I weighed $200 vs the cost of a sprague clutch and talked to Lockwood some because they are in a hot weather environment as well. They said they have em all all their training aircraft and wouldn't be without one. Of course Rotax now has it built into their ignition modules. So yes I have one now as well and will support all claims made by Larry (as usual..lol).

Pete
 
Information please

Pete - you say that Rotex now has the soft start on their engines. That is good as I see it. But you had to purchase yours. Does that mean that the engine that I purchase from Van's will have the soft start already installed? Did I miss that info somewhere? Please advise and thanks very much.
 
Soft start now included

Does that mean that the engine that I purchase from Van's will have the soft start already installed?
Click to expand...
That is correct. My engine ignition has the yellow stickers indicating latest version with soft start.
Joe
 
The "soft start" started out as an after market add on, but it was so successful in preventing kickbacks and damage that Rotax incorporated it into a revision for latter serial numbers. If I can not convince you to buy one, that should. ;)
 
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