Kick back

[wannafly]

Had a prop strike so sent engine in just to be sure everything was ok. They replaced one disc in clutch and I asked them to put in the soft start module while they had it. They also put in a new fly wheel that was supposed to improve starting. It kicks back more now then it ever did before. Plus it starts very hard. I thought this was going to make it easier on the engine. Any ideas out there? Should I just put it back the way it was?

[mbuckner]

Good morning,

I am new to LSA ... what is a soft start module?

Best regards,

Mike

[kmach]

My new 2015 912uls engine with the factory soft start, spins fast and fires instantly. It has the HD starter.

You need a good battery to get the rpm for the modules to fire, my first thought is your battery may not be up to the task or a little weak.

I have heard of kickback problems from a weak battery.

I think if I remember right if kickback is a common regular, occurrence the sprag clutch gets damaged.

I would try a new battery as the first simple solution,
I would also recheck the wiring setup for the soft start, If I remember right there are two wires from each module plug that join together and hook onto the starter solenoid .

Did you get this work done in Vernon?

Good luck Mic

[Paul Z]

Carb problems can also cause hard start problems.

[Slyfox]

I have the 912uls. Yes they can have problems. I notice more kickback if under 50degrees. I try to plug my motor in so it thinks it's summer time. Ha ha. anyway, I always have a battery tender on my battery I have the big odyssey. I have the slipper clutch and the hd starter. to aid in my start I normally have my idle set at 500rpm so I can pull the throttle all the way back to start. I first pull the choke and let it crank for about 6 seconds. that's with the mags off. Then I only turn one mag on, then I crank the engine with throttle all the way off, as it fires I add throttle to 1800 or higher as needed to make it run nice. then I turn the other mag on. This morning it was right at 50 and it started real nice. having the idle real low really helps in starting. when I shut down I pull the throttle all the way off and turn off the mags at the same time. stops right now, no kick.

One more advantage is when landing I can pull all the way back with flat prop(ivo adjust) and I have nice engine braking. I just have to add throttle as I touch down so I maintain 1800rpm.

If you can't handle a friction lock throttle then install a vernier throttle. That's works really nice with this setup.

[kmach]

If carbs are setup right, and you have a good battery there should be no voodoo starting method.

Throttle idle, mags on , activate starting carbs, push starter. Advance throttle to keep rpm at 2000 area while deactivating the starting carbs.

With the soft start modules it will run slightly rough for a few seconds then it will smooth out.

Below 10 degrees celcius I preheat if available.

I am using the EarthX 36C battery ,HD starter, it cranks and spins the uls fast and easy . It fires up shockingly fast.

[Slyfox]

I assume you are calling my start a voodoo start. On a model 4 you better not have any shake on startup or you will drop a carb. the carb socket will break or the carb will come completely off. nuff said. my way, works great for a model 4

[jiott]

Just curious, why would the starting method differ on a Model 4 vs. Model 7 as long as we are talking about the same 912uls engine?

[DesertFox4]

Jim, the 4 motor mount requires you to switch intake manifolds from one side to the other to clear the mount tubes. Puts the carbs farther to the outside of the engine and more prone to spilling fuel on hard starts. I pretty much use Steve's start method too. Not really needed on the model 7's I fly.
I do not have soft start or the Heavy duty starter on my 912ULS.

[Slyfox]

I started that procedure way back on my 912ul. another thing you need is the small round filters. keeps the weight off the carb. The great side effect is being able to idle way down on short finals and make the runway :)

[Dusty]

I don't know the details,but one of our flying group had similar issues.The local smoke wrangler(electrician) installed two small toggle switches that were turned on(or off?)once the engine started.smooth starts from then on.

[wannafly]

Good news new battery installed. Bad news no change. Carbs were synced about 3 hrs ago. I will try adjusting my start procedures to meet the methods some of you have suggested. Will check carbs over again and check the wiring on the soft start modules. Stay tuned and keep ideas coming.

[phintz]

Just curious, why would the starting method differ on a Model 4 vs. Model 7 as long as we are talking about the same 912uls engine?

I was wondering the same thing. I did install the soft start mod. It does help alot! guessing it reduces the startup shake by 30% or so. I pull out the throttle completely out, pull the choke, leave 1 mag on, 1 mag off, start engine and then advance throttle once it fires then turning on mag. The tricky part is adding throttle just at the right time.

Patrick, kitfox 6 , 912 uls 100 hp

[wannafly]

Arrived at Rotech. Did some testing and determined a sprag clutch and HD starter were required. So repairs are done and engine is back on. Test first thing in morning...will keep you posted.:eek:

[DesertFox4]

Hope that solves your issues Mic.

[wannafly]

Goods news. It fired right up. Purrs like always. Things I learnt. Rotech is top notch. They let me work along side as it was being done. The special tools that were needed prevents others from being able to do it. The tolerance of the fit is mind boggling. Amazing it would even start with how the old sprag clutch looked. Regular starter spun at 210 rpm, new HD starter spins at 340 rpm...big increase. The soft start flywheel and module really are amazing. Seen it on the test stand with a strobe light really shows how it works. Yes the parts are expensive :( but Rotech gave me a discount:D
Just happy to be up and flying again once this spring storm blows over. Any other questions I'd be happy to answer

[kmach]

Glad to hear you got it fixed up

[DesertFox4]

Very good news. Sorry your checkbook took a hit but sounds worth the expense.

[kitfox2009]

Hi Mic
Glad to hear things are working out. One thing about this "flying habit" that is common to the oilfield and possibly farming is that you just have to keep throwing money at it until it works. You engine, Me avionics.
Maybe if we have a good streak of weather this summer I will get out your way again. Safe trip home.
Cheers
Don