Newbee from the Great White North

[kitfoxjunky]

Hi

 

Name is Gary. Middle age guy flying a Kitfox IV 100 HP on Aerocet Anphibs. Been doing that for 15 years now, and the plane is awesome. Kitfoxjunky on YouTube if you are interested in seeing some video.

 

Having a bit of an engine issue and got some good info from a post on this site so thought I would register so I can pester the person who posted it for more info. 912S is getting almost impossible to start. Looks like the Spragg Clutch. Wanted to make sure before I yank the engine.

 

Other than that minor little hitch...life is good!

 

Cheers,

 

 

[microman]

Could be an ignition module playing up - they can cause hard starting and that then can result in the sprag clutch having to also be replaced.

 

 

[kitfoxjunky]

Here is a video clip from the other day. It was 17 deg C out when I tried it. It caught and ran fine after only a few blades Friday night. Could not get it going Saturday at all, then did manage to start it Sat night after it had sat for several hours but still was not easy. Once it starts the first time and is warm, subsequent starts are almost immediate after you engage the starter. Next day it is back to hard starting.

 

 

At 1:18 and 1:23 1:35 you can hear the starter just spinning...that happens when a kickback stops the prop.

 

So far I have replaced the battery with the Odysey 236. Lots of cranking power. New plugs. Tried gaping them to .7 mm.

 

It turns the prop quickly, but when it fires the kickback will often stop the prop. The banging around flood the crabs and when flooded there are times I can get it going if I try it at full throttle. More often than not it will try to start...sounds like firing on two plugs..but never catches. In that scenario when flooded at full throttle it is not banging and stopping the prop.

 

I have been flying behind this engine for 15 years. Was always hard to start. Been cranking it full choke with ignition off. Let it site for a minute. Then choke off and throttle cracked and starts on the first blade. Last couple of years that procedure has not been working. Used to be I only had this issue if it got below 7 deg C. Now it is happening at 20 deg C. Was doing it last year in the spring...OK to start in the summer...in the fall I pretty much gave up flying if it was not real warm out. This year seems even worse.

 

The starter itself gave me issues a couple years back. Looked like the battery was weak but it was the starter. Had it rebuilt two years ago. I guess it could be the starter is on its last legs again. When I jump the new battery with my car it really spins the prop fast, but still no luck.

 

I found this post on your forum. Guys experience sounds exactly like mine.

 

http://www.recreationalflying.com/threads/rotax-912-hard-to-start.7636/

 

 

[Kyle Communications]

I always put the fuel pump on first and let the pressure come up to around 5psi which means the bowls are full. Then I have the throttles just off the stop by a little so as if it would idle about 1800 to 2000 rpm. Then pull the choke on and spin the starter.... while spinning flick one ignition on then the other . This usually starts all the time then quite easily.

 

When I stop the engine its always at full idle and then one ign sw off then the other and the engine stops nicely

 

 

[Yenn]

Welcome Kitfoxjunky.

 

No use asking me how to start a plane in your conditions. It never gets down to 7 degrees here and that is celsius.

 

Not flying with Rotax I don't know the finer details, but kicking back against the starter doesnt sound good.

 

 

[Camel]

My suggestions,

 

Spark plugs are are culprit for hard starting ! Clean, test and gap or replace.

 

Did sound to be cranking a little slow, I would fit a power socket so you can jump start with your car, most recreational aircraft use anderson plugs.

 

I would make sure choke are operating properly and pulling full on as it is an enriching system. Your engine sounds to be firing but not running as if no fuel to continue !

 

When a Rotax gets going it's a good idea to loose the choke quickly as not to foul plugs ! Do you do this ?