Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
MZ 202 starter motor
#1
Smile 
I have an MZ202 engine in my MiniMax homebuilt fixed wing, so I hope I'm allowed on this forum Smile  But you guys know way more about the MZ than any other group I can find.

I have just under 30 hours on the 202, and it has performed faultlessly so far - it's a great engine.

But I strapped in to go flying yesterday, and when I hit the starter button, the starter motor spun up to speed, but wouldn't engage the engine ring gear. Voltage is good - 12.6v - and the starter motor is definitely spinning up, but won't turn the engine.

I tried tapping the motor casing when it was running to maybe free up the Bendix gear, but no good.  Has anyone had this problem? I'm guessing it is a sticky Bendix, but I haven't taken the starter motor off yet so don't know the internals. Should the engagement mechanism be lubricated? Some say not.

Any help gratefully received. I can't go flying until it's fixed, because it's hard to hand prop the engine with the clutch disengaged (or rather too easy to swing the prop!).

Thanks

Bruce
Reply
#2
Hi, I had a similar thing happen with my starter motor. It wasn't good news when I found what had happened. The shaft had sheared so the motor was spinning, but no output. The best thing you can do is take it out and see if it is the same result as mine. It happened to me when I was having starting issues and it just gave up!
Reply
#3
(06-17-2017, 12:29 AM)beragoobruce Wrote: I have an MZ202 engine in my MiniMax homebuilt fixed wing, so I hope I'm allowed on this forum Smile  But you guys know way more about the MZ than any other group I can find.

I have just under 30 hours on the 202, and it has performed faultlessly so far - it's a great engine.

But I strapped in to go flying yesterday, and when I hit the starter button, the starter motor spun up to speed, but wouldn't engage the engine ring gear. Voltage is good - 12.6v - and the starter motor is definitely spinning up, but won't turn the engine.

I tried tapping the motor casing when it was running to maybe free up the Bendix gear, but no good.  Has anyone had this problem? I'm guessing it is a sticky Bendix, but I haven't taken the starter motor off yet so don't know the internals. Should the engagement mechanism be lubricated? Some say not.

Any help gratefully received. I can't go flying until it's fixed, because it's hard to hand prop the engine with the clutch disengaged (or rather too easy to swing the prop!).

Thanks

Bruce
Hello,

Voici le problème que j'ai rencontré avec le démarreur de mon MZ202.
http://forum.mosquito-helicopter.info/ez...w&id=13058
http://forum.mosquito-helicopter.info/ez...w&id=13059

Hello,

Here is the problem I encountered with the starter of my MZ202.
http://forum.mosquito-helicopter.info/ez...w&id=13058
http://forum.mosquito-helicopter.info/ez...w&id=13059
Jean-Rémy (XE 1077 - Sud Bretagne - France)
Reply
#4
The small sprocket of the starter motor may be blocked. If it is enough to disassemble it and try to unlock it. I had this poblema 2 times.
However it is a powerful engine but generates many vibrations that tend to disassemble all engine components.
I personally had problems with the starter, the cooling fan, and finally the engine crankcase cushion.
Powerful engine but too much vibration.
Maurizio
Reply
#5
Thanks for the responses, guys.

I took the starter motor off the engine today. Sure enough, the small gear was stuck at the end of the Bendix shaft. I freed it easily enough on the bench.

I will thoroughly clean & dry the helix threads, then apply some silicon spray. This is said to dry completely, & so hopefully not hold any grunge that would jam it.

Thanks for your help.

Bruce
Reply
#6
Silicone Spray does leave a sticky film so next time use dry graphite spray.
I dries completely and is not sticky after, so it wont cling to any dust/dirt particles.
Ray
Reply


Forum Jump:


Users browsing this thread: 1 Guest(s)