912 UL cold start trouble shooting
in 912 / 914 Technical Questions
8 years ago
Hello.
After owning a 582 for many years, I recently bought a 2005 WSC trike with a low hours 912 UL (145 hours TT). Everything is in good order and well maintained, except for one thing... It does not start well when it sat for a couple of days or more. Only after repeated tries with full choke (at least 4 long times or more) or with the use of starter fluid will it fire up. The good news is that after it ran (even if it was just for 10 seconds), it will restart immediately without any problem whatsoever.
I have been told that "some of these older engines are just like that, and I shouldn't worry about it too much". "Just be patient or use starter fluid".
Clearly I'm not satisfied and want to get to the bottom of this. The two Rotax mechanics I spoke to agree and have been helping me trouble shoot. Nevertheless, I wanted to share this 'quest' on this forum and see if anyone has had a similar experience or good advise for me. Or if nothing else, I thought it would be good to document for future reference.
What we checked and planned to do so far:
- Fuel supply to carburetor seems ok. Bowls are filled. Pump is working well.
- Choke is fully opened when cranking.
- Replaced battery with a brand new lithium version.
- Starter motor appears to be ok (sounds good) but haven't been able to test fully.
- Spark plugs appear to be ok with correct gap (although I only checked one so far; will be checking others)
- Carburetors have been balanced.
- Idle is set to 1800 - 1900 (which I've been told is a little high, so will lower that to 1750).
- It was also suggested to check idle mixture adjuster knob, which we'll do as well (turning 1.5 times outward).
So there you have it. I look forward to sharing future results and hearing from others.
Maarten.
After owning a 582 for many years, I recently bought a 2005 WSC trike with a low hours 912 UL (145 hours TT). Everything is in good order and well maintained, except for one thing... It does not start well when it sat for a couple of days or more. Only after repeated tries with full choke (at least 4 long times or more) or with the use of starter fluid will it fire up. The good news is that after it ran (even if it was just for 10 seconds), it will restart immediately without any problem whatsoever.
I have been told that "some of these older engines are just like that, and I shouldn't worry about it too much". "Just be patient or use starter fluid".
Clearly I'm not satisfied and want to get to the bottom of this. The two Rotax mechanics I spoke to agree and have been helping me trouble shoot. Nevertheless, I wanted to share this 'quest' on this forum and see if anyone has had a similar experience or good advise for me. Or if nothing else, I thought it would be good to document for future reference.
What we checked and planned to do so far:
- Fuel supply to carburetor seems ok. Bowls are filled. Pump is working well.
- Choke is fully opened when cranking.
- Replaced battery with a brand new lithium version.
- Starter motor appears to be ok (sounds good) but haven't been able to test fully.
- Spark plugs appear to be ok with correct gap (although I only checked one so far; will be checking others)
- Carburetors have been balanced.
- Idle is set to 1800 - 1900 (which I've been told is a little high, so will lower that to 1750).
- It was also suggested to check idle mixture adjuster knob, which we'll do as well (turning 1.5 times outward).
So there you have it. I look forward to sharing future results and hearing from others.
Maarten.
