Pickup from idle

by stephen eyers in 912 / 914 Technical Questions 9 years ago

912ul when increasing power rapidly from idle the engine hesitates and almost seems to misfire for a few moments finally picking up and running normaly. Carbs striped blown through with new O rings. Floats good. Balanced and drop ok. Also found plugs 2 & 4 black. Moving needle to position 2 seems to have improved black plugs but not thevrunning problem. The engine has 200hrs as original.

Re: Pickup from idle

by Roger Lee » 9 years ago

Roger Lee

126 5.13k 4.55k

You may just be advancing the throttle too fast and it wasn't really meant to slam it forward. Not sure how fast rapid is. A nice steady even advance of the throttle will give better overall performance.

If you had been running at idle then the black dry sooty plugs may have been normal and changing the needle clip was unwarranted and depending on your elevation at your home area may be running a little lean. To check plugs the engine needs some high rpm run time (about 2-3 minutes) and then to idle and immediate shut down. No idle time. The hesitation can come from friction in the throttler cable housing affecting the cable smooth operation, dirty carb slide/piston, poor carb sync by setting it up at too low an rpm, too fast a throttle increase from a too low an idle rpm (i.e. 1500) (this one is more common).

Roger Lee
LSRM-A & Rotax Instructor & Rotax IRC
Tucson, AZ Ryan Airfield (KRYN)
520-349-7056 Cell

Report

You do not have permissions to reply to this topic.

Title	Category	Replies
Idles too fast	912iS Technical Questions	2
Right side EGT normal then drops at idle	912 / 914 Technical Questions	7
P2006T，912S ，MAP value be at idle	912 / 914 Technical Questions	2
Idle RPM Variation	915iS Technical Questions	1
What’s your 912iS idle rpm set to?	912iS Technical Questions	18

Pickup from idle

Recent Videos

Safety First!

ROTALK News

Prize Giveaway!

Log In/Out

Login