Home > VansAirForceForums

- Donate yearly (please).
- Advertise in here!

- Today's Posts | Insert Pics

Old 04-18-2017, 12:01 PM
Bigsteve Bigsteve is offline
Join Date: Apr 2013
Location: janesville, wi
Posts: 16
Default loose 912 uls carburetor

After landing on rollout the engine started running very rough. It turned out that the left carburetor screw had backed out of the intake manifold exposing the intake to atmosphere on the left side cylinders. It appears no combustion was occuring since the egt probe showed only 170 degrees. checked the threads, not stripped, re-torqued to 18 foot-lbs & 1 drop of lock-tite. Restarted & seemed to run fine. Best guess is that the engine ran for 5 min on the right side only. Do you think that there is any severe engine damage ? Plan on flying in the pattern later today or tomorrow. Thanks for your expert advice
Reply With Quote
Old 04-18-2017, 01:06 PM
John-G John-G is offline
Join Date: Jan 2012
Location: Northeast Ohio
Posts: 493
Default Bore scope


My suggestion would be prior to making any further flights find a friend who owns a bore scope or purchase one of the ones that the VAF members have said good things about and carefully look at the pistons and valves on the side of the engine the screw was found to be lose.

I would be concerned that as the screw was becoming lose (especially if it occurred over a long period of time) that it would allow that side of the engine to get very lean .... which over a long enough period of time could possibly lead to damage. Doubt you will find anything nasty, since you have made no mention of high EGT temps, but after a quick look you will have piece of mind.
RV-12 Wings, Empennage, Fuselage, Finishing, Avionics and Powerplant kits all completed
Now Flying!!

Dues paid until September 2018
Reply With Quote
Old 04-19-2017, 07:31 AM
Boyd Birchler Boyd Birchler is offline
Join Date: Sep 2014
Location: IN
Posts: 139

Doubt it did any harm.
Similar to having one carb cable break.
Reply With Quote
Old 04-19-2017, 02:49 PM
Maverick 4003 Maverick 4003 is offline
Join Date: Dec 2013
Location: N.E. Wyoming
Posts: 73
Default 912ULS

Having had only 914Turbo + current 912S in EAB, IMO, too short duration for lt. resultant damage. However, as admirably stated to avoid apprehension, either call LEAF, ask for Brian + or other in back shop line, younger Rotax gurus - or Ronne (Smith) LSA of So Miss., (Lucedale), gray haired Rotax guru flies one himself + hosts fly-in. Ask for him, over Son Morris, again, on the shop back line. They may ask you for engine S/N, Ronnie will. BTW, isolated incident, no known SB to address this I've known of.
Reply With Quote
Old 04-19-2017, 11:26 PM
RFSchaller RFSchaller is offline
Join Date: Oct 2010
Location: Phoenix, AZ
Posts: 2,224

I had a 912 stop when I was with a student doing stalls. Fortunately it started back up when we cranked it and didn't have to make an emergency landing. The cause was a carburetor that did not seat properly in the socket and worked its way loose. Reseated it and no further issues.
Reply With Quote

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

All times are GMT -6. The time now is 03:40 PM.

The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.