Kitfox Aircraft Stick and Rudder Stein Air Grove Aircraft TCW Technologies Dynon Avionics AeroLED MGL Avionics Leading Edge Airfoils Desser EarthX Batteries Garmin G3X Touch
Page 2 of 2 FirstFirst 12
Results 11 to 20 of 20

Thread: 912 uls carb vent lines

  1. #11

    Join Date
    Jan 2019
    Location
    Windsor, California
    Posts
    8

    Default Re: 912 uls carb vent lines

    It should be noted that the carb drip pans serve two functions: 1) to deflect venting carb fuel from falling directly on the exhaust pipes and 2) to somewhat insulate the carb bowls from heat radiated by the exhaust pipes.

  2. #12
    Senior Member HighWing's Avatar
    Join Date
    May 2009
    Location
    Goodyear, AZ
    Posts
    1,743

    Default Re: 912 uls carb vent lines

    Likely true, but in my 2 Model IVs, I had the drip pans on the first one and the pictured (previous post) variation on the second because I found with the nine years I had the drip pans, they made routine inspections and adjustment of the carburetor much more difficult as the float bowl couldn't be removed without separating the carburetor from the manifold as the drip pans I used were bolted to the manifold (Picture below). In the normal running of the engine - ground and flight - there was no apparent difference with and without. This latter was emphasized when I started flying with the local group of six as we began exploring California and the back country of Idaho. We flew together for 7 or 8 years and none of the other guys had drip pans.
    Attached Images Attached Images
    Last edited by HighWing; 03-18-2020 at 10:50 AM.
    Lowell Fitt
    Goodyear, AZ


    My You Tube Channel

  3. #13
    Senior Member
    Join Date
    Mar 2009
    Location
    Summerland BC Canada
    Posts
    411

    Default Re: 912 uls carb vent lines

    I know this method will not meet the requirements of many of our "professional" builder/owners but for almost 900 hours now I have zip tied a piece of heat shield material purchased from a local auto supply store under the carbs. The auto performance folks use this to insulate starters etc from extreme engine heat. I attach it to the manifold and carb throat so it forms a "bag" under the carb. Keeps heat away and prevents fuel from running on the exhaust. Easily removed for servicing. I also run the vent tubes into the air filters.

    I can post pics if anyone is interested!

    Take care and be safe. I find the best way to self isolate is IN the HANGER or better yet IN the AIR!


    Cheers
    Don
    Vixen C-FOXK 912UL IVO IFA

  4. #14
    Senior Member Delta Whisky's Avatar
    Join Date
    Dec 2017
    Location
    Amissville, VA
    Posts
    637

    Default Re: 912 uls carb vent lines

    Don - I'm interested in the pictures - when you get time. Thanks, Darrel

  5. #15
    Senior Member
    Join Date
    Mar 2009
    Location
    Summerland BC Canada
    Posts
    411

    Default Re: 912 uls carb vent lines

    Quote Originally Posted by kitfox2009 View Post
    I know this method will not meet the requirements of many of our "professional" builder/owners but for almost 900 hours now I have zip tied a piece of heat shield material purchased from a local auto supply store under the carbs. The auto performance folks use this to insulate starters etc from extreme engine heat. I attach it to the manifold and carb throat so it forms a "bag" under the carb. Keeps heat away and prevents fuel from running on the exhaust. Easily removed for servicing. I also run the vent tubes into the air filters.

    I can post pics if anyone is interested!

    Take care and be safe. I find the best way to self isolate is IN the HANGER or better yet IN the AIR!


    Cheers
    Don
    Vixen C-FOXK 912UL IVO IFA
    Hello Delta Whiskey
    This pic was in my "profile pics". I hope that I have moved it here correctly. If not just browse through them. Seems like it worked OK (yea)
    Attached Images Attached Images

  6. #16

    Join Date
    Feb 2018
    Location
    Jamul ca
    Posts
    6

    Default Re: 912 uls carb vent lines

    HighWing,
    I really like your solution to this issue, to the point that I acquired the two little funnels after seeing your photo in March. It is now at the top of my short list and was pondering the use of clear drain lines from the funnels instead of the aluminum just for simplicity??
    I see the zip tie holding the vent tube in the little funnel. Does the rigid aluminum tube keep the funnel in place or is it secured somehow next to the carb?

    KF5 w/7 FWF
    First flight, hopefully this year

  7. #17
    Senior Member HighWing's Avatar
    Join Date
    May 2009
    Location
    Goodyear, AZ
    Posts
    1,743

    Default Re: 912 uls carb vent lines

    Quote Originally Posted by Woodymuler View Post
    HighWing,

    I see the zip tie holding the vent tube in the little funnel. Does the rigid aluminum tube keep the funnel in place or is it secured somehow next to the carb?

    KF5 w/7 FWF
    First flight, hopefully this year
    I am away from the airplane, but this photo I found tends to suggest that the funnel is supported by the aluminum tubing and the Zip Ties are there solely to keep the vent tube inside of the funnel.
    Lowell
    Attached Images Attached Images
    Lowell Fitt
    Goodyear, AZ


    My You Tube Channel

  8. #18
    Senior Member Delta Whisky's Avatar
    Join Date
    Dec 2017
    Location
    Amissville, VA
    Posts
    637

    Default Re: 912 uls carb vent lines

    Since the last post brought this subject back into the "New Posts" option, I thought I'd add a picture of what I finally decided to do. Basically I followed the lead of those that routed the line back into the air filter.
    Attached Images Attached Images

  9. #19
    Senior Member
    Join Date
    Mar 2009
    Location
    Summerland BC Canada
    Posts
    411

    Default Re: 912 uls carb vent lines

    Quote Originally Posted by Delta Whisky View Post
    Since the last post brought this subject back into the "New Posts" option, I thought I'd add a picture of what I finally decided to do. Basically I followed the lead of those that routed the line back into the air filter.
    Exactly what I have done now for the past 5 or 600 hours on my 912 UL. Seems to work well.

    Regards
    Don

  10. #20
    Senior Member jiott's Avatar
    Join Date
    Jun 2010
    Location
    Portland, OR
    Posts
    2,959

    Default Re: 912 uls carb vent lines

    Mine are done just like Delta W except I put the hole into the air filter as near the bottom as possible to get as much downslope to the vent line as possible. Been that way for about 900 hrs. The only downside I see to this arrangement is if your carb bowls start to overflow due to sinking floats or excessive vibration you will immediately get a super rich fuel mixture which would cause the engine to run very rough or even kill it. If this starts happening you will get immediate warning, probably on the ground during warm-up. Those engines with Rotax supplied airbox do essentially the same thing with the vent lines-run them into the airbox which feeds the carb intakes, so the risk must be quite small.
    Jim Ott
    Portland, OR
    Kitfox SS7 flying
    Rotax 912ULS

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •