Air Box Full Of Petrol

Discussion in 'Bonneville' started by T0pcat, Apr 26, 2021.

  1. T0pcat

    T0pcat Member

    Oct 24, 2018
    44
    18
    UK
    #1 T0pcat, Apr 26, 2021
    After a long rideout, yesterday, I couldn't start my bike this morning. I found the airbox full of petrol. No obvious signs of leaking from the fuel line or carbs. Where's it coming from?
     
    • Disagree Disagree x 1
  2. Mischa Vladivostok

    Mischa Vladivostok Well-Known Member

    Feb 9, 2015
    234
    93
    Dublin, Ireland
    #2 Mischa Vladivostok, Apr 26, 2021
    Crankcase breathing? Check your oil level, if it is higher than the norm, it might be spitting some oil into the airbox.
     
    • Useful Useful x 1
  3. T0pcat

    T0pcat Member

    Oct 24, 2018
    44
    18
    UK
    #3 T0pcat, Apr 26, 2021
    It's definitely petrol in the airbox but I'll check the oil as I'd hate to think the oil is contaminated with petrol and from the level of the petrol in the box, it's a distinct possibility. Thankyou for reminding me about the breather.
     
  4. T0pcat

    T0pcat Member

    Oct 24, 2018
    44
    18
    UK
    #4 T0pcat, Apr 30, 2021
    Update, Changed oil and filter,, dried out the air box. ran the engine. Last night the airbag was full of petrol again. This time the bike was on its vnre stand, The carbs are angled towards the engine so I would expect fuel to fill the inlet tracts, if it were a carb problem, but no. The tank is good and the petrol tap is new. The carbs were recently removed and thoroughly cleaned before re-assembly. If I HAVE to I'll get them off again, but it's a rotten job and if I can avoid it, any hints would be good
     
  5. Ducatitotriumph

    Ducatitotriumph Crème de la Crème

    Apr 25, 2019
    2,187
    1,000
    Rothwell
    #5 Ducatitotriumph, Apr 30, 2021
    Is it oil and petrol or just petrol?
    Piston rings?
     
  6. Cyborgbot

    Cyborgbot Guest

    #6 Cyborgbot, Apr 30, 2021
    Last edited by a moderator: May 1, 2021
    Don’t know if this comment will help, but if you put a tube from the air box back into the petrol tank, you’d inadvertently invent a perpetual mention (motion) engine.

    Just saying…
     
    • Funny Funny x 2
  7. ThruxM

    ThruxM Member

    Mar 17, 2017
    29
    18
    Avon
    #7 ThruxM, Apr 30, 2021
    I'd say carb float valves not sealing or a dodgy float. Either punctured or jamming. Perhaps check by blowing into the carb fuel line before pulling apart.
     
    • Agree Agree x 1
  8. Sam G

    Sam G New Member

    Feb 1, 2021
    2
    3
    Medina ohio 44256
    #8 Sam G, Apr 30, 2021
    My air box is full of oil and is dripping out of a hose like an overflow hose
     
  9. Sam G

    Sam G New Member

    Feb 1, 2021
    2
    3
    Medina ohio 44256
    #9 Sam G, Apr 30, 2021
    My airbox on my 955i is full of oil dripping out of the what looks like an overflow hose what could be my issue I might have had too much oil in it but now it's coming out real fast only when it's running here are some pics please help it won't let me post anywhere else on this page for some reason
     
  10. Sam G

    Sam G New Member

    Feb 1, 2021
    2
    3
    Medina ohio 44256
    #10 Sam G, Apr 30, 2021
    20210430_175256.jpg

    20210430_175302.jpg
     
  11. Yorkshireman

    Yorkshireman Crème de la Crème

    Dec 12, 2015
    3,405
    1,000
    Barnsley
    #11 Yorkshireman, May 1, 2021
    Or even perpetual motion.



    Just sayin;)
     
    • Funny Funny x 2
  12. Ducatitotriumph

    Ducatitotriumph Crème de la Crème

    Apr 25, 2019
    2,187
    1,000
    Rothwell
    #12 Ducatitotriumph, May 1, 2021
    piston rings or cylinder liners. I had the exact same on the ducati.
     
  13. Cyborgbot

    Cyborgbot Guest

    #13 Cyborgbot, May 1, 2021
    That too.

    If it were a HD engine the owner would perpetually mention it.
     
    • Funny Funny x 1
    • Agree Agree x 1
  14. T0pcat

    T0pcat Member

    Oct 24, 2018
    44
    18
    UK
    #14 T0pcat, May 3, 2021
    Last edited: May 3, 2021
    For anyone with this problem, the first port of call is the oil level in the crankcase. Don't ask how I know......
     
Loading...
Similar Threads - Air Box Full
  1. Cihan

    Thruxton Thruxton Rs Airbox Removal

    Cihan, Sep 29, 2025, in forum: Thruxton, Scrambler & Trident
    Replies:
    4
    Views:
    722
    Cihan
    Oct 3, 2025
  2. Mark TGR9

    Thunderbird 900 Air Box

    Mark TGR9, Aug 27, 2025, in forum: Technical Help
    Replies:
    6
    Views:
    1,204
    Mark TGR9
    Aug 30, 2025
  3. Norfolk Scram

    Air Box Removal K&n Pod Filter Hole.

    Norfolk Scram, Jan 11, 2025, in forum: Technical Help
    Replies:
    3
    Views:
    902
    joe mc donald
    Jan 13, 2025
  4. JayB5UK

    '04 S3 Airbox Question

    JayB5UK, Nov 19, 2024, in forum: Speed Triple
    Replies:
    1
    Views:
    660
    JayB5UK
    Feb 2, 2025
  5. tc80211

    '71 Bonneville 650 Airbox Alignment Off From Carb

    tc80211, Dec 12, 2023, in forum: Vintage Classics
    Replies:
    9
    Views:
    2,156
    tc80211
    Dec 22, 2023

Share This Page

Sign up