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General Information => Troubleshooting => Topic started by: guy plain on July 22, 2011, 05:14:26 pm

Title: one more air fuel fix
Post by: guy plain on July 22, 2011, 05:14:26 pm
 ive bwwn chassing the air in my fuel system for two days.....read alot of post on here and never heard of this..loosen off the fuel cap...i went over every conection...new clamps..new hoses under hood..new filter...finaly got feb up and put compressed air down the fuel lines hopping to force a leak....but the tank pressured up...and held it...(only a few psi)...cracked the fuel cap and released the pressure..hooked every thing back up...with in a minute there was no more air in the system....guess the vacume built up in the tank was forcing air in some place...now to find the tank vent and clean it lol
    hope this helps some one...wish i had known about it 2 days ago lol
Title: Re: one more air fuel fix
Post by: 8v-of-fury on July 22, 2011, 07:45:31 pm
Should an atmospheric vented tank pressurize? I thought they shouldn't.. ??
Title: Re: one more air fuel fix
Post by: rabbitman on July 22, 2011, 07:50:19 pm
Quote from: 8v-of-fury on July 22, 2011, 07:45:31 pm
Should an atmospheric vented tank pressurize? I thought they shouldn't.. ??

He's saying the vent is plugged so fuel drawn from the tank causes a vacuum which would let air INTO the system at every possible leak.
Title: Re: one more air fuel fix
Post by: Patrick on July 23, 2011, 04:28:05 am
Is the vent in the cap? try a new cap.......
Title: Re: one more air fuel fix
Post by: the caveman on July 23, 2011, 09:13:20 am
Quote from: Patrick on July 23, 2011, 04:28:05 am
Is the vent in the cap? try a new cap.......
that looks to me to be the logical conclusion
Title: Re: one more air fuel fix
Post by: rabbitman on July 23, 2011, 12:57:20 pm
My bunny doesn't vent in the cap, its got a separate hose running all the way up front and into a hole in the frame rail........at least I think that's what it is.
Title: Re: one more air fuel fix
Post by: guy plain on July 23, 2011, 02:35:04 pm
that would make sence ...i was doing some driving on muddy roads...the underside looks like a barren garden lol
Title: Re: one more air fuel fix
Post by: ORCoaster on July 24, 2011, 05:24:47 pm
My 81 vents the same.  When I noticed bubbles in the line I put a vacuum on the line first to suck out any goobers and then applied air and listened at the fill tube for bubbling noises.  All clear and then no more in line air.