petcock vacume check valve 82 gs850glz

[Anonymous]

in the fuel petcock, in the vacume diaphram area, there is a small disc with 4 holes in it that vacume draws thru . on the other side of this disc there is a rubber flap acting as a check valve only allowing airflow (vacume) to flow in one direction. i melted the rubber disc with carb cleaner and it is gone now. after cleaning rubber out of that area i tested the petcock fuel flow and it works as usual. i created vacume by sucking on the hose. my bike is apart so i havn't run it yet. my question: when the engine backfires or if it sends a burst of air backwards through the vacume line into the diaphram, being that that burst is now unrestricted without the rubber check valve, am i going to have problems? thanks for help

[SqDancerLynn1]

It sounds like you will have problems. with a bad diaphram the engine will suck fuel excess fuel into the #2 cylinder and you have no way for the fuel to be turned off.
ONE of the basics of repair is to HAVE A PROPERLY WORKING FUEL VALVE it will effect other aspects of the bike and can make it dificult to get the bike to run properly

[Anonymous]

petcock diaphram

my diaphram is fine, and the petcock works fine. the problem is with the rubber check-valve that is attached to the small disc with the 4 holes in it (to the right of the diaphram itself, housed in the right cover). . without the rubber check valve, which will now allow reverse pressure(if there will be any??) to push the diaphram in the opposite direction(the direction of the spring pressure), i want to know if that opposite direction pressure(which may come from backfiring,etc..), hitting the diaphram will hurt it. a backfire(which these bikes do) will be a strong blast going directly to the diaphram(i believe) now that the rubber check-valve is missing. to best understand this dilemma, the disc & rubber check-valve(not the diaphram itself) must be understood.thanks

[moto_dan]

Re: petcock diaphram

my diaphram is fine, and the petcock works fine. the problem is with the rubber check-valve that is attached to the small disc with the 4 holes in it (to the right of the diaphram itself, housed in the right cover). . without the rubber check valve, which will now allow reverse pressure(if there will be any??) to push the diaphram in the opposite direction(the direction of the spring pressure), i want to know if that opposite direction pressure(which may come from backfiring,etc..), hitting the diaphram will hurt it. a backfire(which these bikes do) will be a strong blast going directly to the diaphram(i believe) now that the rubber check-valve is missing. to best understand this dilemma, the disc & rubber check-valve(not the diaphram itself) must be understood.thanks

I sent you a PM before I read this last post, but now I'm confused. :?

[moto_dan]

I'm not sure the part you're referencing is a check valve, but I'm sure someone on this site knows. Check out the following link. http://www.crc2onlinecatalog.com/petcock_rebuild.htm cursor down to find the valve that you have. I'm curious