VST Shrader valve

2006 250 HPDI. There is a schrader valve on the top of the VST mine is leaking quit a bit. There is no part number for this in the yamaha parts book or I would just buy one. I removed it to work on it and that was a big mistake. It is a pressed in fit. Strange thing is that it has a rubber O ring in a groove on the end of it. You would think it was serviceable. Any way if I can find new guts for it that will work what would I seal this with. The O ring is there to hold the gas pressure 30 lbs at the vst I think. The valve is brass pressed into Aluminum. I am concerned that in removing it I will have loosened the pressed fit. I am sure I can tap it back in but will it hold 30 PSI. I don't want a trial and error here because it will get worse every time I try something. Any one ran into this?

Re: VST Shrader valve

The schrader valve is made into the 'float chamber cover', not a separately listed part....price on cover is 526.45. I would fill and then drill the hole to accept a valve stem, cut and threaded on end, with matching threads in cover....and a high pressure valve core installed in stem like a compression tester would have in it(NAPA, few dollars for several), this is more like 42 psi minumum or 48, can't recall right now, not 30. A little work for sure....but 526.45 is kinda steep, too. Good luck. Plan B would be just do away with the valve....you don't need it except to test fuel pressure, which YDS can do anyway, and all Yamaha dealers have it....

Re: VST Shrader valve

I got lucky. I found a stainless set of guts that fit perfectly. I still had a tight fit so I used a dab of red locktight and popped it back in. Pressure tested good. The O ring was is good shape so I am hoping it holds up.