'81 GS1000G fuel petcock

[KiwiGriff]

IMG_0303.jpgI know, I know.... I wish I'd read the posts on fuel petcock replacement BEFORE I got a parts kit from the US but......i'm not sure why only 10-15% of rebuilds are successful. Seems so simple! I bought a new non-OEM fuel petcock which leaked from new. Got my money back and thought I'd re-install the old one but with new parts (due to a wet No. 2 plug - coil replaced and new plug caps fitted and still mis-firing. I know about the vacuum pipe dropping fuel into No. 2 cylinder). Could someone confirm something for me though please? On my original petcock there is a hole in the casing that isn't there on a cheaper non-OEM petcock. I was cleaning the body of it and used a dental pick to scrape away some of the crud. I poked the dental pick in this indentation and next minute a hole appeared (I thought it was just gunge in a hole as it's perfectly circular). The diaphragm has a hole in it matching this hole in the casing which I've aligned it to. Unfortunately fuel is still pouring out with the tap in the 'On' position. There was no new spring in the parts kit (which I thought it might have). Think this might be the issue? or is it because I perhaps created a hole in the casing that may not have meant to have been there?! Everything went together smoothly - there are no kinks in the diaphragm and it looks as though it should function as intended. The seat where the diaphragm locates looks to be in good condition. Perhaps I should have used some teflon grease on the o-ring? Appreciate any thoughts. (Original is on the left with the non-OEM faceplate on - hence its brightness) Cheers Griff

[KiwiGriff]

Had the plastic 'gasket' the wrong way around between the two parts of the diaphragm so it couldn't move! Put it back together and thought I'd fixed it - no fuel leakage for the ten minutes I had the tank sitting off the bike. Put the tank back on, started her up and very (very) soon started running roughly again. Shut it down to remove the tank - took the hoses off and fuel started flooding out of the bloody tap outlet again! Have bitten the bullet and ordered a new complete unit at exorbitant cost - but if it fixes the issue and means I can ride the bike again I'm happy!

[tom203]

Well, I need to know where you got this faulty non-oem petcock! Here's a pic of my original that I replaced with a non-oem six? years ago that looks similar, but casting finished is improved over original - still works fine

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[850 Combat]

One of my 1980 1000G has a petcock from a 1982 GS850/1100G. I can't remember if it is OEM or aftermarket from Z1 enterprises. I had to modify a little to make it work. Some filing, as I recall. The vacuum line and fuel line routing isn't as nice as OEM. My motivation was lowering the cost of replacement. It has been on there a decade or so, and I don't remember precisely what I had to do to use it.