78 GS750 Petcock

[The1970's]

I had thoughts to sell my GS750 to make room for a CBX that a friend of mine decided to sell...well the GS must have knew what was going on because I washed it, and while I had it idling and drying it off I noticed a strange noise from the petcock. Long story short the vacuum diaphragm has started leaking and created a vacuum leak. I confirmed with my wideband o2 that it is leaner at idle with the vacuum line connected.

So what is the best way to replace the petcock/diaphragm? I have heard of others having trouble with rebuild kits, but have also heard that ebay petcocks seem to be of good quality and last a long time. I don't mind buying an OEM petock, but saving a few dollars never hurts if it doesn't sacrifice quality. On the other hand, mine is still functioning properly it just needs a new diaphragm. Has anyone found a source for just a replacement diaphragm?

[tom203]

Manufacturing methods change over time, so replacement petcock internals tend to be slightly different from 40 year old ones. Best to just get new unit and not have your buyer surprised by leaking gas.

[Gorminrider]

on ebay, there's georgefix's store. Match your petcock very carefully as there are many differences amongst petcocks.

http://www.ebaystores.com/GEORGEFIXS-MOTORCYCLE-PARTS

[The1970's]

on ebay, there's georgefix's store. Match your petcock very carefully as there are many differences amongst petcocks.
http://www.ebaystores.com/GEORGEFIXS-MOTORCYCLE-PARTS

All of the petcocks on his store that are listed for a GS750 have different outlets than mine. When looking directly at the petcock from the left side of the bike both the fuel outlet and vacuum inlet are on the left hand side. Is that factory or is it possible mine has been changed before? Maybe I will just go ahead and order the factory unit from Suzuki.

[GSXR7ED]

Good call...buying a new OEM petcock.


Ed

[hannibal]

All of the petcocks on his store that are listed for a GS750 have different outlets than mine. When looking directly at the petcock from the left side of the bike both the fuel outlet and vacuum inlet are on the left hand side. Is that factory or is it possible mine has been changed before? Maybe I will just go ahead and order the factory unit from Suzuki.

Pretty sure you have the factory petcock. Mine was oriented that same way.