1978 GS550 petcock??

[Anonymous]

I have a question about the petcock on my 550 I see ON I see PRI I see RES when I put the lever to pri I can blow air through when it's on res I can blow air when it's on ON no air is this right or is it in need of rebuild. This is a new bike to me and I am trying to get her going I have started it but have used an aux gas source, now I'm ready to put the tank back on and take it for a ride. Thanks for your help Steve

[earlfor]

Re: 1978 GS550 petcock??

NOrmally, with the vacuum operated petcocks, run and reserve are vacuum operated and prime bypasses the vacuum function. So with it set to prime, you would be able to blow air through. With it set to run or reserve, the diaphram should be closed when the engine is not running and you should not be able to blow air through.

Earl

I have a question about the petcock on my 550 I see ON I see PRI I see RES when I put the lever to pri I can blow air through when it's on res I can blow air when it's on ON no air is this right or is it in need of rebuild. This is a new bike to me and I am trying to get her going I have started it but have used an aux gas source, now I'm ready to put the tank back on and take it for a ride. Thanks for your help Steve

[Anonymous]

Thanks, how do I know when it needs rebuilding?? IF it needs it.

[earlfor]

(best done with nearly a full tank of gas)

If the petcock seeps any fuel when set on run while sitting in the garge overnight, it is faulty. An easy way is to park the bike, shut it down, leave the petcock on run. Pull the fuel hose off the petcock and put a hose on the petcock long enough to reach into a small container sitting beside the bike. If there is anything in the container in the morning, you have a problem. :-)

Earl

Thanks, how do I know when it needs rebuilding?? IF it needs it.

[Anonymous]

Thanks Earl for all your help. I need lots I'm sure...LOL... This is a great place and the people are great!!!!

[earlfor]

Ask away. We couldnt have a tech section if no one needed anything. LOL

Earl

Thanks Earl for all your help. I need lots I'm sure...LOL... This is a great place and the people are great!!!!