GS850 wont run without choke on

[dbarnes42]

I did replace the intake boots and the orings, the airbox is attached with a new filter and boots on it, the valves have been adjusted, I did put new o rings in the carbs and it has a stock exhaust. The fuel flow from the petcock is good if it is on prime. But I attached a hose to the vacum side of the petcock and sucked on it and the flow was not so good. Could it really be something as simple as the petcock?

[mike-s]

id drain the tank, take the petcock off and take it apart and give it a good once over, it could be something as simple as the vacum o ring sticking. If it turns ot to be something with the petcock you can get replacement seals and o rings easily enough.

[Big T]

Could it really be something as simple as the petcock?

Yep - start by draining the tank, then removing the screws on the face of the petcock. Pull the lever out and see if there's crud back there.

If it's pretty clean, pull the petcock from the tank and check the filter screen for crud.

If it's crudded up, apply carb clean as needed. You'll probably want to replace the O ring and disc after you've pulled it apart, but you can always do that later.

Don't take the diaphragm apart.

If it's clean at both places, buy a new petcock. Rebuilding has a low success rate, including mine, so why toss $20+ bucks to get a failure when a new one is about $50?