Does a petcock have spring inside?

[tokarz33]

Does a petcock have spring inside? I ask because I have an extra spring on my work bench.

www.yamaha-motor.com does not show a spring.

Thanks,
Andrew

[John]

They have a wavey spring/washer, but no coiled spring.

[tokarz33]

Cool, thanks. I better save that spring.

[John]

hey tokarz

Where is Lucas?

[tokarz33]

on 1378, 4-5 streets south of the lucas food mart. been out here before?

[TopCatGr58]

Hey Andrew,

If that spring is fairly small...like the diameter of a "bb" and evenly round like a cylinder, then it belongs behind your choke lever ROD in the carb body, it's used with that "bb" for the detents on the choke lever!
T.C.

[tokarz33]

Bingo!! Maybe that is why my chock does not stay open.

Carbs are all rebuilt. Bike started up no problem. I was surprised. Engine has a cool sound.

Tomorrow night I will synch the carbs. All that is left is restoring the rusty tank.

[prometheus578]

petcock spring

Petcock DOES have a spring. Goes by the vacuum diaphram. Spring holds the diaphram plunger forward to stop fuel flow till vacuum suck diaphram and plunger back to open flow.
The sandwich is: petcock assy, plunger and diaphram gasket, plastic block, diaphram, spring, and then the back plate with vacuum hose nipple.
Unless you have a special... I don't know what they look like.
(I tried the link to see the pic, but I couldn't get it)

[tokarz33]

I do have two springs. One from the carbs and I was pretty sure this other one came from the petcock. Parts diagrams do not show the spring though.

[John]

Oops

I didn't realize that you rode a standard. I was refering to a Special. Sorry 'bout that.

[tokarz33]

Thanks. I still have two springs. One for the carb and one for something else. This is so much fun.

[Ken Talbot]

The standard petcock does in fact have a spring inside. It is approximately 1/4" diameter by maybe an inch or so long. It goes on the dry side of the diaphragm to push the sealing o-ring against a seat to shut off fuel flow when there is no vacuum.

[tokarz33]

Ok guys, I am getting mixed signals. Which is it? Could someone check their manual?

[Ken Talbot]

Prometheus and I are talking about a petcock on a Standard - it definitely does have a spring. John was talking about a petcock on a Special - it definitely does not have a spring.

Which model do you have?

[tokarz33]

81 xs1100 H Model

standard right?