Petcock Leak in the Off Position

[skids]

(snip) If you disassemble the petcock, between the switch and the main body there's a little plastic circle with 4 holes in it. I'd take a close look at that. It might look ok at a quick glance, but if any of the edges on those holes are rounded over a little bit, it could be your culprit.

If you are going through the trouble of replacing the holey gasket, you might think about working on the valve handle face. They are a little rough from the factory. I took mine and sanded them smooth with fine grit wet-n-dry. Following that, take the sharp edges off around the holes. Then, polish the surface with Mothers Milk, Eagle One, or what ever. I am certain that it will make the holey gasket last longer (maybe forever). PS, there is a Right and a Left handle on the standards and you can't mix them up and expect them to operate correctly!

[crazy steve]

But the real question now, is about my idle mix screws. The wear on all of them is significant. Are they somehow repairable or do I go straight to replacement.

The left one looks serviceable, but that right one has seen better days... I'd replace....

[Shacknasty]

Thanks for the sage advice. Those are some high-quality tips y'all is droppin' on me! I'll pay close attention to the petcock and do a little clean-up work on the petcock handles. I found out about the non-interchangeability of those handles, but I appreciate the reminder!

Steve, if I'm gonna replace one, I would just as soon replace all four. That wear can't be good for A/F metering. I'm gonna check with some local bike shops and see if I can find replacements.

[DGXSER]

I've only had one set of the early carbs, but it seems like the tips were tapered at the end like that. Is it the light that is making one look so much different than the other? almost looks like a shadow effect.

[natemoen]

Those are f'ed up! They are supposed to be straight and smooth all the way to the tip. Replace them!

[unicorncomputer]

If you didn't know I will tell you. To test the brass floats boil some water and then take the water off the stove. Completely submerge the float in the got water. If there are any leaks you will see a stream of bubbles coming out of the hole.

Why not just use cold water to test for stream of bubbles?

[DiverRay]

The hot water will cause bubbles to rise faster. The temp difference between the cool floats and the hot water does it. The cool air inside the floats will expand and cause bubbles to come out of any hole.

[natemoen]

Why not just use cold water to test for stream of bubbles?

It's physics young man!

Ray has it covered.

[fredintoon]

What the hell is a "Physic" anyway?

Hi Shacknasty,
I'm late to the fair on this one, but "Physic" is an obsolete term for bowel-opening medication.
But from context I'd suppose he meant "Psychic"?
But about the mysterious gas leakage.
Your profile sez you have a Standard and their gas taps don't have a true OFF position. The vacuum operated ON mode has been known to occasionally stay ON after the engine stops and then fix itself which is perhaps why you can't find anything wrong with them.
BUT
The carb float valves should stop the fuel overflow anyway, right?
Looks to me like you have two problems, eh?

[MPittma100]

Gas in Oil

No problems at all on the last ride. I'm sure I woulda noticed the smell of gas and there is no sign of leakage below the carbs. The airbox was fulla gas though.

We'll see.

It is a good idea to put a block (2 X 4) under the front tire when the bike is parked for extended periods. This will put any leaking gas into the air box while keeping it out of the crankcase.

It would be almost impossible for gas to get past a petcock in the off position (Specials only) if the petcock seals are good. The petcocks shut the gas off going to the octy, but a leaking float valve(s) could allow fuel already in the octy and lines to leak into the oil. More likely (as suggested) fuel was getting in the crankcase at some point when the petcocks were in the on position.

Bottom line is that a problem exists that needs to be repaired - rebuild carbs, petcocks, octy. Hook up a remote fuel source to carbs prior to installation and verify no leakage.