Petcock Replacement

[Larrym]

Red, White, or Blue?

What color/brand of teflon tape?

As long as I'm going to do some more "unsanctioned science tests" I might as well get a roll of what you used and throw it in with the rest.

Gas versus teflon tape: the fight of the century!!

[dbeardslee]

I just used the stuff from the plumbing section of Ace Hardware/Motorcycle parts. I've also used it on brake fittings, and prior to that I did with brake fluid what your going to do with gasoline. Brake fluid is a nasty solvent, and it didn't touch the teflon. After a week it showed no signs of deterioration, so I used it. It has been doing it's job for a couple years on the brake fittings with no leaks. It'll be interesting to see what happens after immersion in gas.

[Larrym]

White it is....

Cool. Same white stuff I have already.

Used brake fluid as a penetrant at the auto shop I worked in. Never threw it away when we drained or bled a system. Saved it and put it in spray bottles to apply to rusted/corroded nuts or bolts. Flammable though. Made things interesting when we had to use a torch and use heat to break things loose when the brake fluid failed to loosen things.

I'll put the glass bottle next to the one where I mixed the DOT4 and DOT5 brake fluid. That's looking quite promising as far as WTF would happen if you did that in your MC.

[MrOzz]

LarryM,

Do you get air bubbles in your fuel lines? I have mine routed so the fuel line goes down. Then back up. Then down into fuel filter, then into carbs. I always have a air bubble in the top part of the fuel line. Here is a drawing. only one side shown.



Thanks for the info.

Ozz

[Larrym]

Air "Embolism"??

MrOzz,

No. Don't have that routing method. If I did then I'd be just as concerned about that air bubble as you are. Herein lies the potential for the dreaded "Vapor Lock" where your shiny bike dies at the intersection, won't start again, and the other drivers snicker while you push it off to the side. "Get A Harley!! Honk! Honk! HAhaha!!"

Either you were born on Krypton and unlike the rest of us on planet earth, have X-ray vision to see through ordinary fuel lines, or you're using those newer transparent/translucent fuel lines like I am using.

My lines go down as directly as possible from the petcocks then they loop under the carbs where I have those big honkin' filters, then they connect to the opposite side fuel Tee for the carbs. The fuel Tee is pointed down not up. This routing allows any small fuel bubbles to work their way up to either the petcock or the fuel Tee where they can die silently in great numbers while I drive. (Not that I'm insensitive here...they either die in small numbers over time or in your routing live on to gather and cause the engine to die...)

I'm torn between putting some kind of leather cover over the filters at the bottom of my fuel loops. I mean my arrangement would lose points in the beauty contest. But then the filters wouldn't be exposed to the cooling effects of the air and any bubbles who found their way inside the filters would be there to stay and when the heat rose high enough, the bubble would expand leading to that awkward moment where the bike dies at the intersection.

Not while I'm behind that pick-up truck with the PYT's in the back!! No no NO. They were just about to ask me to follow them to the pool party!!

[boyat68]

MrOzz:

I would think that the way the fuel tower strainer is built (the ones in the tank), you would get some air into the fuel lines as the towers are uncovered with half a tank. It seems to me that the fuel would gurgle, letting in air just as emptying out a jug does to equalize the pressure. Of course the cap vent should equalize the air and prevent it. I do get small bubbles in my fuel lines visable when the bike is running, but does not seem to cause a problem. It maybe as simple as the vent is not letting in sufficent air. Should consider checking the vent.

[MrOzz]

...Either you were born on Krypton and unlike the rest of us on planet earth, have X-ray vision to see through ordinary fuel lines, or you're using those newer transparent/translucent fuel lines like I am using...

LarryM,

One of the two is correct. Sorry I cannot tell you which one is. I bet your a smart one and can figure it out. LOL

Ok I am going to change my fuel routing. See if that does anything for me. I never had the bike die but I was gettting a fail to launch. The fail to launch went away when I changed my coils. Now I am wondering if this was also causing the issue.

BTW I like the humor in your replys.


boyat68,

I have checked and cleaned the vent.

Thanks for the thought.


I wrote Mikesxs a e-mail. Seeing if they will give me some info on thier fuel petcocks. Mostly what the hole spacing is. If I remeber correctly on the special tank its 33mm or 34mm. I just have to remessure it.


Ozz

[MrOzz]

I heard from MikesXS.

The petcocks part # 20-0050 and 20-0051 are 43mm center to center. O well I guess I cannot use them with out some major mods.

Ozz