Leaky Fuel petcocks

[Peter Cooke]

One of the European dealers was advertising petcocks that they guaranteed not to leak.

[montij]

I’ll take a look for those. Today I spent a lot of time attempting to repair the ones I have. I lapped them lightly by hand with grease mixed valve grinding compound and then used toothpaste. These were the only materials I had available. Afterwards I added washers for a much tighter fit. Have not tested them with fuel yet. I have 4 petcocks in total 2 originals and 2 from VTwin. All I really need is one reliable one to use on the main right side tank.

[montij]

As Merdog1968 mentioned, I also use Viton Flouro. Brown O-rings in petcock valves to stop fuel leakage. I've Been using them well over 25 years now and they work great. However ,They do need replacement overtime like any O-ring, Gasketing material or seal.
Duke

I don’t have the machining ability to machine the groove for the o rings you mention. Amateur enthusiast here.

[montij]

O rings stop valve from dripping ,but gas will still not completely shut off. A little EZ-Turn on valve before assembly helps.

I had not heard of this product before.
Thank you for mentioning it I’m going to buy some.

[Rich Simpson]

Lather the peacocks up with Easy turn lube..

[Iacovos]

Dear fellow members,

Is there any progress on this? I mean has any of you formulated a procedure to leak proof the early petcocks? My left one leaks, bought a new pair repop from Europe. After some time still leaks. I have sent the older ones and had them lapped/fixed but still have them in the box.

Does this EZ Lube work? How do you apply it? Inside the tapered petcock surface? Does it risk being drawn in the carb?

Thanks for your input

[Omarttentmaker]

I don’t have the machining ability to machine the groove for the o rings you mention. Amateur enthusiast here.

As quoted somewhere in this thread, wouldn't there have to be two grooves, one on either side of the hole in the male tapered piece? And when you cut the grooves in, is the tool oriented parallel to the axis of the part, or perpendicular to the taper? And how do you determine how deep to cut the grooves? Unless you can figure out a way to locate the cut exactly on a specific spot on the diameter of the taper, the sizing for the o-rings bacomes a crap shoot.

[montij]

Dear fellow members,

Is there any progress on this? I mean has any of you formulated a procedure to leak proof the early petcocks? My left one leaks, bought a new pair repop from Europe. After some time still leaks. I have sent the older ones and had them lapped/fixed but still have them in the box.

Does this EZ Lube work? How do you apply it? Inside the tapered petcock surface? Does it risk being drawn in the carb?

Thanks for your input

I have applied the EZ lube liberally to the plug and made sure there was non in the open passage after reinstalling.
I have had no leaks whatsoever. I should mention I did lap in these petcocks with valve grinding compound and toothpaste manually and then added a washer under the spring to draw everything in tighter.

[Iacovos]

i have applied the ez lube liberally to the plug and made sure there was non in the open passage after reinstalling.
I have had no leaks whatsoever. I should mention i did lap in these petcocks with valve grinding compound and toothpaste manually and then added a washer under the spring to draw everything in tighter.

thanks for you reply!

[Iacovos]

Well I must say....finally managed to get the EZ lube shipped to me....tried it on my 36 EL left petcock...and the leaking / weeping has stopped...

I did not even lap with compound or toothpaste...just the lube

This lube is amazing!

Would highly recommend it to anyone with the 36-39 OHV petcocks...

THANKS

[scooterscum61]

I had the same problem Tomfiii has it right after lapping in, EZ turn aircraft sealant lubricant is the ticket Its designed for conical fuel valves does not dissolve with even high-octane fuels. I added a small washer to increase the spring tension slightly. valves turn smoothly and have had no leaks or seepage. They were driving me nuts, everything else I tried would fail.