Damn, spoke too soon about fuel shut off...

[Kuda]

Well, I really spoke too soon. I thought I'd solved the fuel shut off problem, but after almost a week of no leaks it's baaaacck...

Here's the deal: after riding, I shut the fuel rod off. Within 2 days, the bottom of the carb/manifold flange starts getting wet, and in another day or so the manifold is full of gas and it's leaking down the back side of the bowl. Bike doesn't have a centerstand (someone thoughtfully hacked off the mounts for it in the 70's and I haven't added them back yet), and it does lean a bit further than typical on the left. If I lean the bike to the right after 4-5 days, I'll get a good cup of gas pouring out of the air cleaner.

Here's what I've done so far (already had one of Cotton's floats, so that's not it):

Reset float level from 1/4" to 3/8", no difference (put it back to 1/4" after this)

Replaced the needle and seat with USA stainless steel needles and brass seats, *three* times. No difference.

Bought alignment tool and aligned tank threads. No difference.

Installed fuel rod shut off with PEEK tip: Worked for about a week, then back to square one.

So the question is, is it reasonable to expect the needle valve be able to hold against a very slight amount of fuel leakage? Or do I really need to pull the fuel rod and see if I can get it to seal up totally? Right now the best I can get it is slowed down to about a drop every 20 minutes or so. Thanks for any thoughts/advice here...

-Kuda
'49 panchop

[Cotten]

So the question is, is it reasonable to expect the needle valve be able to hold against a very slight amount of fuel leakage? Or do I really need to pull the fuel rod and see if I can get it to seal up totally? Right now the best I can get it is slowed down to about a drop every 20 minutes or so. Thanks for any thoughts/advice here...
-Kuda
'49 panchop

Kuda!

No, the floatvalve can never be expected to be absolute.
After all, it is designed to operate open.
I am not aware of the stainless USA-made floatvalve you are using, but even the fine Netherlands valves (with hex needles) benefit from a rap of a wooden screwdriver handle upon a firm tabletop.

The failure of the soft-tipped rod makes one wonder about the condition of the seat.
Please let us know if you observe any damage to the PEEK.

....Cotten

[Kuda]

Cotton,

Thanks for the quick reply! To answer your questions: 1) The needle and seat were purchased online, and reported to be a made in USA part (that's the way it's labeled, any way). The same site also sells billet machined needle valve holders, which I've also installed (they're really nice, BTW). I also have tried installing as delivered, and, once they leaked, using the sharp rap with a plastic screwdriver handle. No difference at all.

When I pulled the fuel valve apart and checked the condition of the tip, it had a very slight ring indentation in it, a full 360 degrees (a fingernail would just *barely* feel the edge of it). I attributed that to my over-tightening it. I can clean up the tip without too much problem, but I'm at a loss as to how to dress the seat of the shut off valve...

-Kuda

[George Greer]

Kuda..

On my WLA here's what I did..

I used a bakingsoda paste that I made up.

It takes a bit of time to completely get the parts to mate up.

My fuel shut off assembly was all aftermarket.

I found out that the two washers were too thick, as well as the spacer.

Replaced them (washers and the spacer) with NOS parts, (the rod and valve is still aftermarket).....polished up the valve and rod with the bakingsoda paste, and installed one of Cottens floats on the M88 set float to spec ..

No leaks. Period, No running over at the carb vent.

It can be made to seal.

George

[Bosheff]

Not to rub it in, but now ya know why H-D did away with that set-up in 66. If yer interested, I've got an OEM shut-off rod and seat I'd probably part with....bosheff

[Cotten]

Kuda..

On my WLA here's what I did..

I used a bakingsoda paste that I made up.

It takes a bit of time to completely get the parts to mate up.

My fuel shut off assembly was all aftermarket.

I found out that the two washers were too thick, as well as the spacer.

Replaced them (washers and the spacer) with NOS parts, (the rod and valve is still aftermarket).....polished up the valve and rod with the bakingsoda paste, and installed one of Cottens floats on the M88 set float to spec ..

No leaks. Period, No running over at the carb vent.

It can be made to seal.

George

George!

Do you mean you lapped the rod to the seat?
Didn't that mean you had to remove and replace the threaded collar upon the rod?

....Cotten

[58flh]

hEY GUYS --NO FUEL-OFF THATS A BAAAD THING! i HAD THE SAME PROBLEM AWHILE-BACK. fIRST OF ALL LETS TALK ABOUT THE FLOAT & SHUT-OFF VALVE(NEEDLE).aLL STAINLESS ONES ARE GREAT WHEN YOUR RUNNING STRAIGHT-UP ALCOHOL, OR NITRO-YOU GET THE PIC.IM NOT SAYING THATS ALL THERE GOOD FOR BUT YOUR REGULAR ONES ARE COVERED IN A BLACK,ORANGE,OR GREY RUBBER-TYPE OF MATIERIAL. THIS STUFF IS CALLED VITRON-COATING. IT IS USED FOR ALL YOUR GASOLINES OUT THERE!-WATCH THAT GASOHOL-STUFF AFTER AWHILE IT WILL EAT THE VITRON COATING AWAY & YOU HAVE A MAJOR LEAKAGE PROBLEM! HOW I FIXED MINE WAS WHAT SOMEONE MENTIONED EARLIER- A GOOD RAP OR 2 FROM A WOODEN-DOWEL WITH THE STAINLESS VALVE-I THEN USED AN 10X-EYELOOP TO SEE IF I HAD A NICE CIRCULAR SEAT-PATTERN ON THE VALVE-IF NOT ANOTHER RAP WONT HURT-ALONG WITH THE PASTE&AFEW TURNS BACK&FORTH! yOU WILL GET A GOOD SEAT EVENTUALLY IT DONT TAKE LONG-20 MIN. OR SO!. ONCE YOU GET THAT NICE SHINY RING ON THAT VALVE -CLEAN EVERYTHING TO THE EAT-OFF-IT-STAGE! PUT IT BACK TOGETHER & YOU WILL HAVE NO PROBLEMS!-HOPEFULLY! AT LEAST THE ONES I HAVE DONE INCLUDING MY OWN & THAT ONES GOING ON 3YRS. NOW!. A LITTLE PATIENCE TAKE YOUR TIME CLEAN EVERYTHING & KEEP IT CLEAN& YOU SHOULD HAVE NO TROUBLE!.(GOOD-LUCK KEEP IT UPRIGHT IN 4TH WIDE-OPEN & ENJOY THAT BAD BIKE) 58FLH

[Cotten]

I stopped lapping needles to seats years ago.

It makes me wonder about these new "stainless" needles and seats.

(The originals were made of Monel metal, which is similar to stainless, but not exactly. And yes, stainless had been invented!)

....Cotten

[PanPal]

Kuda, If the seat in the tank is from V twin check to see if it has been pushed out of position. I had to reseat it and stake it in position on mine.

[Kuda]

Kuda, If the seat in the tank is from V twin check to see if it has been pushed out of position. I had to reseat it and stake it in position on mine.

OK, now THAT'S a new one. Never heard of that before. I'm planning to drain the tanks (again!) this weekend, I'll add that to the list of things to check. Still not sure how to dress that seat, assuming it's not just pushed out like you describe. Can't lap the rod to seat on account of it's not metal any more...

-Kuda

[Cotten]

Kuda, If the seat in the tank is from V twin check to see if it has been pushed out of position. I had to reseat it and stake it in position on mine.

Its been years, but some chromed Tedd kit's seats were a white plastic encased in brass before "captured" temporarily into the housing, and totally doomed to extruding with rod pressure to form an ever-diminishing orifice that leaked anyway.

Original seats appear (with an arthroscope) to be a pressed-and-staked-in (from the top) solid brass insert.

Please note that whether a floatvalve or a petcock seat,
brass tends to embed abrasives, thus making lapping little more than an inspection exercise.

....Cotten

[Hubbard]

You won't want to hear this but this is how I fixed mine. I made afitting to screw into the tank that will accept a pingel petcock (1/4-18 pipe), then went to Napa and looked thru rebuild kits for a Holley or whatever and found a Viton tipped needle that would fit the inlet valve in an m-74. I drilled and tapped a hole for a 2-56 screw in the upper end of it and fit it up.50 some thousand miles and no worries. Stock oem is nice but personally I would rather ride. And besides if you're running chinese shit from teddy the queer didn't you kinda defeat the purpose? And to save yourself a lot of headache purchase a Mitee Vac brakebleeder and test it on the bench, marvelous tool.

[Cotten]

You won't want to hear this but this is how I fixed mine. I made afitting to screw into the tank that will accept a pingel petcock (1/4-18 pipe), then went to Napa and looked thru rebuild kits for a Holley or whatever and found a Viton tipped needle that would fit the inlet valve in an m-74. I drilled and tapped a hole for a 2-56 screw in the upper end of it and fit it up.50 some thousand miles and no worries. Stock oem is nice but personally I would rather ride. And besides if you're running chinese shit from teddy the queer didn't you kinda defeat the purpose? And to save yourself a lot of headache purchase a Mitee Vac brakebleeder and test it on the bench, marvelous tool.

Hubbard!

That's a lot of machinework and ca$h when you could have just wrenched a common valve in the line.

GASVLV.jpg (53.59 KiB) Viewed 3720 times

And wow you must know Tedd better than the rest of us,
Did you do time together, or what?

....Cotten

[Hubbard]

Tried one of those, just another bandaid. How do you figure it's a lot of machine work ? How many times did he have the tanks on and off? And yea me and teddy were indeed intimate, I was one of his dealers about 15 years ago. He screwed me every time I picked up the phone. Everytime I hear "V-TWIN" my ass cheeks slam shut.

[fourthgear]

Tried one of those, just another bandaid. How do you figure it's a lot of machine work ? How many times did he have the tanks on and off? And yea me and teddy were indeed intimate, I was one of his dealers about 15 years ago. He screwed me every time I picked up the phone. Everytime I hear "V-TWIN" my ass cheeks slam shut.

I almost fell out of my seat laughing !