HarleyTechTalk

Technical Forums => EVO 1340 => Topic started by: Harpo on April 06, 2020, 10:30:07 AM

Title: CV issue
Post by: Harpo on April 06, 2020, 10:30:07 AM
Carbed '97 RK - Bike sat for about 4 weeks with no fuel in bowel, and after that it had a healthy trickle out the overflow tube.  Tore carb off and replaced needle, checked the seat (it's good), set float and re-checked a coupla' times, tried setting float a bit on the low side, but I'm still getting a little bit of a trickle out the overflow tube.

I've looked it over real good and see nothing wrong.  Anyone ever ran into this?  TIA
Title: Re: CV issue
Post by: Hossamania on April 06, 2020, 11:33:53 AM
Look closely at the seat for pitting. I'm sure you checked, but is the float leaking?
Did you spray everything down, especially the needle and seat, with some cleaner?
Also, when is that last time the whole carb was cleaned and serviced? I tend to replace the accelerator pump and clean those passages whenever I have it apart if it's been a few years. (And clean the accelerator rod, they tend to get dirty and bind.) Check for full travel to the stop for the throttle. Just some things of the other things I look at when servicing.
Have you tried running it to get a healthy flow of fuel to run past it? Is your petcock working properly? Not necessarily related, just curious, I turn mine off every time to prevent a leak like yours from becoming a big problem.
Title: Re: CV issue
Post by: Hossamania on April 06, 2020, 11:35:18 AM
One last thing, where did you get the needle, HD or aftermarket? Is the tip in good shape, rubber not hard?
Title: Re: CV issue
Post by: thumper 823 on April 06, 2020, 11:40:57 AM
Does gas flow out the fuel line with petcock open?
Title: Re: CV issue
Post by: Hossamania on April 06, 2020, 03:55:24 PM
Quote from: thumper 823 on April 06, 2020, 11:40:57 AM
Does gas flow out the fuel line with petcock open?

And is it the original vacuum operated petcock or an aftermarket?
Title: Re: CV issue
Post by: Diver625 on April 06, 2020, 06:31:34 PM
How old is the fuel line, the old ones decompose and pieces flake off of the inside and get stuck holding the needle open a bit. The first thing to do is shut the gas off and run the bowl out of gas. Then turn it back on and try it. When the bowl is out of gas the float drops down and opens the needle wider allowing the new gas to wash the piece out of the needle and seat.
Title: Re: CV issue
Post by: Burnout on April 06, 2020, 09:08:08 PM
I always put a droop in the fuel line to catch any sediment that gets past the petcock screen.
Title: Re: CV issue
Post by: thumper 823 on April 09, 2020, 07:54:16 AM
I am so far from stock I forget the simple things -
Yes the vacuum petcock should be thrown in in the trash as someday it will that day for you!
Title: Re: CV issue
Post by: Burnout on April 09, 2020, 09:29:24 AM
Sounds like it might be time for a float test. Those plastic foam floats sometimes absorb fuel.
Assuming you have a clean tank and a screen on your petcock and a new fuel hose.


I carefully place a suspect float on a concrete floor,
Then find something flat and very heavy and drop it on the float,
If it leaves a wet spot the float was bad......    :SM:

NOTE: You can stomp on it, but use hard sole shoes so no float parts can pierce your foot. (adding injury to insult)   :doh:

Replace float and "party on".   :soda:
Title: Re: CV issue
Post by: JBarrettB on April 09, 2020, 02:51:31 PM
Is the overflow tower split?

JB
Title: Re: CV issue
Post by: screem on April 11, 2020, 12:07:09 PM
Quote from: Diver625 on April 06, 2020, 06:31:34 PM
How old is the fuel line, the old ones decompose and pieces flake off of the inside and get stuck holding the needle open a bit. The first thing to do is shut the gas off and run the bowl out of gas. Then turn it back on and try it. When the bowl is out of gas the float drops down and opens the needle wider allowing the new gas to wash the piece out of the needle and seat.

I just had to replace a fuel line due to it flaking pieces of rubber from inside the fuel line. I had the float stick and puke fuel all over the shop floor
Title: Re: CV issue
Post by: cheech on April 11, 2020, 06:33:18 PM
Quote from: JBarrettB on April 09, 2020, 02:51:31 PM
Is the overflow tower split?

JB
Good call! Experienced this firsthand.