View Full Version : HELP: odd fuel issue


Slabrocks
March 23rd, 2010, 11:53 AM
The last few weeks it has been nice outside and i have been able to run 2 full tanks through the 01 with no problems. We have had 2 rainy days, not in a row, where the following day when i take the cover off the bike there is a very strong smell of gas.
The bike acts flooded and takes some work getting started. the last time it happened, the issue worked itself out and idled fine. today, i rode about 10 min and it was not able to idle for a stoplight.

does anyone have an idea where the smell would come from?

thanks for the thoughts

Oh yeah, I tried using the FAQ from "the other" site. I didnt see anything that helped.

Momaru
March 23rd, 2010, 12:08 PM
Any chance a fuel line is loose? Unlikely I know, but that's the first thing that pops to mind. Second is perhaps a bit of crud in your gas tank seal, keeping it from being airtight.

Slabrocks
March 23rd, 2010, 12:11 PM
as crazy as that sounds, i took some pics of my engine for another post and i physically touched the fuel lines (checking it out myself for the first time) and it was before i had issues. I really hope it will be that easy.

Momaru
March 23rd, 2010, 12:19 PM
Yeah. I had that funk for a little while when I added a larger in-line fuel filter. Found out a couple days later when I uncovered it that I didn't quite seal up the downspout tube. It had dripped a little and stank a lot.

Dunno what temperatures have been like the last few days in IN, but it might just be your tank venting hot air as it expands inside (our characteristic tank whine/whistle). If it is the tank seal, suppose your gas may've been fouled by the ethanol soaking up water out of the humid air (or just a bad batch o' gas).

Slabrocks
March 23rd, 2010, 12:24 PM
very humid air with not riding and keeping the bike covered during the rainy days. (outdoor parking)

about 55 day and 35 night for temps recently

Slabrocks
March 23rd, 2010, 12:53 PM
from bad to worse. rode back home from the coffee shop i was visiting and even with the choke on the bike wont idle. if im not holding the throttle open, i have a dead bike under me.

all the fuel lines are pushed up tight to where they are supposed to be. I have put over 400 miles on this bike already in the past 3 weeks.

hmmm help!!!

Snake
March 23rd, 2010, 05:05 PM
Have you checked your inline filter? Sounds like it may be clogged. The smell of gas may be coming from the normal venting of fumes that is being trapped by your cover and then released when you take it off.

Slabrocks
March 23rd, 2010, 05:10 PM
its the tiny internal filter. i havent messed with it yet, but for as cheap as the part is, i will probably change it this week.

think im better off with a big external one instead of the little white one?

Momaru
March 23rd, 2010, 05:18 PM
That's the general wisdom, but I can't recall any instances of the stock filter getting clogged. That said, haven't been looking for 'em

Slabrocks
March 23rd, 2010, 05:27 PM
i think it comes out cheaper. i think i read the internal one to be about 13 bucks

Slabrocks
March 27th, 2010, 03:22 PM
update: i pulled the fuel line off the carb today and there was something stuck in the fuel line. I pulled out my trusty "hook" tool, and had to really dig to get the obstruction out. It was that tiny little filter stuck deep in the line between the carb and the tank.

I put an external filter inline where the tiny one was, and im still having issues with the bike idling after i get it warm. It will stay running if I keep revving the bike, but even with the choke on over half, (should hold maybe 4k rpm at this spot) the bike dies.

any ideas? Thanks

Slabrocks
March 27th, 2010, 04:01 PM
I read on some other forum that i should try running it with the gas filler open to see if it may be a problem with the tank vent. that didnt work either.

kkim
March 27th, 2010, 04:14 PM
sounds to me like your pilot jets are clogged. try running a heavy concentration of seafoam directly into the carbs and let sit over night or pull the carbs and clean out the pilot jets by pulling them out and blowing compressed air through them.

Slabrocks
March 27th, 2010, 04:17 PM
i was hoping that wasnt going to be your answer. i have about 2-2.5 gallons of fuel in the tank. do you think i can just "overmix" seafoam in there and run the bike for say 30-40 min by riding it and see what happens?

I'd rather not take apart the carbs.

kkim
March 27th, 2010, 04:23 PM
I would take the fuel line off the petcock, find some way to funnel down/inject pure seafoam into the fuel line as you idle the bike. the seafoam will get pulled into the carbs and mix with the fuel in the bowls. turn bike off and hopefully that will be enough to clean/soften the crud as you let it sit overnight.

start it up the next day and pray the problem will be gone.

good luck... let us know how it turns out.

Slabrocks
March 27th, 2010, 04:25 PM
sounds too easy.
Im not sure if i will blame the filling station's gas for the issue, or me being able to take on 4.62 gallons at a fill-up and not knowing that i shouldnt ride the reserve that hard on a bike that i just started riding.

CZroe
March 28th, 2010, 09:52 PM
I gotta comment because this sounds WAY too similar to my "rainy night break-down" I had.

Slabrocks
March 28th, 2010, 10:52 PM
well, it seems you forgot to comment.

i got some seafoam today and since its raining, i figure id better wait until tomorrow to mess with it.

Slabrocks
March 29th, 2010, 04:11 PM
update: I figured out that there is gas in the oil. After a short search, i figured out that there is for sure a float or needle issue in the carb, and that i should be turning off the fuel petcock after riding.

At this point, I'm going to take off the carbs and see if i can get whatever is bad inside to go away.
Then, of course, im going to have the pleasure of changing the oil. I'm hoping to take care of it wednesday afternoon.

If anyone is still following this thread and has any advise about what to or not to do when pulling off the carbs, I'll be happy to take any advise.

kkim
March 29th, 2010, 04:47 PM
yes, a stuck float valve will allow fuel to flow from the tank to the carbs. usually the excess gas in the carb bowls exit though the overflow tube when this happens, but I have heard of instances of fuel flowing directly into the crankcase.

How did you figure out gas is in the oil? has the oil level been rising?

In any case, most times it's a piece of debris sticking the float valve open from the tank. Sometimes the debris can be dislodged by tapping the carb bowls with the plastic end of a screwdriver, if you're lucky.

check out the section on the float system...

http://faq.ninja250.org/wiki/How_a_carburetor_works:_Carbs_explained#PARTS_-_Is_Parts

Slabrocks
March 29th, 2010, 05:12 PM
Today I started the bike and it kicked right over with no issues. Since i have ridden quite a bit lately, i know what the engine was supposed to sound like. the valves sounded loud, so at the next stop i turned off the bike and checked the sight glass. it was completely full, and much thinner than usual.
I searched until i found 4 different places that all said the same thing.

Slabrocks
April 1st, 2010, 12:09 PM
last update unless someone has questions.
yesterday i prepared for an oil change and carb rebuild. in the evening i pulled the carbs and broke them down one at a time checking the jets and float for any dirt/rust that might have gotten to them. There was a spot on the jet that had turned white (meaning dry). I soaked the jets and floats in carb cleaner for about 5 min while wiping the parts down and then drying them with compressed air.

same with the other carb, but no white area on the jet.

completed a quick oil change to remove the gas/oil mixture from the crankcase

put everything back together and after getting fuel back into the carb, PRESTO!! it runs better than it ever has.
thanks for all the help