Curious. I was under the impression that there is only one '09 model,
a 50 state model, with separator & charcoal canister. Apparently not.
I would think that the high temps would lessen the problem, if vent
line related, as internal pressure builds with the heat, more so, I
think, as the level drops. But if the engine vacuum isn't getting to
the diaphragm to hold it open, the pressure probably isn't enough to
overcome this. But then that raises the question as to why it will run
for a while, then die. Maybe as the vacuum tube warms, it softens and
allows the tubing to collapse. Might also be worth looking at the
possibility of a vacuum leak as the bike gets hot, rather than the
vacuum line collapsing. I think it was Big Cee that used to offer a
vacuum elimination kit for the petcock. Don't know if there is a
current equivalent.
Back to the possibility of a venting problem, did you have to blow
hard through the vent line to allow flow? You might try again with
very gentle pressure. In operation, there really isn't any appreciable
flow or pressure, just slight equalization to atmospheric pressure as
conditions change.
Anyway, either condition could be causing what would seem to be a fuel
starvation problem. It's now just a matter of determining which, or
what combination. Not to further confound the issue, but it seems to
me there may have been some discussion here a while back about a few
riders having vapor lock like symptoms under hot riding conditions.
Might be worth researching.
Dennis KD7CAC
On Aug 27, 2009, at 7:20 AM, mudokongrl wrote:
> Hi Dennis,
>
> i am guessing thats yours is a california model? i dont have any of
> that extra stuff you mention. i checked the vent line by placing a
> straw in the opening of the gas cap ring, that has a small o-ring.
> the nipple from the gas cap slots into it when its closed. from
> there, it goes to the back of the tank into a 90 degree fitting
> (thats part of the tank) into a line that goes straight down to the
> bottom of the bike.
>
> i have no blue/red markers, or seperator.
>
> i am in texas, and right now we are on our 66th straight day over
> 100 degrees, so its pretty hot out and about. ive read in a few
> places now that the vacuum line can collapse due to heat, so i am
> going to replace that and see where i end up.
>
> wrote:
>>
>> Hi Jason,
>>
>> It sounds to me like you checked the liquid (water) drain line, not
>> the vent line. The gas tank vent pathway starts at the hole in the
>> center of the bottom of the gas cap, which sees the tank interior. It
>> then passes through the cap and whatever is going on in there to
>> allow
>> one way air equalization, but not fuel passage (from sloshing). This
>> pathway then exits the gas cap through the nipple on the underside of
>> the cap, outside of the rubber tank sealing ring. When the cap is
>> closed, this nipple connects to a tube that passes through the tank
>> interior. This tube terminates under the cap with the small "O" ring
>> that can be seen in the well (depression around filler opening) in
>> the
>> top of the tank, same place the liquid drain opens (the one you put a
>> straw in?). The other end of this vent tube comes out the back of the
>> tank, under the front of the seat, along with a gas return line. The
>> vent line fitting has the blue marker, the gas return fitting has a
>> red marker. The rubber tube connected to this vent line fitting then
>> proceeds down the left middle of the frame, connecting to the
>> emission
>> system separator, that round black plastic thingy that you have to
>> move out of the way to get to your shock preload adjuster. This
>> pathway is where I would be looking for blockage. I would try gently
>> blowing down through this pathway (vacuum tube placed on "O" ring?)
>> with the tube disconnected from the separator. Use caution as there
>> could be raw fuel, or gasoline vapors, in this line!!! Don't suck or
>> have ignition sources nearby!!!
>>
>> If you find this pathway to pass air freely, then you might have a
>> bad
>> separator. A dealer should be able to test this device, if they
>> haven't already. I would reassemble the cap internals, as this could
>> be replaced under warranty, if found to be at fault, but not if it
>> shows signs of modification. Another area I would check is the vacuum
>> line that withdraws the diaphram in the fuel petcock. If something
>> isn't operating properly in that system, you might get enough gas
>> into
>> the carb bowl when the tank has more content, due to the force of
>> gravity and weight, but not enough as the fuel level drops. I know
>> you
>> said you checked this, but it might be worth double checking.
>> Unlikely, but a deficiency in the operation of both these systems
>> could be ganging up on you.
>>
>> I'd be curious to know what kinds of temperatures exist during these
>> adventures. I sometimes find my '09 wheezing after a ride on a warm
>> (hot) Phoenix day. Opening the cap stops this. This is partly why I
>> suspect the tank vent is one way, allowing a vacuum to be equalized,
>> but not pressure. Having gasoline vapors exiting the system could be
>> dangerous, among other considerations. In your case, opening the cap
>> is breaking the vacuum that may be the root cause of your problems.
>>
>> Hope this gets you on the right track.
>>
>> Dennis KD7CAC
>>
>> PS Switching to reserve when the problem occurs is only confirming
>> that the cause isn't solely a fuel level issue. However, if your fuel
>> level was nearing the switchover point, leaning the bike hard right
>> might break a vacuum in the tank by dropping the fuel level below the
>> main pickup, allowing the tank interior to equalize with the carb
>> bowl. Or maybe not - just a weird thought.
>>
>> On Aug 26, 2009, at 8:02 PM, Jason . wrote:
>>
>>> yes, stutters and jerks like its out of gas. however, switching to
>>> reserve while the bike is still running doesnt stop if from dying.
>>> once dead, if i am rolling down the road at 50 mph and switching to
>>> reserve it still wont start. doesnt seem to start until i open the
>>> gas cap.
>>>
>>> i checked tank venting by putting a straw to the opening in the gas
>>> cap ring, and blowing through it, while my wife held her hand over
>>> the bottom of the vent tube at the bottom of the bike, she felt
>>> plenty of air coming through. i have removed the vent seals within
>>> the gas cap in case they were sticking. i know all signs point to a
>>> venting issue, but it just isnt blocked anywhere.
>>>
>>> From: eagleeyedennis@...
>>> To: jason_555@...
>>> Subject: Re: [DSN_KLR650] little help needed
>>> Date: Wed, 26 Aug 2009 19:17:36 -0700
>>>
>>> Stutters & jerks like when it's time to switch to reserve?
>>>
>>> Do you have a service manual?
>>>
>>> How did you check the tank venting?
>>>
>>> Dennis KD7CAC
>>>
>>>
>>>
>>> On Aug 26, 2009, at 6:11 PM, mudokongrl wrote:
>>>
>>> hi folks,
>>>
>>> i have a 4 month old 2009 KLR with just over 4000 miles on it.
>