carb question....

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After it dies leave the ignition switch on and check for spark, fuel flow and maybe power going in and out of the switches? Sounds like something electrical and Im not good at that part. Good luck man.
 
I took both the fuel tank breather hose and fuel pump hose )between the pump and filter and blew air through them......hopefully anything in there is gone.....the breather one did act like it didnt wanna accept the air....like it was blocked.
Tell me.....I have a glass filter so I can see the gas flowing....how fast should the fuel flow when you rev it?
Doesnt seem like it flows much different compared to idle.

You can make it a mile or so on the fuel already in the bowls.You won't see it flowing in the filter by reving it.
 
I had problems with fuel pressure and could hear the pump constantly working each time I turned the key on and for a long while during 1st minutes of idle. I found the tiny rubber valve inside the fuel pump had somehow fallen out of the hole it is supposed to be mounted in. That left only the little rubber valve on the output side of the pump to do all the work. After reinstalling that rubber valve into the proper position on the inlet side of the pump, my max acted normal again.

You should hear the pump clicking momentarily upon first key turn. Then only occasionally hear a click while idling. It isn't too big a task to remove the pump and check those inlet and outlet rubber valves. Just pay attention to how the pump is assembled, etc... so that it goes back with the ends aimed the same as they came off - for directional 'functionality' of the inlet/outlet nipples.

It sounds like maybe, just maybe your pump could be out of whack on both inlet and outlet end at the same time and not building enough pressure to provide adequate fuel under riding conditions.

Anyway, it's an easy inspection to do and maybe fixable for free.

Good luck. :hmmm:
 
ok....heres the results from blowing the air through both lines....
today is day 1:
drove to work this morning....15 miles 1 way.....ran great!
left work at 4pm (Wholly ****....HOT outside!) 15 miles back home....ran great!
hmmmm.....hopefully it wont rain tomorrow so I can see if tomorrow is the same as today!
I THINK I found the problem....hopefully....lol
Randy
 
Dreamster66, my new (used '99 but new to me) is doing the same thing. It will run great for miles sometimes then want to die. Any luck with the clearing the vent lines? Is your problem still gone? Which is the tank breather line? I see a clear one that goes to the coolant. A smaller black one right next to it that I think goes to the batter. Then one in the back by the shaft that just drains the gas overflow area. But where is the fuel tank breather?
 
my problem ended up being the thermo ground wire (the wire thats fastened to the top of the filler neck)
When it got warmed up, the thermo unit couldn't work properly cause the ground wire was almost broken ALL the way off....stripped the wire back and put a new crimp on it and re fastened it.
Make sure you are vapor locking too.
 
my problem ended up being the thermo ground wire (the wire thats fastened to the top of the filler neck)
When it got warmed up, the thermo unit couldn't work properly cause the ground wire was almost broken ALL the way off....stripped the wire back and put a new crimp on it and re fastened it.
Make sure you are vapor locking too.


That was greek to me, what is a thermo unit and where is it? what is a filler neck and where is it?
I hope I'm not the only one in the dark here...

Steve
 
Steve, remove your right scoop. It's the left electrical plug. The bigger one is the fan switch and the smaller is the thermo unit which operates the temperature gauge. On top of the coolant manifold you'll see a black ground wire fastened there.....that's the wire Randy is referring too.

Mark
#1098
 
Thanks for clearing that up for me! I had the right scoop off when changed the coolant to Engine Ice and didn't notice a ground wire. I'll have to look better next time I have that scoop off.

Steve
 
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