F3 running problem... any thoughts?

redcliffs · 01-30-2004, 3:55 AM

ok... so when my g/f Tanya was riding her 96 F3 home from work today, the bike started failing and then coming back, as though it weren't getting enough fuel. She checked the tank -- plenty of fuel. Turned to reserve -- helped for a second, but then not. Stalled a couple of times. Got home, after lunch was able to start the bike only with great difficulty, continued to have problems for a block, then turned around and drove the car instead.

Where do we start? What could it be? Possibilities we've though of (without knowing the relative probability of any of them) include: fuel pump either dying or having a lose connection; fuel filter; air filter. Could there be a problem in the petcock system? What could it be to have come on so suddenly? Would water in the fuel do this?

thanks!

G-Force Junkie · 01-30-2004, 4:37 AM

I'm thinking fuel filter clogged? Bad tank of gas? Water in the gas? Loose or corroded electrical connection?

BDA116 · 01-30-2004, 11:10 AM

The F3 will run fine at slow speeds with smooth throttle inputs if the fuel pump goes out. It will start bucking like mad at higher speeds or quick throttle inputs.
I've had that happen.
If it is running like this at all times, I'd suspect bad gas and/or a bad fuel filter.
Checking the petcock is easy - just pull the hose off and turn it to 'on'. If gas flows, the petcock is fine.
Drain the tank, replace the fuel filter and fill 'er back up with a fresh tank of gas.
See what happens after that.

Trouble · 02-03-2004, 12:13 PM

I assume the petcock on the F3 is identical to the one on my F2. There are two hoses off the petcock. The big one (pointed straight down) that delivers fuel and a smaller one (pointed toward the front of the bike) that is a vacuum line to the engine. The F2 petcock will not deliver fuel without a vacuum on the front line.

dB · 02-03-2004, 12:27 PM

My first thought was an obstructed tank vent. Does it audibly suck air when you open the filler?

bubba · 02-08-2004, 11:35 AM

have you figured it out yet?

redcliffs · 02-08-2004, 8:08 PM

Quote:

Originally Posted by bubba

have you figured it out yet?

yes and no -- the problem went away, but we have no idea why. When my g/f went out to fix it last weekend, the bike started right up and ran smoothly. No problems commuting all last week.

the latest theory, therefore, was that there was some condensation during the cold nights recently, this condensation sank to the bottom, so for a brief time there was water running through the fuel lines...

bubba · 02-08-2004, 10:09 PM

Quote:

Originally Posted by redcliffs

yes and no -- the problem went away, but we have no idea why. When my g/f went out to fix it last weekend, the bike started right up and ran smoothly. No problems commuting all last week.

the latest theory, therefore, was that there was some condensation during the cold nights recently, this condensation sank to the bottom, so for a brief time there was water running through the fuel lines...

when she commuted did she hit any high revs on the bike (over 8k)? did you see the problem before at high or low revs?