HELP!

I got the bike dyno tuned late last week. When I got her home, I started taking her apart for some maintenance before a two week ride at the end of this week. I drained and flushed the coolant, and then filled with new coolant. Then I drained the oil, replaced the filter and refilled with oil. I also removed, cleaned and oiled the BMC filter.

Per the service manual procedure, I ran the engine with the radiator cap off, to let bubbles escape, turned her off and topped up the coolant. Then I was going to let her run until the fan came on, and finish the procedure by topping up the coolant reservoir. But as soon as she started, the motor stumbled and died, just like she was running out of fuel. Sure enough, fuel was very, very low. So I added a gallon of fuel or so and she simply will not start.

If I spray a touch of starting fluid into the fairing grille, she starts, revs and dies. So, ignition is working. That would seem to rule out the bike down sensor, kick stand sensor, etc.

The LEDs on the Power Commander track the throttle, if I open it, while cranking. It also tracks the idle adjustment if I adjust it while cranking.

I can hear the fuel pump run when the ignition is turned on. When I disconnect the fuel supply line, a few drops of fuel escape as would be expected. So, fuel is getting that far.

I've charged the battery in case starting voltage was getting low. That didn't help.

It seems like the motor just isn't getting fuel. I guess I should check the fuel supply hose on the motor end to make sure it isn't kinked. Short of that I'm stumped. Maybe I need to prime the fuel pump some how. I guess I assumed it would be self-priming, but I've never run the fuel dry before, so I just don't know.

Any suggestions?

-Matt

* Last updated by: MattTheHat on 6/22/2009 @ 5:31 PM *

When I disconnected my fuel line from the pump to replace the tank,I got quite a bit more than "a few drops".How's your idle adjustment?Maybe inadvertently got turned down somehow?You're not holding the throttle closed on startup are you?That will kill the engine(in my experience).Pump should be self priming-I believe that's what it's doing when it comes on like that.You could set your LCD menu to "voltage" and see what it's reading at startup and running.

* Last updated by: blue07 on 6/22/2009 @ 1:22 PM *

Thanks for your input, Blue.

I've got the battery charged hooked up while I'm starting. After leaving it for a few minutes, the bike indicates 12.8 volts. That drops while cranking to 11.9 volts. That seems a bit low to me. It's the original battery, so I guess it could be starting to die a slow death.

I've adjusted the idle up and down trying to find a place where it wants to start. I'm not holding the throttle shut, and I've got the idle adjust a bit high, just in case.

I'm starting to suspect the fuel pump or filter or something. I guess I could manually key the fuel pump relay and see if fuel squirts out the supply fitting.

-Matt

Ya-maybe-it does sound like a kinked hose-how about the small return line(could that be plugged or pinched somehow creating a vacuum in your tank?).(don't know if that would starve the pump of fuel)If it's starting,it's getting SOME fuel.

* Last updated by: blue07 on 6/22/2009 @ 1:56 PM *

Well, it's not starting at all. I mean, if I shoot a dab of starting fluid in the intake it will fire up until it burns off, but then it immediately dies.

I checked both the main line and the vent line and both appear okay. In fact, I went ahead and disconnected the vent line for now.

After being on the charger for a bit longer, the bike is now reading the battery voltage at 13.0 volts. I'm sure after cranking for a few seconds it would start to drop, but it seems to be acting normally to me.

I guess my next step is to check the fuel filter to make sure it didn't somehow get clogged. Then I'll be trying to key the fuel pump relay to see if it spits fuel. Got a feeling I'll be spending the afternoon with the service manual.

-Matt

* Last updated by: MattTheHat on 6/22/2009 @ 2:52 PM *

Interesting. The battery voltage is now up to 14.2 volts. And she started right up. Then died. Started her right back up and then died.

I'm wondering if the PC III is shutting the ignition down for one reason or the other. The bike isn't throwing any trouble codes. Not sure if the PC III keeps it's own set of trouble codes or not.

-Matt

I'm getting somewhere now. I noticed that the LEDs on the PowerCommander don't stay on after the initial power on sequence. However, if I hook up the external 9VDC battery, they do stay on. Suspecting the PCIII, I took it out of line and replugged in the factory ECU harness into itself (ie stock). The bike fires right up and seems to run fine.

I recall the ground connection being really sensitive from some older threads. I guess I need to double check that, and then see if that doesn't help.

-Matt

SON OF A BE-OTCH!

It was the friggin' ground wire. Moved it to the water bottle and it works fine. While I had it all apart, I had also removed the frame sliders and reinstalled the motor mount using red Loctite. My PowerCommander ground was run from the support bar from the left motor mount to the frame, just under the tank. How it worked before I have no idea.

I hope someone can learn from my stupidity. Nothing like wasting almost a whole day. Especially when I'm supposed to hit the road in a couple of days.

GEEZE!

-Matt

* Last updated by: MattTheHat on 6/22/2009 @ 5:31 PM *

I had almost the same problem a couple of days ago. Picked up a leak in the radiator. She got very hot before I shut her down. The plastic where the top mounting bold went through the water bottle started to melt. That's where the PC ground wire was. She wouldn't start. I pulled the ground wire out of the disfigured plastic and moved it down to the bottom mounting bold. Fired right up and got me all the way home. -bg

If someone has a starting issue the first thing I ask them is "Do you have a PC"? If yes thats where I tell them to start. Check the ground.

Well, I vaguely recalled all sorts of nightmarish tales of the dreaded PC ground. If it wouldn't have been for that, I'd probably still be wrenching on her.

I guess it's also good to remember that even if the PC were to completely fail, bypassing it is pretty darned easy. At least once you get the fairing off.

-Matt

I had no idea you had a PC on there(I didn't even THINK of that-sorry).Glad ya got er fixed-with a minimum of headache!Ride safe!

Moved it to the water bottle and it works fine.

This may crop up again. On my bike I installed a lock washer against the motor and flat washer against the bottle with loctite (When it gets hot the bottle gets soft & ground becomes crap). The battery - is still probably your best trouble free location.

Thanks, Romans. I seemed to recall that wasn't the best place to mount it, either. Either the battery itself, or the ground distribution lug on the right side of the frame (right in front of the battery cover) would probably be a good candidate, though I think I would have to extend the ground wire to reach either.

I'll leave it like it is, seeing I'm heading out to ride a several thousand miles over the next ten days or so. With any luck I'll get to move the ground again, only this time on the side of the road somewhere. :)

-Matt