Kawasaki Ninja ZX Forum banner

1061 - 1080 of 1081 Posts

·
Registered
Joined
·
1,781 Posts
J- glad you got that 1 last ride in.

I just saw -5 this AM on the way to work-burrrrrrrrrrrrrr
 

·
Premium Member
Joined
·
3,675 Posts
Wow, what story with 9R will have. Congrats
 

·
Registered
Joined
·
3,884 Posts
Discussion Starter · #1,068 ·
So, I was having starting issues yesterday.
If I hit the starter button I just get a click.
Checked battery, starter motor, electrical connections and starter solenoid; all confirmed good.
Turns out if I unplug the fuel pump or fuel pump relay the bike starts no problem.
Ok. unplug the fuel pump, start the bike, plug pump back in and go for a ride.
0 issues at all.
Even restarts without issue.
What is happening?
I rode about 120-150 miles yesterday over a 2 hour period and had absolutely zero issues.
I was reading around that this is a common thing on the zx7 so hoping somebody can chime in and help me out?
 

·
Registered
Joined
·
298 Posts
When you press the starter button, a feed also goes to the fuel pump power relay, through a diode, and then back out to the fuel pump. Once the start button is released, its a pulse from the ECU to the number one coil that also goes to the fuel pump power relay, to tell it to provide some power to the fuel pump for a short time. This is so the fuel pump is not constantly working.

So chances are you either have a fuel pump problem, or a fuel pump power relay problem. Change which ever is convenient, or open the fuel pump up, and see if you can see a problem in there, sometimes the contacts in the pump can get worn or welded together. I'd check the pump as the power relay is a sealed unit.
 

·
Registered
Joined
·
3,884 Posts
Discussion Starter · #1,070 ·
When you press the starter button, a feed also goes to the fuel pump power relay, through a diode, and then back out to the fuel pump. Once the start button is released, its a pulse from the ECU to the number one coil that also goes to the fuel pump power relay, to tell it to provide some power to the fuel pump for a short time. This is so the fuel pump is not constantly working.

So chances are you either have a fuel pump problem, or a fuel pump power relay problem. Change which ever is convenient, or open the fuel pump up, and see if you can see a problem in there, sometimes the contacts in the pump can get worn or welded together. I'd check the pump as the power relay is a sealed unit.
Thanks
I have a spare pump relay and that didn’t change the symptoms.
Going to tinker tomorrow after work and see what’s up.
 

·
Registered
Joined
·
3,884 Posts
Discussion Starter · #1,071 ·
I opened the top of the fuel pump and everything looked in good shape. Not sure if that means anything though.
 

·
Registered
Joined
·
298 Posts
If I remember right there is a set of make brake contacts in there a bit like old car ignition contacts, sometimes these weld together or ware out, it could also be the fuel pressure diaphragm part of it.

For it to work it needs to sense the fuel pressure is down in the fuel pipe lines and have power to the pump before it will try to pump. I think fuel pressure is around 3 or 4 psi.
 

·
Registered
Joined
·
3,884 Posts
Discussion Starter · #1,073 ·
Tried known good pump and same results
Get a dribble of fuel from out line to carbs
Possible fuse box going bad can cause this?
 

·
Registered
Joined
·
3,884 Posts
Discussion Starter · #1,074 ·
So
Bike starts running on less than 4 culinders about 20 miles into a ride
Can’t find anything obviously wrong anywhere
Any ideas?
 

·
Registered
Joined
·
298 Posts
Rest a finger on the end of the fuel pump while pressing the start button, then again while the engine is running.

While pressing the start button, I would expect you to feel it constantly knocking as it pumps, then when the engine is running, it should slow to a knock every second or so.
 

·
Registered
Joined
·
3,884 Posts
Discussion Starter · #1,076 ·
Swapped fuse box and still won’t statt with pump or relay connected.
If I bypass the pump and gravity feed the carbs it runs great. Rode for over an hour at varying speeds and engine loads with 0 issues. So for now that’s what’s happening.
Any ideas?
My next thought is a new wire harness
 

·
Registered
Joined
·
298 Posts
I would imagine your losing the feed from the coil to the fuel pump power relay. This could be a bad ECU or coil. But check the cheaper wire option first.
 

·
Registered
Joined
·
3,884 Posts
Discussion Starter · #1,078 ·
I would imagine your losing the feed from the coil to the fuel pump power relay. This could be a bad ECU or coil. But check the cheaper wire option first.
I have a spare set of coils and ecu
I’ll try that out next time it’s apart
So far so good running straight from the tank though
Just rolled over 1000 miles and completed the break-in procedure
She runs real well but suspension needs work this winter; service and tuning
 

·
Registered
Joined
·
3,884 Posts
Discussion Starter · #1,079 ·
So I’m nearimg the 2000 mike mark on my current set up. In process of replacing sprocket carrier bearing and rear tire. One thing I’ve noticed is I think I’m running out of fuel at high speed. I’m still running gravity feed from fuel tank without a fuel filter and it’s great so far.
I’d like to put the pump back in but it’s like why ruin a good thing?
Also I’ve noticed that I can leave my battery plugged in without it dying unlike before when I would have to unplug negative cable or battery would die regardless of age or temperature.
I’m guessing there is some correlation between the two happenings....
 

·
Registered
Joined
·
3,884 Posts
Discussion Starter · #1,080 ·
Just had the wheels powder coated and new tires and wheel bearings. Suspension is off for service/revalve/tuning. New 520 chain and sprockets as well. I think i'm nearing 40k with this one.
 
1061 - 1080 of 1081 Posts
Top