Ducati.org forum banner
1 - 20 of 28 Posts

·
Registered
Joined
·
139 Posts
Discussion Starter · #1 ·
2005 s2r 800

I had difficulty starting bike last night but started.

Started this morning, rode in to work. Was raining so i washed it at work.

After work bike does not start

In ON Position

Everything lights up
Kill switch is working
Bike is in neutral
Checked fuses all good
Bike turns over strong when i hit start but will not fire up

I DO NOT hear the fuel pump priming

Any help would be great in fixing this

I will tow the bike home tonight
 

·
Registered
Joined
·
1,318 Posts
The fuel pump is controlled by the engine management computer. When you hit the run switch, the computer powers a solenoid under the seat that sends power to the fuel pump and turns it on. The computer then checks the crank rotation sensor to see if the engine is running — if not, the computer cuts power to the solenoid after about five-seconds which then shuts off the pump.

First check if the pump works by running two wires from the battery to the in-line connector to the pump located under the tank. If the pump runs, then check that the solenoid is working. Listen for a click when you hit the run button. You should hear a second click off five seconds later.

If there’s no clicks, you likely have a bad solenoid. Replace it.

You should first check if the computer is sending 12 volts to the solenoid using a multimeter — if not, the problem is with the computer.

(The fuel pump supplies fuel under pressure as long as the crankshaft is turning, i.e., the pump is switched off by the ECU if the crankshaft stops turning as a safety feature to help avoid fires following an accident).
 

·
Registered
Joined
·
139 Posts
Discussion Starter · #4 ·
The fuel pump is controlled by the engine management computer. When you hit the run switch, the computer powers a solenoid under the seat that sends power to the fuel pump and turns it on. The computer then checks the crank rotation sensor to see if the engine is running — if not, the computer cuts power to the solenoid after about five-seconds which then shuts off the pump.



First check if the pump works by running two wires from the battery to the in-line connector to the pump located under the tank. If the pump runs, then check that the solenoid is working. Listen for a click when you hit the run button. You should hear a second click off five seconds later.



If there’s no clicks, you likely have a bad solenoid. Replace it.



You should first check if the computer is sending 12 volts to the solenoid using a multimeter — if not, the problem is with the computer.



(The fuel pump supplies fuel under pressure as long as the crankshaft is turning, i.e., the pump is switched off by the ECU if the crankshaft stops turning as a safety feature to help avoid fires following an accident).

Ok this is great stuff.. Thanks!

So check the solenoid is getting 12v first?

If so where is the solenoid?
 

·
Registered
Joined
·
139 Posts
Discussion Starter · #5 ·
Okay guys latest update..
Just came into garage, turned key to ON. the pump primed, the bike ran for 15 seconds (poorly) and turned off.

I them turned the key to ON twice and pump did not prime and bike did not start.
 

·
Registered
Joined
·
139 Posts
Discussion Starter · #7 ·
Okay here is a situation.
I am trying to probe the four cables going up to the fuel pump. (Red,black,white,black)

I cannot get my prong into either end they are rubber sealed in the wire coming out end, also as you can see in the picture the connecting end holes are tiny

Auto part Suspension Coil spring Engine Vehicle

Vehicle Auto part Car Steering wheel Automotive design
 

·
Registered
Joined
·
139 Posts
Discussion Starter · #8 ·
Ok another update.. If anyone is reading ;)

Managed to probe the power cables going up to the fuel tank

The white carries 11.5 v
The red carries 1.5v
The two blacks which i assume are ground carry none

Auto part Vehicle Engine Fuel line Automotive engine part
 

·
Registered
Joined
·
139 Posts
Discussion Starter · #9 ·
Update

When i hit the start button the red goes up to 10.9v

So should the red carry a a load with the key turned on like the white does? Or only when the start button is hit..

I am starting to guess that the problem is inside the gas tank, whether the actual pump or filter or?

Any thoughts
 

·
Registered
'12 848evo, '13 Hypermotard SP, '94 CBR600f2 track bike, '06 CBR600rr track bike
Joined
·
909 Posts
If you have trouble probing wire connectors try using safety wire or a small paper clip to get into the connector .
 

·
Registered
Joined
·
6,795 Posts
These voltages are not high enough.

Suspect battery condition, or resistance in the wiring loom.

Many threads on here recommending you replace your battery earth wire with a new one, going directly between the battery and the engine, if you don't already have one.

Also check charge rate with a voltmeter across the battery terminals when you get it running. Should remain above 12V, but not exceed 14.6 at revs.

The three yellow wires from the alternator meet the regulator/rectifier wiring behind the battery. This connector can give trouble at this age. It may be a bit 'crusty', or show signs of getting hot.

Good luck!

:)
 

·
Registered
Joined
·
6,795 Posts
Don't let this out! Lucas parts will not work on Ducatis. They have their own, Italian, version that's never been photographed! :stickpoke
Very good! :D

Those of us who grew up on British bikes know that Lucas parts don't work for long on anything.

Like my friend's old Thunderbird, which the lights used to go out on when he hit a bump. Not ideal mid-corner..

That's why they called Joe Lucas The Prince of Darkness!

:p
 

·
Registered
Joined
·
139 Posts
Discussion Starter · #15 ·
These voltages are not high enough.



Suspect battery condition, or resistance in the wiring loom.



Many threads on here recommending you replace your battery earth wire with a new one, going directly between the battery and the engine, if you don't already have one.



Also check charge rate with a voltmeter across the battery terminals when you get it running. Should remain above 12V, but not exceed 14.6 at revs.



The three yellow wires from the alternator meet the regulator/rectifier wiring behind the battery. This connector can give trouble at this age. It may be a bit 'crusty', or show signs of getting hot.



Good luck!



:)

Well i just emptied the tank and took out the unit. I will wire direct and see what it does. Will change the filter while here..

2 questions

1. You say those are not high enough volts. What should the voltage be ? Its 11v coming to the pump when i hit start. Is that not sufficient?

2. Now that i got this pump flange unit out.. What should i be looking for :)
 

·
Registered
Joined
·
139 Posts
Discussion Starter · #16 ·
Update..

I took the pump/flange assembly out and hard wired 12v from the battery to the back of the connector going into the pump.. The pump turned on, did it again just to make sure. And i heard her buzzing.. :) i guys the pump is good?

So now i have to go backwards and find where the break in the line is
 

·
Registered
Joined
·
139 Posts
Discussion Starter · #17 ·
Update

I have confirmed that the problem is a break in the 12v line somewhere between the out side of the flange and where it actually connects to the pump.

I figured this out by

Running 12v direct to pump and connecting the ground cable from the out side of the flange connection. Result pump runs

But

If i connect the ground direct to the back of the pump and run the 12 from outside the flange.. Pump does not run.

So now most of the 12v wire is inside a plastic casing.. How to find the break

Here is some pictures


This first one is the flange exterior which sits outside the tank and seals the gasoline. The red cable you see is the problem



This here is where it connects to the pump



And here is the whole you unit as it sits inside the gas tank. You can see most of the red wire is inside the black plastic part




"If i was educated, I'd be a damn fool"
 

·
Registered
Joined
·
139 Posts
Discussion Starter · #19 ·
UpdAte

If I wiggle the 12v wire the pump works no problem

I am tempted to just put it back but I know the first bump that I go over the loose connection will come off again

I just don't know how to get in there to secure the connection
 

·
Registered
Joined
·
139 Posts
Discussion Starter · #20 ·
As it stands now. I need to figure out how to get to wires and past the black plastic casing

What purpose does the black plastic casing serve there's all kinds of holes in it so the gas does go in there .. So then what function does it serve?
 
1 - 20 of 28 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top