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2002 v11 Scura electrical issues....need help


plexiform

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so i went with a Yuasa AGM

 

I checked behind the helmet lock and did nnot see any wires attached to the frame so not sure where the ground is going.  Anyone able to explain or show a picture of what the wires on the battery leads should look like?  Thanks

 

I will look at the ignition switch in the meantime.

 

I have a trouble-free Yuasa in my Scura - and no modifications to wiring, with the exception of an extra ground to the voltage regulator case.

 

For the ground, look behind the seat lock, not the helmet lock.  Remove the seat lock (2 allen screws). The ground should be securely attached to the transmission case behind the seat lock.

 

Some have cured the melting fuse problem with a MAXI fuse holder instead of the OEM 30-amp in the fuse block. Docc has some good posts on the issue. I put one in my LeMans as a preventative measure, but didn't get around to putting one in the Scura yet.

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Ground is in place behind seat lock as described above. I get 12.8v across the battery and across the positive lead and anywhere on the frame so I am assuming that means ground is doing what it's supposed to. Is that a correct assumption...? Haven't delved in to the ignition switch yet but that will be next. If there are any other thoughts I'm all ears.

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Does the fuel pump run for a couple of seconds each time you cycle the ignition or kill switch? It might be hard to hear but it should also start and run while the engine is cranking (I'm thinking is the timing sensor ok, fuel pump ok)

 

Check for spark at each plug

 

Measure the resistance from each plug cap to chassis.

 

Anyone know an easy way to measure the fuel pressure? (about 45psi I think, that would also confirm the pumps running)

Make sure you have a good pair of relays in position 4 & 5

 

Measure the TPS mV, it should be in the 400 - 500 range, rise steadily to about 4-1/2 Volts with throttle opening.

 

With the bike cranking over measure the Voltage at the switched fuses, I'm wondering if there's excessive Volts dropped somewhere like thru the switch, starving the ECU

On that note is the ECU connected to battery negative?

 

 

 

Don't despair Plexiform she is just testing to see if you are worthy  :grin:

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Heres a typical VII

http://www.thisoldtractor.com/guzzi007/schematics/2004_V11_Sport_Catalytic.gif

 

Note you can measure the ECU Voltage (Negative) from pin 2 of the connector item (43) to fuse 1, should be ~12 Volts

 

Wrap a small wire around pin 87 of relay (46) and monitor the Voltage to chassis. When you turn the key On you should see it go +12 for a couple of seconds and hear the pump priming then it will go to zero.

When you press start and the motor turns over it should go +12 again letting you know the pump, coils and injectors are getting powered up.

(The little sensor in the timing case picks up pulses telling the ECU when to fire etc)

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Does the fuel pump run for a couple of seconds each time you cycle the ignition or kill switch? It might be hard to hear but it should also start and run while the engine is cranking (I'm thinking is the timing sensor ok, fuel pump ok)

 

Check for spark at each plug

 

Measure the resistance from each plug cap to chassis.

 

Anyone know an easy way to measure the fuel pressure? (about 45psi I think, that would also confirm the pumps running)

 

Make sure you have a good pair of relays in position 4 & 5

 

Measure the TPS mV, it should be in the 400 - 500 range, rise steadily to about 4-1/2 Volts with throttle opening.

 

With the bike cranking over measure the Voltage at the switched fuses, I'm wondering if there's excessive Volts dropped somewhere like thru the switch, starving the ECU

On that note is the ECU connected to battery negative?

 

 

 

Don't despair Plexiform she is just testing to see if you are worthy :grin:

-----------

1. Despair is definitely setting in

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Does the starter turn over before the fuse blows?

 

I'll have to try again in a little bit but i think it does turn but then the fuse blows pretty quick and i dont get a good chance to here it.  

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Despair: I just recovered from my own self-inflicted oil-leak despair. You'll get there too. Looks like the stable-mates will keep you riding while you sort this out.

 

History: Did you ride the bike before you got it? By that I mean: did it appear to be trouble-free and then this problem just suddenly appeared - or is it possible that this is the reason the PO sold the bike?

 

Color: Scuras are supposed to be dark and stealthy. I think yours suffered deep psychological trauma by being gussied up like a cheerful Coppa Italia. It's like making an introvert dress in pastel florals and go to a baby shower. Simply dreadful... It's acting out against social pressures that go against its nature.

 

Relays: I have seen more than one problem solved by replacing all 5 relays with 5-pin Omrons. It's an inexpensive, and easy thing to do. It also gives peace of mind against future relay failure.  Get 5 of these:  http://www.digikey.com/product-search/en?x=-987&y=-73&lang=en&site=us&KeyWords=z2247-ND

 

 

 

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So the starter does turn and the engine is turning but then it all starts to slow down pretty quickly.  And if I keep pressing the start button for more than a few seconds then it will blow the fuse.  I stopped before the fuse blew this time. 

 

 

Yes I think youre right about the psychological insult due to the paint job.  It looks pretty nice in person but this Scura is definitely acting out big time!

 

I'll order those relays.

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Could it be this simple???

 

I just noticed the 8th fuse spot was empty.   But the fuse box cover says it should have a 15a fuse in it.  I placed a new 15 fuse in it and this time the bike started.   What is that fuse for?  I only let the bike run for a few moments and shut it off because its not even 7am and my neighbors would not appreciate the revving.  Will wait an hour and start it again and go for a ride.

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Ok the fuse blowing as soon as you press start is new info. Looking at the starter solenoid you will see a spade connector, pull it off and the fuse should not blow, you will hear the relay click each time you press start.
Check the main connection at the solenoid. If the main +12 is missing or the solenoid contacts don't close it will draw 45 Amps continuously, the fuse will blow in about 1/2 second.
 

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Oh you got it started now, things are moving too fast to follow. You couldn't get it to crank a moment ago.
Do you have a silver thing hanging below tank with hoses, that's the electric petcock, lots of owners remove it so don't need the fuse, I wouldn't.

The fuel pump can suck past a closed electric petcock but it struggles a bit, you can hear it moaning.

 

Now you have her going she will reward you big time.
 

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Yup that was it! Electric petcock and for some reason previous owner did not have a fuse installed for it. I guess the one time I started it when I went to pick it up there was already enough fuel in the lines but by the time I tried it at home it needed more fuel out of the tank which did not happen because the peacock was not functioning. Thanks for your help!

 

Took it out for a ride and it sounded good. Suspension needs some tweaking. Feels a little too stiff in the steering damping which makes it feel awkward.

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That's great, you sorted out why the fuse was blowing then?

 

If you look at the petcock two black wires come from the bottom, right where they come out of the epoxy is a common break point so ty-wrap the wires to the body to take all the strain.

Strange the PO should remove the fuse without changing the valve, some owners pull them apart and snip off the valve, easy to check just disconnect the hose if fuel gushes out it's been circumcised otherwise it will only run out with the key On

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