Yet another click no start problem, but with no click !! - 2001 Rosso Mandello

[William851]

All

I am sorry to start a new thread about what seems to be an old problem but I am getting an issue with my Rosso Mandello - after an evening of investigation  the problem seems to be that the starter circuit works fine,  I am getting 12.7 ish volts at the spade terminal when pressing the start button but when I connect it to the solenoid the voltage disappears and I do not get the solenoid click or starter motor engaging!!!

When I press the starter I get the fuel pump prime and the relay clicks.

I have bypassed the ignition switch and the problem remains.

I have checked the starter motor off the bike and it works fine.

if I run a wire directly to the solenoid spade from the battery, I can get it to engage the solenoid and spin the starter motor.

I am going to try and run with an auxiliary direct supply in the short term but would really like the bike to work the way Guzzi designed it !!

Any guidance would be gratefully accepted.

 

 

 

 

 

 

[luhbo]

When I have such problems on my bike, what happens every 5 years or so, it's usually a bad ground, caused by either worn or greasy brushes. Remove the metal cap at the back of the starter and check the length of the brushes. You will also see whether the mags are broken or not. If they are broken you'll see a lot of small magnet particles/pieces between and around the brushes.

Hold the starter button, ask your friend to pull in the clutch, then give the metal cap a slight knock (while it's still on the starter), using a 12/13 spanner or the like. Should the starter engage the moment you kick it you can be sure it's the above mentioned ground problem.
 

[William851]

All

After all that it was a dodgy starter relay !!

 

William

 

[LowRyter]

reseat the neutral cut out switch on the left side of the gearbox.

[docc]

Best Relay The position #1 5-blade relay is a good place for a bona fide High Current Relay. But recommended for all five positions... on a Rosso Mandello, especially #2 (and #5).

[Kiwi_Roy]

On 6/12/2019 at 1:04 PM, William851 said:

 

 

 

[docc]

I was pretty sure the 2001 Rosso Mandello still  has the early start wiring through the front two relays.  William851, take the "Livin' Easy Test" for your Relay#1.

And score those High Current OMRON for a full house of Best Relays.

[Kiwi_Roy]

I missed that its a 2001, easy thing to do is plug a test lamp in the relay socket /30, see if its alive with the key off

 

Revised June 26 2019

All

I am sorry to start a new thread about what seems to be an old problem but I am getting an issue with my Rosso Mandello - after an evening of investigation  the problem seems to be that the starter circuit works fine,  I am getting 12.7 ish volts at the spade terminal when pressing the start button but when I connect it to the solenoid the voltage disappears and I do not get the solenoid click or starter motor engaging!!!

No, its not fine, this is classic Startus Interruptus.

 The Voltage you measure at the wire (unplugged) is without any load, it will seem normal even though there could be significant resistance in the circuit. When you plug in the spade connector there is a heavy load connected so the Voltage drop due to resistance between the battery and the spade shows up. You cannot afford even a fraction of an Ohm anywhere in this circuit. It may be as simple as a bad relay or loose connector at the relay socket.

I found this sketch I did for someone showing the effect of resistance, in this case about 0.2 Ohms between battery + and spade connector.

The resistance has caused the Voltage  at the spade connector to drop in half, this drops the current through the coils in half so the strength of the solenoid is also half what it's supposed to be so all you would hear is the click of the relay or perhaps it might crank intermittently. If the solenoid manages to close the main contact the starter will crank at normal strength.

Note: I only show resistance at a few of the possible points

 

[docc]

1 hour ago, Kiwi_Roy said:

I missed that its a 2001, easy thing to do is plug a test lamp in the relay socket /30, see if its alive with the key off

Ah. So, on earlier wiring that relies on the relay, the outboard spade connector is hot and on later V11, that connector is switched through the ignition switch?

[William851]

All thanks for your replies, I have been away and have not been ignoring you !! Bike seems to be running fine now !