Puzzled.

[Limeyrider]

Hey 02GF74 .... thank you for your input.
I disconnected the flasher / starter inhibitor.
Connecting blue / white from the flasher / starter inhibitor to earth at the starter solenoid made the solenoid click, engine / starter motor remain static.
Connecting blue / white to blue / white and pressing the starter .... solenoid clicking ... no engine / starter motor motion.

 

[02GF74]

Can you confirm we are working to the same diagram, 1985-1989 US model.

This has starter relay with blue white wire, the other wires is red and goes to the battery, and black to the starter motor.

Also according to the manual the starter cut off relay and turn signal is one unit with 9 wires.

The post 1990 models have blue/white and red/white wires to the relay (red/black as above) . They have separate starter relay and turn signal, with 4 and 5 wires respectively.

Going back to your post.

Hearing the starter selonoid click is good. That is the sound of heavy duty contacts closing connecting the battery to the starter motor.... but I'm sure you knew that.

So why isn't the motor turning?

Possible causes:
- starter does not work
- problem with starter earth
- battery is not able to supply the current
- solenoid is faulty
- engine seized so starter cannot turn it but I'd have thought it would still make a sound

Sorry but more measuring.... Can you measure voltage on the output lead of the solenoid, red wire - this connects directly to the battery.
This should be at least 12 v
Then ground the blue/white and measure again, voltage should drop by a couple of Volts as the battery is being connected to the starter which draws a large current resulting in a battery voltage drop.

Do you know if the starter works?

The next test would be to connect a jump lead to battery positive and momentarily touch the output from the solenoid, this is shown as a black wire in the manual - in effect you are bypassing the solenoid. Be prepared to see a significant spark but it should bring the starter briefly to life.

 

[Limeyrider]

Can you confirm we are working to the same diagram, 1985-1989 US model.

This has starter relay with blue white wire, the other wires is red and goes to the battery, and black to the starter motor.

Also according to the manual the starter cut off relay and turn signal is one unit with 9 wires.

The post 1990 models have blue/white and red/white wires to the relay (red/black as above) . They have separate starter relay and turn signal, with 4 and 5 wires respectively.

Going back to your post.

Hearing the starter selonoid click is good. That is the sound of heavy duty contacts closing connecting the battery to the starter motor.... but I'm sure you knew that.

So why isn't the motor turning?

Possible causes:
- starter does not work
- problem with starter earth
- battery is not able to supply the current
- solenoid is faulty
- engine seized so starter cannot turn it but I'd have thought it would still make a sound

Sorry but more measuring.... Can you measure voltage on the output lead of the solenoid, red wire - this connects directly to the battery.
This should be at least 12 v
Then ground the blue/white and measure again, voltage should drop by a couple of Volts as the battery is being connected to the starter which draws a large current resulting in a battery voltage drop.

Do you know if the starter works?

The next test would be to connect a jump lead to battery positive and momentarily touch the output from the solenoid, this is shown as a black wire in the manual - in effect you are bypassing the solenoid. Be prepared to see a significant spark but it should bring the starter briefly to life.

Hey 2GF74 .... yes, we are working to the same diagram.
Starter cut off relay has nine wires.
The motor was turned over by the seller using a set of jumper cables ..... the original battery was defunct.
We have fitted a new battery of the same spec. as original.
As the starter motor turned the engine over at that point, we made some assumptions ... the engine is not seized, the starter motor was ok .... starter earth ok (?).

To be clear ... before I manage to fry the system ! .... you say "connect a jump lead to battery positive, and momentarily touch the output from the solenoid " is this black wire the earth, and starter cable connected to the negative terminal ? .
The only wires / cables coming from the solenoid are the red to battery +, and the blue / white wire.

Thank you for your time .... and patience .

 

[02GF74]

Hold off trying to jump lead the starter for now, since you saw the starter motor turn over so for now let's assume it is OK.

What have you done to it since that moment? You've replaced the battery yet you showed photo of 4 leads that were not connected - why was that?

Maybe worth charging the battery.

You can safely measure voltage on the starter solenoid terminals, before and after you ground the blue/white?

 

[Limeyrider]

Will do.
Work that has been done since getting the bike home .... rebuilt brake master cylinders, clutch master and slave cylinders ...obviously not electrical.
Yes, replaced the battery ... the four leads shown were not connected to anything when we began surveying the project.
The started solenoid has two terminals ....only one is connected .... red cable from the battery +ve ... is there anything that should be connected to the " spare " terminal ?.... e.g. a black -ve wire ??

 

[02GF74]

The only wires / cables coming from the solenoid are the red to battery +, and the blue / white wire.

No. A solenoid will have 4 terminals.

The two output ones are chunky copper threaded posts, (M10?) one of which is connected to the battery, the other post goes to the starter motor. See photo below.

You will notice the blue/white wire so what has happened to the 4th terminal I hear you ask? On early models this is connected to the red lead, but later ones have a separate wire.


WARNING!!!!! I've never worked on the Vmax starter circuit so am quoting from the manual and experience working on cars.

You best wait for one of our gurus to confirm that long black lead to the starter is indeed the power and not ground. (if its a ground then where is the power terminal on the starter???!!!)

So according to the manual, there is 1 lead to the starter motor (its common practice for the starter to be earthed via the engine), which is black, and that is consistent with the wiring diagram.

And starter motor black lead, that goes to the solenoid post. <--- HAVE THIS CONFIRMED





PS I don't see how the engine could have turned over if the output post on the solenoid is not connected to the starter motor.

 

[02GF74]

My money is on the fat black lead, that you were told to connect to the battery is the starter motor power lead that oughta go to the solenoid.

DON'T CONNECT IT WITHOUT FINDING OUT WHAT IS ON THE OTHER END,

 

[VMAXXIMUM]

You may want to remove the headlamp bulb as that is draining the battery when ignition is on, no harm leaving it I it just buys you more time as you investigate before needing to charge the battery.

+1 on disabling the headlight to preserve your battery during testing. However I wouldn't pull the bulb, I would pull the fuse. Seems easier.

 

[Limeyrider]

The blue / white wire is attached to a small terminal below the two " chunky " terminals. One of those larger terminal has the red cable from the battery attached ... the other larger terminal has nothing attached. The long black heavier cable, I have manually traced from the battery -ve terminal to the starter motor, the other black heavier cable is the engine earth apparently. So, the -ve battery terminal is occupied by two heavy cables . My VERY limited knowledge tells me that one of the solenoid terminals should have a black, heavy cable attached ??.
Your point about the engine turning over without having a connection from the solenoid to the starter motor only adds to the mystery ??? . I heard the engine turn over when the seller made connections .... I did not see how he connected the jumpers.

 

[Limeyrider]

This is the starter solenoid with present connections ....the lower, small terminal is the blue / white wire, the right hand terminal carries the battery feed, nothing connected to the left hand terminal.

 

[Limeyrider]

+1 on disabling the headlight to preserve your battery during testing. However I wouldn't pull the bulb, I would pull the fuse. Seems easier.

Thanks VMAXIMUM .... I did pull the fuse .

 

[MaxMidnight]

Hey MaxMidnight ... thank you for your reply ...and patience ...
Yes, the switch is ON, I have the " official " Yamaha manual with wiring diagram ( it is like showing a Chinaman the London underground map ! ).
Bridging the RED and BROWN wires I measured 11.4 volts.
There appears to be a problem with the flasher relay , there is a crackling sound at times ... and the starter relay stops clicking ???.
The ignition 10A fuse has two wires feeding it ... neither are brown, both wires are RED / WHITE, the Brown wires appear to be feeding the FAN fuse ??.

Not sure if a 1v drop across the switch is acceptable or not, either way I'd strip the switch and inspect the contacts.

The fuse block is fed by the brown wire from the ignition switch which provides power to all of the fuses. Ignition is red/ white, signal is brown, headlamp is red/ yellow and fan is brown.

I've attached a copy of the Haynes wiring diagram which I hope you will find more akin to a New Yorker looking at a NY underground map.

The condition of the blue/ white connector on the starter solenoid looks grotty and if the others on the bike are like that then that may well be the cause of the voltage drops you are getting.
To clean them up make and break the connector several times and make sure that the female part grabs the male...am I allowed to say that?
Do the same to all of the other connectors to ensure good contact.

If the black lead you connected to the -ve terminal comes from the engine ground then that is correct but you also need the long black wire shown in
Mr 0G2F74's starter picture to the starter solenoid.

 

[Limeyrider]

Hey Mr. MM, thank you for the attachment ... I will go over that carefully.
I think that the bike stood unused in a shed / barn for sometime, some of the electrical connectors are clean and relatively bright ... others not so much.
I need to clarify .... should the heavy cable from the starter motor attach to the starter solenoid on the stud that is next to the battery connection stud ? ... that would make sense to me .... but what do I know ! ?

 

[Limeyrider]

I wish that I had had the Haynes wiring diagram earlier ! .... so much easier to follow than the " official " Yamaha drawing.
Cleaning the connectors is simple enough ... and your comment is perfectly PC .
As you live in Cumbria.... you may know a village that has my surname ..... Satterthwaite ?.
Thanks for your input..... and patience !.

 

[MaxMidnight]

There are two large studs + the connector for the blue/ white wire.
One of the large studs is power in the other feed to the starter motor (the unoccupied stud in your picture.)
If memory serves well the starter cable goes through the grommet in the frame along side the red cables.

Satterthwaite is towards the south of the Lake District whereas we are just to the north of the county. Not a place I'm familiar with

 

[Limeyrider]

Hey Mr. MM .... I will be cleaning each set of connectors and checking connections ... found a couple of chafed wires ... bare conductor wire. The key to this whole issue was not properly following the wiring diagram ... the Haynes diagram is so much easier for a novice to read ... it is obvious now that the heavy cable from the starter motor should have been connected to the stud on the starter solenoid.
We visited the village several times when we lived in the UK ... not a long drive from Teesside ... and a most enjoyable destination. Thanks for your help.

 

[Limeyrider]

Success !! .... I cleaned as many connectors as I could find, cleaned and brightened earth connections.... attached the starter motor cable to the correct stud .... the engine turns over nicely now. Now to begin the ignition and carburation testing .... hopefully no issues. I stripped and cleaned the carbs. Thank you so much to MaxMidnight and to 02GF74 for their help and patience.

 

[MaxMidnight]

Good to hear you have got a result - long may they keep coming.

Suggest you run some carb cleaner through as well.

 

[Limeyrider]

Hey MaxMidnight .... I soaked the carbs, and fuel pump in a bath of carb cleaner for a couple of days, then blew them clean, sprayed cleaner through the carb jets .... hopefully that will have cleared any varnish et. Thanks again for your help.

 

[Fire-medic]

If you didn't remove the jet blocks, and then the brass jets inside, and physically inspect them, and poke 'em clean, if they were unable to be seen-through, chances are the pilot jets are still blocked, if they were in the first place.

Sometimes they won't easily come-out, use a left-handed drill for removing those.