1200cc 2 stroke electrics help

1200cc 2 stroke electrics help

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TheHighlander

Original Poster:

1,329 posts

205 months

Monday 10th June
quotequote all
I’m only posting here as it’s a 2 stroke.

I have a Yamaha XLT1200 2002

I got ripped off buying it but that’s another story.

Engine has melted 3mins into use.

I’ve fully rebuilt it but now it’s dead, no power.

It doesn’t have a immobiliser or security code

The starter solenoid burnt out when it melted itself.

So this is what I’ve done

To eliminate the clocks I ran power to them direct and they fire up.

New battery
New battery solenoid
Earths are good
All connections seem good with no corrosion
One stripped the kill switch and starter switch and they look ok, I have bought a new one today for £80 just incase.

I get power from the battery to one side of the solenoid as it’s a direct feed

If I cross the solenoid it cranks over but no spark.

I’m not great with electrics but not sure where to go now.

The other option I have is to purchase a complete loom with CDi which is £350 but ideally I don’t want to do that after paying for the rebuild.

Any assistance would be great.

I did try the old battery and solenoid to check but nope.


OutInTheShed

9,368 posts

33 months

Monday 10th June
quotequote all
To make the starter motor crank, it just needs 12V? It' s like a bike starter motor, a dumb motor with a one-way clutch, not a pre-engage starter like a (modern-ish) car?
The starter should spin if you take a jump lead from the battery + to the motor terminal?

Ignition is more complicated. I don't know the particular motor, I imagine you will have a coil for each plug, a stator coil whiich provides power, and a trigger coil which tells the electronics when to fire?
Or the power may come from a battery circuit.
Can you post a wiring diagram?

It helps to be clear, is it dong nothing at all, cranking buit not firing or what?

If it's like the outboards I deal with, the 'kill switch' will 'kill' the ignition, and inhibit the starter motor,
Also there may be interlocks like it must be in neutral to crank for example.
Some outboards will crank but not fire if the kill cord is pulled, I guess jetskis might be the same?

TheHighlander

Original Poster:

1,329 posts

205 months

Monday 10th June
quotequote all
Thanks for the response.

So it cranks if I cross the coil, cranks freely.

If it had a immobiliser you would think it had locked itself down.

It’s dead with no power.

Correct there is 3 separate coils

This is the main electrical box

CDi unit
3 coils
Starter solenoid


Steve Bass

10,364 posts

240 months

Monday 10th June
quotequote all
Jumping the starter solenoid won't activate the ignition circuit. All you're doing is sending voltage to the starter motor which is spinning over the motor over.

Do you have a wiring diagram you can share?

And this is a snow mobile?/Waverunner?? 3 x ignition coils and 3x carbs or fuel injection?

And as a first step, have you checked compression in each cylinder??
If yes and they're good...... lets start with the ignition side of the equation.... when you turn the ignition on, you should get a steady positive voltage on one side of each coil. The coils should be fired by a switched negative.
if not, check if one side of the coils are a direct short to the chassis ground.




TheHighlander

Original Poster:

1,329 posts

205 months

Monday 10th June
quotequote all
This is a jet ski.

I actually meant solenoid 😂

So on these the ignition doesn’t switch on.

When you put the lanyard in and press the start button the engine should fire then the dash lights up.

It doesn’t anymore, it’s just dead.

Thanks again




Steve Bass

10,364 posts

240 months

Monday 10th June
quotequote all
So the fault is likely in the ignition control circuit.
You're going to have to check wiring/voltage continuity from the battery up to the on/off switch and into the cdi.
But if it won't crank over when you 'switch on' that's the first clue. There's likely something amins in the early part of the circuit that feeds power to the CDI/starter solenoid etc. Get a cheap digital multimeter and get going with tracing the presence of voltage along the circuit....
But first things first, make sure the fuses or master fuse (if it has one) are all ok.

TheHighlander

Original Poster:

1,329 posts

205 months

Monday 10th June
quotequote all
Master fuses are all OK, I fitted new ones anyway.

I have a new start/stop/kill switch coming on Wednesday.

The brown wire you see going into the solenoid is the signal wire to tell the solenoid to fire.

If the solenoid was faulty the power valve etc would prime but it’s stone dead.

I’ve got a multimeter but a little clue less. Facebook has been handy and I have a friend coming tomorrow who knows jet skis inside out but any other help is great.

Steve Bass

10,364 posts

240 months

Monday 10th June
quotequote all
Check if you have a voltage at the on/off switch or start switch.
Put the black lead of the multimeter to the -ve battery terminal, set the DMM to DV voltage (20vdc is a common range) and use the red lead to probe for voltages.

Steve Bass

10,364 posts

240 months

Monday 10th June
quotequote all
Also check if you have voltage present on the red wire pin of the 6 pin CDI connector....

TheHighlander

Original Poster:

1,329 posts

205 months

Monday 10th June
quotequote all
Perfect I’ll get on that tomorrow.

If I go back to it tonight the wife will divorce me.

Thanks again

TheHighlander

Original Poster:

1,329 posts

205 months

Tuesday 11th June
quotequote all
So it’s now running like a Swiss watch.

Traced and checked every cable……….

We put the feed cable on the starter solenoid the wrong way, so it wasn’t feeding the dash it was back feeding as such.

Anyway happy days as it’s problem solved, unearthed a few other issues form the dodgy rebuild the chap I bought it from did but we have sorted them now. Tidied all the wiring and made it look neat and tidy.

Thanks again for your help tho.

Steve Bass

10,364 posts

240 months

Wednesday 12th June
quotequote all
TheHighlander said:
So it’s now running like a Swiss watch.

Traced and checked every cable……….

We put the feed cable on the starter solenoid the wrong way, so it wasn’t feeding the dash it was back feeding as such.

Anyway happy days as it’s problem solved, unearthed a few other issues form the dodgy rebuild the chap I bought it from did but we have sorted them now. Tidied all the wiring and made it look neat and tidy.

Thanks again for your help tho.
Result!!

As an aside, you mention it melted after 3 minutes from the rebuild.
make sure the 2T oil system/pump is working and calibrated correctly...... Otherwise, enjoy thumbup

TheHighlander

Original Poster:

1,329 posts

205 months

Wednesday 12th June
quotequote all
Yep, if you look on the photo the red cable on the solenoid is on the wrong side.

Honestly I just can't believe we made just a rookie error, when we took the cable off to swap it, it naturally went to the side it was meant to go to.

You live and you learn.

I have done a 2 stroke delete so removed the pump and all the lines and we are running it on a good 2stroke premix.