QJ Yamati Eurostrada 49cc electrical possible short? By jumpinjohn (Read 1,508 times)

[jumpinjohn]

Hi, first time poster.

I have a friends scooter I have been working on and am nearly done.  It's been fun learning how everything works, and rebuilding the broken issues.  This scooter is low miles under 2000.  She is the original owner, and I think I am only one who has worked on it.  I just replaced a number of things.  Clutch, carb, intake, starter, throttle switch assembly.

Thats where I am stuck now.  When the bike was broke, the starter was very over worked especially when the clutch was sticking and other issues keeping it from starting.  I replaced the starter.  I'm thinking I may need a solenoid.

Here's the issue.  The new throttle assembly was wired a little different, so I had to change a ew wires around in that connector.  I think I have it right.  When I look at the connector on bike with the locking clip on bottom.  
The lower left is constant power.  The lower right goes through the cranking button and puts out the 12 v.  The two upper wires go to the run/no run switch.  As of now, those two wires appear to be grounded. (not sure if they should.

OK when I hook everything up, The solenoid does engage and lock.  I get 12 V out, but if I connect the starter, I get only 8 v there.

The issue seems to be that when I push the cranking button, I seem to be getting a slight reading of voltage through the ground/frame.

Could a bad solenoid cause this?  It's driving me nuts here...If you know electrical, PLEASE help.  I have a volt meter and a test light and slightly know how to use them.

Oh by the way this scooter came with a alarm installed.  The owner had no idea.  I pushed the buttons on the key fobs and it went off.  It also has remote cranking through the fob.  

This scooter always had trouble starting.  I knew it had issues with intake leaks and carb gummed up.  But now I am thinking the spark always looked a bit weak, perhaps it always had a short.

Last week after installing all the parts (before new starter) I was able to kick start it (first time for that) and ride.  Sadly the kickstart lever stripped out.  I'd like to get this working with alarm, but in the end if I need to bypass it or the switches I would.

Thanks in advance for all of your help.

John
Stuart, Florida
72 BSA-650 Lightning
78 CB-400 Hondamatic
77 Fantac moped 

[alleyoop]

Do you have a Ground wire from the NEG POST of the battery to the FRAME? Do you have a Ground wire from the MOTOR to the FRAME?
The Solenoid only has Two Wires 1 Terminal has the Positive Thick Cable from the Positive
Post of the Battery the Other Terminal on the Solenoid goes to the Starter.
Alleyoop

[jumpinjohn]

Yes that is all as it should be. Both are grounded to the bolts holding the coil.
If I jump it, I get the 8v at the starter. 12 if I unhook the wire from the starter


I'm thinking there's something going on inside the solenoid because it is getting hot. From what I have seen the other 2 wires going into the solenoid are a ground, and the positive from the start button. Could something in there be shorted?

Is there a specific test to test it, or is it serviceable at all?
Anyone know how many volts should be going into the small wire into the solenoid (when the start button is pressed)

[alleyoop]

That is NOT the way it works.
When you squeeze the BRAKEs EITHER BRAKE it sends voltage to the solenoid and when you PUSH THE START button it GROUNDS the SOLENOID and the circuit is complete and activates the contact inside to TOUCH BOTH TERMINALS of the SOLENOID from the inside to PASS 12volts to the STARTER. JUST AS IF YOU TOUCHED BOTH TERMINALS FROM THE OUTSIDE.

So the test is THIS touch BOTH TERMINALS with a WIRE or SCREWDRIVER and see what the WIRE on the starter is getting. It will spark when you touch the two terminals but just hold it on it will only spark once as you touch both of them.

YOU MAY HAVE NOT ENOUGH THICK OF A WIRE from the SOLENOID TO THE STARTER.
Alleyoop

[jumpinjohn]

Thanks again.
I took it out so cant check it right now, I'll try tomorrow. Do I have to have the harness from the solenoid plugged in while I do that?

Should one of the wires going to the start button have 12v? (As of now I do) If not, could once again the solenoid be sending 12 back down that line if it's bad?

John
Stuart, Florida
72 BSA-650 Lightning
78 CB-400 Hondamatic
77 Fantac moped

[alleyoop]

No, the only 12 VOLTS is to the IGNITION KEY SWITCH and that should come from the THIN RED WIRE with a FUSE ON IT right off the POSITIVE TERMINAL of the battery. Did you rewire this thing or something?

The way it works is YOU TURN ON THE IGNITION WHICH ALWAYS HAS 12VOLTS straight from the battery.
It makes contact with a BLACK wire that then connects to all the other things on the scoot that needs 12volts to work, BRAKE SWITCHs, LIGHTS, GAUGES etc..

The START BUTTON ALL IT DOES IS GROUNDS THE SOLENOID that is all it does it should not be live.

[alleyoop]

YOU DO NOT HAVE TO HAVE IT PLUGGED IN TO THE HARNESS to do the test of touching both terminals to check the voltage at the starter. The plug connects it to the BRAKE SWITCHS and the START BUTTON that is all.

No, the only 12 VOLTS is to the IGNITION KEY SWITCH and that should come from the THIN RED WIRE with a FUSE ON IT right off the POSITIVE TERMINAL of the battery. Did you rewire this thing or something?

The way it works is YOU TURN ON THE IGNITION WHICH ALWAYS HAS 12VOLTS straight from the battery.
It makes contact with a BLACK wire that then connects to all the other things on the scoot that needs 12volts to work, BRAKE SWITCHs, LIGHTS, GAUGES etc..

The START BUTTON ALL IT DOES IS GROUNDS THE SOLENOID that is all it does it should not be live.

[jumpinjohn]

Thanks for the thorough explanation. I did not rewire the bike. I went ahead and ordered a solenoid. I would not be surprised if it's shot because it was used a lot. The bike probably spent more time cranking than driving!

If it's not the solenoid, then it must have something to do with the hook-up of the starter button and kill switch. I do know someone had actually physically removed the slide off the kill switch before, and told her not to touch it. I forgot she had told me that long time ago.

It may be helpful if someone could tell me what color wires come up into that plug and where they go. It's funny I have 3-4 of the throttle assemblies and they are all different color setups. I had a hard time getting the correct one for the cable that has the plate and screw to lock it in. Anyway, that connector now has one 12v going in, from what you are saying it should not be +. I'll try to post a pic later.

John
Stuart, Florida
72 BSA-650 Lightning
78 CB-400 Hondamatic
77 Fantac moped

[jumpinjohn]

I'm looking at this, and doesn't it contradict what you told me alleyoop?

[alleyoop]

Yes that diagram is wrong the BRAKE SWITCH is the one that SENDS voltage to the STARTER RELAY. Not the KEY ON. If that where the case then all you would need is to turn the KEY ON and push the start button.
ALleyoop

[jumpinjohn]

Well I just found another issue, that may be causing my trouble.
The new starter has the wrong shaft. The old one had 10 splines, this one is slightly larger with 9.

I hooked up the old one, and it is working most of the time. I guess it has a dead spot on the armature, because if I twist it slightly, it works again. (It was doing that before, I would slightly kick to move it.

I swear just about every part I have ordered for this clone has been close but not right!! eerrrr

So I am going to try to return/exchange this h/o starter. Until then I guess i will quit troubleshooting it.

Happy 4th everyone!

[jumpinjohn]

According to that diagram, When the key is on, current flows to the brake switches, when squeezed the brake switch allows current to flow to the side of the push button start. When that is pressed current goes to the solenoid.

Is it possible my scooter is different than what you speak of? This Yamati QJ seems different in many areas. That's why I keep getting wrong parts.

I'm having problems finding a starter for it. Anyone know where I can get one that has 10 teeth and 64mm bolt hole spacing (not 70)

John
Stuart, Florida
72 BSA-650 Lightning
78 CB-400 Hondamatic
77 Fantac moped

[alleyoop]

Well I never heard of a scoot working that way. So maybe someone else will chime in and verify it or not.

BUT I DO HAVE TO SAY that is not a common hookup. What I think you have wrong is the SOLENOID WIRES REVERSED either on the plug and or you messed with the wiring.
Alleyoop

Here is your common SOLENOID and the wires, GROUND GOES TO THE START BUTTON and the OTHER GOES TO THE BRAKE SWITCH which be be LIVE when you squeeze the Brake Either Brake by the way.

[jumpinjohn]

I still haven't found a correct starter for this scooter. Can anyone help??

I was going to rebuild it, but the armature tested bad, and the brush holder somehow got cracked. eerrr

I've "heard" that the 9 and 10 tooth are interchangeable, but it doesn't make sense to me. Would I need to change the gear inside the engine that the starter engages into?

[JR]

You are correct Alley, while that diagram is on a very few scooters it is not typical. The typical scooter starting system uses a start button that after the brake light handle is squeezed completes the circuit by sending ground to the starter relay solenoid.

JR