OP
@cuba avatar
UTC

Hooked
Vespa Cosa 200, GTV 250
Joined: UTC
Posts: 155
Location: Belgrade, Serbia
 
Hooked
@cuba avatar
Vespa Cosa 200, GTV 250
Joined: UTC
Posts: 155
Location: Belgrade, Serbia
UTC quote
Hi there!

Yesterday they finally brought my "new" '97 PX150E.
She is in veeery good condition, most of the details look brand new,
xcept for the rear shock - pretty rusty.

The only problem is - she doesn't start.
No spark.

Changed the spark plug, stripped terminals - no signs of life.
there's a suspicious-looking fuse, seemed like it was made from several different fuses, and it is broken from one side.

May this be a problem?
UTC

Ossessionato
Joined: UTC
Posts: 2633
 
Ossessionato
Joined: UTC
Posts: 2633
UTC quote
It's more than likely your CDI (it's blue maybe black). I have a 2005 PX motor and it didn't have spark..changed the CDI and then got spark. Try to find a doner CDI that is working and see if you get any spark.
@rover_eric avatar
UTC

Moderator
1965 Vespa SS180, 1963 Lambretta LI150
Joined: UTC
Posts: 6980
Location: Detroit, Michigan
 
Moderator
@rover_eric avatar
1965 Vespa SS180, 1963 Lambretta LI150
Joined: UTC
Posts: 6980
Location: Detroit, Michigan
UTC quote
It's not your fuse.

Think of a vespa engine like this : The engine can run completely independent of any and all electrics. The battery and wiring harness are all there to just put juice to the horn and lights.

Now, what i would do to troubleshoot your spark problem :

The CDI is the little blue or black box that hangs off the back of your engine. It takes impulses and charge from the stator, and triggers the spark. There are 4 colored wires running INTO the CDI, and your sparkplug wire running out of it.

Uplug the outermost GREEN wire... the one closest to you and furthest from the engine. This is the contact that runs to all your kill circuits. If this tab gets grounded out, then you will have no spark. Therefore, if your stator is working, and your CDI is good, if you have the red / white / green wires running to your CDI and are not getting spark at the plug, then that's where the problem is isolated : plug, wire, CDI or stator.

If you pull the green wire on the outside and suddenly you have spark, then your green wire there is grounding out somewhere upstream.... this wire runs to your kill circuitry, so either the one on the handlebar or the ignition switch on the column are grounding out when they shouldn't be.
UTC

Ossessionato
Joined: UTC
Posts: 2633
 
Ossessionato
Joined: UTC
Posts: 2633
UTC quote
Rover Eric wrote:
It's not your fuse.

Think of a vespa engine like this : The engine can run completely independent of any and all electrics. The battery and wiring harness are all there to just put juice to the horn and lights.

Now, what i would do to troubleshoot your spark problem :

The CDI is the little blue or black box that hangs off the back of your engine. It takes impulses and charge from the stator, and triggers the spark. There are 4 colored wires running INTO the CDI, and your sparkplug wire running out of it.

Uplug the outermost GREEN wire... the one closest to you and furthest from the engine. This is the contact that runs to all your kill circuits. If this tab gets grounded out, then you will have no spark. Therefore, if your stator is working, and your CDI is good, if you have the red / white / green wires running to your CDI and are not getting spark at the plug, then that's where the problem is isolated : plug, wire, CDI or stator.

If you pull the green wire on the outside and suddenly you have spark, then your green wire there is grounding out somewhere upstream.... this wire runs to your kill circuitry, so either the one on the handlebar or the ignition switch on the column are grounding out when they shouldn't be.
HA...then I have a grounding out problem somewhere. I was able to pull the green wire and still have it start! I also can't get my headlight to work at the moment either I know now I have a grounding out problem. I suck. Sorry to hijack the thread.
@rover_eric avatar
UTC

Moderator
1965 Vespa SS180, 1963 Lambretta LI150
Joined: UTC
Posts: 6980
Location: Detroit, Michigan
 
Moderator
@rover_eric avatar
1965 Vespa SS180, 1963 Lambretta LI150
Joined: UTC
Posts: 6980
Location: Detroit, Michigan
UTC quote
what i mean is ...

with the green wire on the 4th tab...if you have NO spark...

...and then you pull that tab and HAVE spark, then either your kill switch circuits are engaged ( which , really, this is the way you WANT it to work ) ... or if all of your switches are set to RUN, then likely your green wire is grounding out somewhere along the way. All it has to do is for a stripped part of the wire to touch the frame when the 4th green tab is connected and you won't have any spark at the plug.
UTC

Ossessionato
Joined: UTC
Posts: 2633
 
Ossessionato
Joined: UTC
Posts: 2633
UTC quote
Rover Eric wrote:
what i mean is ...

with the green wire on the 4th tab...if you have NO spark...

...and then you pull that tab and HAVE spark, then either your kill switch circuits are engaged ( which , really, this is the way you WANT it to work ) ... or if all of your switches are set to RUN, then likely your green wire is grounding out somewhere along the way. All it has to do is for a stripped part of the wire to touch the frame when the 4th green tab is connected and you won't have any spark at the plug.
Can you come over really quick and fix my scoot? Clown emoticon
OP
@cuba avatar
UTC

Hooked
Vespa Cosa 200, GTV 250
Joined: UTC
Posts: 155
Location: Belgrade, Serbia
 
Hooked
@cuba avatar
Vespa Cosa 200, GTV 250
Joined: UTC
Posts: 155
Location: Belgrade, Serbia
UTC quote
thanx, guys

she is at the dealer's right now.
they got problems with all their mechanix being on vacation or badly ill,
so nobody can really fix my vespa

tomorrow i'll try to go there and try it myself
OP
@cuba avatar
UTC

Hooked
Vespa Cosa 200, GTV 250
Joined: UTC
Posts: 155
Location: Belgrade, Serbia
 
Hooked
@cuba avatar
Vespa Cosa 200, GTV 250
Joined: UTC
Posts: 155
Location: Belgrade, Serbia
UTC quote
it turned out to be hall sensor fault.

now it's fixed allright, and tomorrow i'll pick her up))
@rover_eric avatar
UTC

Moderator
1965 Vespa SS180, 1963 Lambretta LI150
Joined: UTC
Posts: 6980
Location: Detroit, Michigan
 
Moderator
@rover_eric avatar
1965 Vespa SS180, 1963 Lambretta LI150
Joined: UTC
Posts: 6980
Location: Detroit, Michigan
UTC quote
Stator problem... makes sense.
DoubleGood Design banner

Modern Vespa is the premier site for modern Vespa and Piaggio scooters. Vespa GTS300, GTS250, GTV, GT200, LX150, LXS, ET4, ET2, MP3, Fuoco, Elettrica and more.

Buy Me A Coffee
 

Shop on Amazon with Modern Vespa

Modern Vespa is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com


All Content Copyright 2005-2025 by Modern Vespa.
All Rights Reserved.


[ Time: 0.0136s ][ Queries: 3 (0.0047s) ][ live ][ 327 ][ ThingOne ]