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vespa px woes
Posted: Mon Aug 20, 2012 6:16 pm
by joeswoonara
I have a Px that is in danger of going to a watery grave ............it rides great for about 5miles then stops ! If i leave ot a couple of minutes it starts 1st kick then its o.k for another few miles and then stops again .........stator i thought so changed that ......and the c.d.i plug and plug .....the tanks been cleaned .....so now spotless .........carb is ok and jet blown out...........i'm now stumped.......please help save this px from the local cuto

Re: vespa px woes
Posted: Mon Aug 20, 2012 6:47 pm
by cit205
Petrol cap breather blocked or something like waterproofs stashed under seat blocking it or the air intake
Take the cap off and ride down the road ,if the tank's not full ,that will eliminate if it is the cap if you havent got access to a compressor or something to blow it through .
Could still be a faulty LT coil on the stator ,just because it's new doesn't mean it's not faulty, same with CDI, or your switch, try pulling the green wire from the right hand terminal on the CDI to bypass the switch to eliminate that. Obviously you'll have to stall it to turn it off while you do that test.
Re: vespa px woes
Posted: Tue Aug 21, 2012 10:51 am
by joeswoonara
Thanks for the reply ......no waterproofs in the way,forgot to put pettol cap breather as been drilled out larger will try the green wire tonight ..........the stator was change again for a know working pne off a running scppt and it still stopped
Re: vespa px woes
Posted: Tue Aug 21, 2012 11:06 am
by rapido230
float needle sticking? or worn? maybe too long a fuel pipe or kinked?
Re: vespa px woes
Posted: Tue Aug 21, 2012 11:12 pm
by joeswoonara
I have swapped carb with like for like with a mates ......still konked out .......fuel hose is the BGM type with internal spring so should'nt kink.............looks like the canal for this baby a

Re: vespa px woes
Posted: Wed Aug 22, 2012 8:40 am
by rapido230
isnt the bgm hose slightly smaller internal diameter? i could be wrong tho and i'll be corrected on here lol. what about length of pipe ? sometimes if too long it can cause probs. dont throw in canal, throw it my way lol
Re: vespa px woes
Posted: Wed Aug 22, 2012 2:04 pm
by LI150
I cant answer your problem but from what you are describing it sounds like its a problem once your scoot is warmed up. Seeing as it runs ok then when warm problem occurs I would say it is not a fuel prob. Just a thought are you sure its not heat seizing
Re: vespa px woes
Posted: Thu Aug 23, 2012 11:22 am
by cit205
That's what made me think cdi or LT coil..
Wonder if there's a hairline crack somewhere in the casing where it counts ,that opens up when it gets to temperature, just a thought

Re: vespa px woes
Posted: Thu Aug 23, 2012 11:30 am
by mongoose
You have changed the plug, but did you change for the same. I would go a couple cooler if you can. See if it runs for longer, to me it sounds like the coil is breaking down. Also when you go out next, drive really conservatively, keep revs low and see if that improves distance, i had a car once which would go all day long unless i went over 55 and the same thing happened, few minutes later it would all start fine. That was the coil but never bothered to change it.
Re: vespa px woes
Posted: Fri Aug 24, 2012 10:27 pm
by joeswoonara
hi lads ....thanks for the replies and i can see what your all saying ,but thats the thing that has got me so baffled ........the c.d.i is a new one so to is the stator plug lead, plug cap and even the carb although not new was taken off a mates running scooter ,all the parts you have mentioned have been changed for new after it started conking out