Page 1 of 1

GP Cutting out

PostPosted: Fri Jul 31, 2015 4:44 pm
by warniep
Hi
I'm new here having just purchased a 1970 GP 150 and have been out of the scooter scene for a long time. I was out on the GP and the engine cut out, it didn't splutter or anything just stopped running. I had a look but couldn't find the problem. I have stripped the carb and cleaned it out. Tried it again and after a bit same problem. If I leave it, it will start after about 10 minutes. I was told to check the stator with a multi meter, I should get 400 on the green wire and 90 on the red wire. I'm getting 449 on the green and 96 on the red wire. Could anybody tell me if the higher reading are the problem ? I would be grateful of Any assistance. Thanks.
Paul.

Re: GP Cutting out

PostPosted: Fri Jul 31, 2015 8:29 pm
by coaster
Both those readings are normal, 400 would be WAY too low. I'd be inclined to try it without the petrol cap on in as blocked breather holes cause exactly the same problem, as does an obstructed inlet scoop under the seat. Next check that you are getting a good flow of fuel by taking the fuel pip off the carb and running the tap into a container. It should flow freely something like a pint per minute.

PS. you're supposed to introduce youself in the welcome section first, welcome anyway ;)

Colin

Re: GP Cutting out

PostPosted: Fri Jul 31, 2015 11:37 pm
by Mal*1
My GP did this... After messing about with all sorts, I adjusted the needle a notch... Worked a treat!

Hope you solve soon.. :D

Re: GP Cutting out

PostPosted: Sat Aug 01, 2015 7:13 am
by Jim Rose
Try a spare CDI / Coil these sometimes cut out when they are breaking down.

Re: GP Cutting out

PostPosted: Sat Aug 01, 2015 8:29 am
by Knowledge
coaster wrote:PS. you're supposed to introduce youself in the welcome section first, welcome anyway ;)

Colin


Col,

I think you are thinking that this site is Scooterotica. The LCGB forum has no welcome section.

The fuel starvation issues commonly cause scooters to splutter to a halt, while this scooter just dies. I'm thinking it is more likely to be electrical: low tension coil or pick-up on the stator. They are both a bummer, but good replacement items should be sourced. You can still get pick-ups in Piaggio bags, which are supposed to be good, but there are no Piaggio LT coils available. It is worth trying to source a second hand Italian Piaggio stator in order to steal the LT coil from it.

Good luck and don't give up; this problem can be solved.

Re: GP Cutting out

PostPosted: Sat Aug 01, 2015 10:57 am
by coaster
Knowledge wrote:.....I think you are thinking that this site is Scooterotica. The LCGB forum has no welcome section.


Oops, my bad :oops:

Re: GP Cutting out

PostPosted: Sat Aug 01, 2015 8:11 pm
by rossclark
I looked at sourcing Piaggio stators as donors but even they're pricy now.

You'd think there'd be hundreds around too, but it just seems not to be the case.

Re: GP Cutting out

PostPosted: Mon Aug 03, 2015 4:12 pm
by warniep
Thank you all very much for your replies. I will have a look at the solutions you have provided and work through them and hopefully sort the problem out. I will keep you posted.
Paul.

Re: GP Cutting out

PostPosted: Tue Aug 04, 2015 9:37 pm
by sunrisemac
I had the same thing happen to my gp150 when I first used it after a restoration, it turned out to be a dodgy connection on the condenser wire, it appeared to cool down a bit and make a contact but when warmed up the wire was moving just a wee bit and stopping the engine, it took me ages to find it as everything looked OK.