LCGB Forums

Problems starting.
I have a GT186 that I have recently had rebored. Also added new Scootronics AC stator and changed reed petals whilst scooter resprayed. The carb - 25mm Dellorto PHBL - is unchanged and has not been an issue for the past 15+ years. I have stripped down the carb and cleaned the jets out - no problems there. Have a good spark. The problem is that i cant start the bl00dy thing. Timing is set, petrol is flowing through to carb (float bowl has fuel in it). But i dont seem to be geting fuel through to piston/barrel - the plug does not appear to be wet. I did spray some cold start into carb mouth and it started up with one kick.

Any advice/thoughts welcome.

P.S. Choke is definitely working.

You did put the piston the right way up? You could try putting your hand over the carb open when you kick it to draw the fuel through

old/stale fuel ?

Try another carb'......

The changes you have made should be the first thing to check:

dexy wrote:
I have a GT186 that I have recently had rebored. Also added new Scootronics AC stator and changed reeds

Any advice/thoughts welcome.

I would suggest in reverse order, including a leak test.

When checking the ignition, strobe it with plug out via an electric drill fitted with a 17 mm socket to spin the flywheel (preferably with clutch lever tie wrapped fully in) to see if the timing dances about.

As for the top end, if you've built it thoroughly, you will know bore clearance, ring end gaps, squish etc & whether the port edges were deburred

If you do not know the last details, then I would strongly suggest the top end is taken apart so that it is re-assembled to the optimum. Unfortunately, it may be too late for the rings.....

You say you fitted a new stator any reason for the change prior to rebuild ? if the old stator wasn’t faulty maybe try it with that one ?

Thanks for the responses. Everything was double checked on topend as i went through the rebuild so i am very confident with that. My BGM stator let me down half way through the National Road Rally - second BGM stator in 2 years - but I have faith in Antonys stator, at least it looks like a decent bit of kit alongside his other components.
I have the same carb on my other scoot with GT kit so i will swap over. My concern is the petals - can these cause an issue?

dexy wrote:Thanks for the responses. Everything was double checked on topend as i went through the rebuild so i am very confident with that. My BGM stator let me down half way through the National Road Rally - second BGM stator in 2 years - but I have faith in Antonys stator, at least it looks like a decent bit of kit alongside his other components.
I have the same carb on my other scoot with GT kit so i will swap over. My concern is the petals - can these cause an issue?

Yes if they are broken

try a squirt of oil down plug hole and kick it over a time or two to seal rings before trying to start it