Modern Vespa

Hi all, I hope you each had a good Xmas. I'm about to resume my investigations on this and I'm desperate to get it sorted out as it's back to work for me tomorrow....hopefully not on the train!

I'd like to check the spark plug - just to rule that out - but the HT cable is secured so tightly and with the limited hand-space to manoeuvre in it's really difficult to get to it.

In order to give you all something more to consider, I've taken a short video of what's happening as I attempt to start the scooter. Right at the beginning you can hear the fuel pump prime. Let me know if this sheds any more light on it.

Thanks!

The experts will be here in a little while with a more knowledgeable answer, but I say your problem is with your starter is not engaging. This needs to back to the dealer for this repair if it is still under warranty.

Sounds like the same problem:
Starter is turning and not engaging. Agree, you still have 5 months of warranty.

Ah-ha! At last we have it. Your fault lies in the sprag clutch (a sort of intermediary between the starter motor and the crank shaft). It's not really a DIY job and, as has already been said, it's still under warranty.

Sorry dude, it's the train in the morning. Followed by a call to your dealer. Bummer, but there it is.

@simon64ds I'm just curious and for future knowledge, which part is exactly broken?

Do you mean the connection between the starter gear (number 4) and the crankshaft.


Or do you mean the woodruff key (number 10) / freewheel (number 4)

There is no doubt about it don't try this yourself this is a dealership job with lots of stuff to mess up if you error. Just a poor peice of luck. Capt Gary

It's item number 4 (freewheel) more commonly known as a sprag clutch. It's designed to apply torque in one direction and slip in the other. When it wears (or, sometimes, gums up) it fails to grip and the starter just spins.

Here's a link to sprags in general..

https://en.m.wikipedia.org/wiki/Sprag_clutch

As above, that video nails it - the sprag clutch has jammed open. I've not heard of that before, I've only encountered broken sprag clutches - which make a horrible noise.

Getting the water pump/flywheel cover/stator off is OK without special tools (I did one of ours last week) but getting the flywheel off does require pullers etc, preferably the correct Piaggio ones. I've always let a dealer do that!

As it's under warranty, let the dealer fix it. Just tell them the sprag clutch has failed, and hopefully they can collect the scoot and fix it.

@simon64ds Thanks for the explanation about the sprag clutch.

@Pilaf, you're most welcome Happy New Year!

Many thanks to all of you - I'll follow up with my dealer as it's still under warranty.

I'll post again in due course regarding the outcome, hopefully all good.

Regards!

Spoken by an expert as his sprag clutch went out on a Oyster Tour last year in FLA and his scooter ended up in Atlanta for the repair. But that is another story.

**UPDATE**

Returned to dealer this week and they are currently replacing the starter clutch citing the sprag as the problem. Hoping to have it back in the next couple of days.

Hats off to simon64ds and to all of you kind people on the board who provided support and suggestions.