Splitting and Rebuilding a VBB engine, What to look out for?

[antvespa]

Hi,

New to the forum but have been reading lots of posts and it appears there is a great amount of knowledge on here. 

Myself and a friend are rebuilding 2 Vespa VBB's from the ground up, learning along the way but are having a lot of fun doing it. 

We have stripped the frames and they are off to get media blasted to get rid of any nasty paint and rust, using a company in Essex called ctc-powder-coating.co.uk - Guy called Trevor was very helpful. 

We are now turning our attentions to the engine. 

Both covered in gunk and dirt but have cleaned them up and there appears to be no cracks in the casings, which I'am happy about. 

For some reason I can push down the kickstarter to turn it over unless I help it along by rotating the flywheel a bit.
Any ideas what this could be? Clutch or gearing stopping me from doing this?

When we open up the casings is there anything to be looking out for to see if they are all ok to start the rebuild? 

We plan on changing all of the seals and bearings throughout the engine so its fresh and new. 

Any help, tips and recommendations would be great. 

Thanks
 

[henri]

remove all bolts between cases ,especially the long one thru swinging arm . if any are seized in your cases wont split . heat around the locating dowel at bottom an around the cases were crank comes thru on both ends .depress kickstart a 1/4 turn an wiggle that whilst tapping around with a rubber hammer . eventually cases will split apart . dont pry in the gasket faces an no big hammer blows either , rubber mallet only . H

[antvespa]

Thanks for the tips.

Anything to look out for once the cases are opened? Where to look for damage or wear?

[bryno]

Nice project

The rotary sealing pad is where you don't want to see any real scores, cross your fingers on that one, apart from that if you are changing all the seals and bearings nothing major other than check for cracks or damage from prior mechanics!

Presume you are replacing crank shaft?

That is a bit of a faff on the VBB due to the main bearings they use, makes getting it all back together a bit of a challenge, but a DIY job for sure.