pulley and sand seal do they work and seal or do you need to machine the case

yep they work, and there's no need to machine the case. I have them on my motors and have had no probs at all.

yep, I;ve fitted a few. No probs yet, I did hear someone calling them 'case wreckers', so maybe some have issues. I always make sure they are super cleaned and glued and tight in the case. On Bluey's flogged 1915, the insert was loose in the case and needed to be shimmed. It has done around 5000km to date, sealed a very leaky engine.

cool banana's for the xmas list then any kits to stay away from

MST is a better version as it has mounting tabs that you can use for small screws to positively secure the insert if necessary, and thier gear seems better than average.

Stick clear of the EMPI one. i had the seal come loose in the slip-in style housing. made a hell of a mess. Smoke out the back in in the cabin on the highway to warwick 2011 made me fear an engine bay fire

Original VW style was for the crank pulley to not be sealed such that air would pass into the case, and vent out the vacuum of the stock breather. If the vw engine is exposed often to excessive dust (eg. baja/buggy offroad), you could imagine where its going to go (eek!). However there was a point to this breathing methodology to reprocess and combust any crankcase blowby and keep it out of the oil.

Bit more of a read here:
http://www.vw-resource.com/air_cleaner.html#crankcase 

I slabbed a loctite equivalent but cheaper 'bearing retaining compound' to assist in holding the seal mount in place.

Word of warning, alot of sand seal kits are listed as having either 6 inch pulleys or don't say anything in regards to the diameter, excluding the important fact that they are smaller diameter than stock crank pulleys (IE: Power pulleys). Of course, this reduces reduces fan speed due to pulley ratio. Insist on 7inch stock diameter style pulley unless you specifically want the power pulley style for your application (Eg: deliberate higher typical engine rpms than stock or short drive duration). And be aware you will need a specific 'sand seal' pulley without the oil slinger swirl, and will need a longer crank pulley bolt.

thanks chris just been onto mst websight and it all looks good its in a manx and there is always huge amounts of dust here in townsville i want to cover all bases before i get her fired up
cheers
stevo

Sorry mate, don't agree with that article. The spiral relies on a close tolerance to the case for effictive operation, I very much doubt there is much air flow through the pulley scroll, the scroll grooves don't even go to the outside of the block (except on type three pulleys)

I have heard that if the seaL LEAKS, it REALLY leaks bad

LEE