I haven’t been using my Manley dipstick for a couple years because I lost the rubber boot. I recently emailed Precision Matters (PM bought out Manley) and they shared the secret PN. This is what they used and it’s a perfect fit. Ace hardware had the “old style” and the “new style” so I bought both. New style has a shorter skirt but either works fine.
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Thanks Michael. I've never had one on mine ..............

Sorry but confused what is the function of this part ??

It seals the Manley dipstick thermometer to the engine dipstick tube

I picked this bus dipstick seal at a local VW shop. It forms a good seal over the tube.
$5.00 at my local VW store....

The Delta seals are $4.47 and in stock at my local Home Depot.

Thanks for sharing Michael !!

Mine has a tear in it so I'll be stopping at Home Depot today