750SS petrol tank filler cap seal
 

Hi,

after having changed my 750SS' fuel filter I am about to refit the filler cap. I've read about the reluctance of the seal to stay in place during this process, and applied a little gasket sealant to help with this. However I am a bit insecure whether I've positioned it correctly (above the grub screw holes) due to the force needed to squeeze the cap in place. I'll try to attach a picture, and if it shows up I wonder if any of you can confirm whether the seal actually is the correct one for the 750SS filler cap, and if it is in the right location?

Many thanks

Nope - it should sit around the outside of top ring, so you can see it when fitted.

They are bloody tight when new, and really awkward to fit. Having at least three hands is the way to go! They seem to just pop off by themselves as they're under pressure.

I found myself using a mallet wedged between the filler ring and my chest to apply pressure onto the filler ring, leaving both hands free to guide it all in place and tighten the grub screws.

You're also missing the big O-ring which sits in the groove below the grub screws in your pic ... unless you've just not fitted it ;)

Many thanks for your quick reply! I thought my first refitting attempt definitively looked better than how he seal has sat for many years, down and around the O-ring, courtesy someone who serviced the bike for a previous owner. I think the abuse that seal has suffered must have made it easier to relocate over the edge of the filler cap, which I actually didn't find too difficult.

Yes, not yet fitted in that photo. For the sake of completeness, here is another shot taken before I put the filler cap back on:

Yep, that looks perfect!

The challenge now is to get the bugger back in and tightened up... ;)

I once read that putting the filler cap in the freezer for a while shrinks it just enough to help it fit. I never tried so don't know if it will work or not. Could be worth considering....

Clean the Steel sealing face of the tank (Scothbrite or wire wool should do nicely) and apply some RED grease or something similar (I use Hellerman oil) to the O-ring to help things slide back in to place

I'm having a similar problem getting the cap and seal into a position where I can tighten the grub screws. Just when I think I've got it into position and start to tighten, the thing pops back out again!

On closer inspection looks like the seal has lost its elasticity so does anyone know where I can get hold of a new seal?

Should be able to get one from your Ducati dealer for about £6

If not try here
http://www.italo-shop.com/product_in...g-schwarz.html

SS tank seal ...easy !
 

From experience with mine, Ant's, Vespa's, and others, I have always used 3 or 4 'spots' of superglue and glued the seal to the ally casting. Then used a coating on the tank and the seal of brake cleaner to ease the thing back in the tank! SIMPLES ;-)

Thanks guys