Problem with pump.

The main problem seems to be the conical shape of the nipple. When the jubilee clip is tightened it only presses on a very small part of the conical nipple so there is in fact very liitle grip exercised by the clip, which cannot bend across it’s width

So possibly the way to go is to use tape that is rolled over onto itself to make up the conical shape to a level surface for the clip to place pressure on the whole of the nipple

Or for a realy fiddly job, build up a piece of base tape in sections along it’s width to take up the bevel.

Plastic insulating tape will give you more width than you need and is made to stick permanently. So you can easily build up to whatever diameter you need for a good fit.

It would be best to make it up on a flat surface, then attach it to the nipple .

Thanks to all you guys for helping, I really appreciate it.

I had some self adhesive medical tape so I cut a tiny piece that I wrapped around the conical nipple on the pump (some of you guys must use a metal Mityvac, does it also have a conical nipple?) then put the hose on over it and tightened the jubilee clip.

This stopped the hose from coming off but I would lose vacuum ever so slowly.
I had another go and made a better job of it and it holds vacuum now so I am very pleased.

As you said Petit I need to be careful not to crush the nipple or else I will need a new pump.

Prent: Yea, you can buy a very small tube in most hardwares, but sometimes they have it in the marine stores like West Marine. The stuff is great but does dry up and set inside the tube even though it may be airtight. Humm I didn’t think the tube was oversized for the nipple of the pump. Why not just a much smaller plastic tube then. Probably has something to do with the male coupler to the cylinder. Whole new puzzle, but I like puzzles anyway.

Steve.