Dissy vac advance full of oil

[Stesaw]

Title says it all, been trying to track an annoying hesitation the van has developed over the last month. Seems to be fine when warm, but from cold it bogs down and doesn't want to know. I tried sucking on the dissy and nothing moved. I've swapped the tube and still the same. I removed the dissy today and when I turned it upside down this came out.
I'm assuming the diaphragm is cream crackered. And I need to swap it out.

[davidoft1]

There’s no oil in the vacuum unit or any way it can get in there really, try draining it and see how it operates, could be a buildup of oil
Vapour over time perhaps

[Stesaw]

Thanks David, I thought it was odd lots of oil came out of it I'd assume any liquids gonna affect a vaccum. The arm on the unit itself feels very stiff and doesn't plunge well, there is barely any movement and it only seems to want to move sideways if that makes sense. If I push it and put my finger over the vac line port It holds a small vaccum for about 30 seconds then there's nothing.