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I've had an idea to tidy up my 2.2 vac system a little more and hopefully make it even less prone to leaks.

Can any of you kind people post some pics of the connections for the vac pump, brake servo and vac reservoir on the 110 and the 90 flavour engines.

In a nutshell I want a single pipe off the pump directly to the servo, a 'T' to the reservoir with only 2 outlets to swirl actuator and turbo EV.
If I can do it with no blanked pipes it minimises potential leaks and makes the modifications even harder to spot on an MoT.

Thanks in advance as always

Just one thought, with only 2 EVs it is known safe to bypass the vac reservoir. It's a common source of vac leaks so don't discount it from your investigations

Has no-one ever thought that the Vac Pump itself could wear out and not do its vac'ing as good?

I remember ages ago someone on here with a 110 had a new Vac Pump fitted (it cost about £65.00?) and it sorted out ALL the running issues, I know these pumps aren't talked about much here but just to throw some confusion into the mix......

Funnily enough I've just been around my LMF's to source a vac gauge and pipe to no avail.
I'm either going to have to order on-line or nip round to a local friendly garage and bung him a few beer tokens to borrow a gauge for 10 minutes.

Once I've tested and hopefully eliminated the pump I have considered bypassing the reservoir but was a little concerned about any leaks killing the servo feed. It would be very simple to do as I could use the blanked off conection from the pump to supply the swirl EV and the spur off the servo that feeds the reservoir could easily be redirected to the turbo EV. 2 minute job and easily accesible but there is the braking to consider.
Do the vac pipe connectors on the pump and servo have check valves to give the servo max vac when you hit the stop pedal?

It's my understanding from the vac system diagram I posted a while back that the reservoir is there to provide vac to the rest of the vac system whilst the brake servo is using most of it from the pump. It is not there to provide vacuum to the servo in the case of other parts of the vac system also using vacuum.

This is the only way it makes sense due to the presence of the vac restrictor between the pump/servo and reservoir.

Does that make sense?

Given this, it makes absolutely no difference to braking safety or reliability if you remove the reservoir. It can only affect things "downstream" of the restrictor, ie. the rest of the vac system (EVs etc).

Sorry if that's not clear, let me know and I'll try and rephrase it!

Jon,
that makes perfect sense, my concern was that there is a 2 way connector on the pump, 1 direct feed to the servo and a feed to the dozer EV which is now blanked on my car. If I use that feed for the swirl EV and at some point a pipe split or the EV or actuator failed would it dangerously drain vac pressure to the servo.
Logic says it should be ok as Pug already used that feed for an EV but I'm being captain cautious as I quite like the front end of my car the shape it is now without lamp post shaped modification
Having said all that regardless of where the pipework is routed a split pipe is going to throw a spanner in the works so I might just try it, the turbo EV should be easy to do a quick check on without a gauge as it should have a strong vac at low revs and lose pressure as the turbo kicks in. Just hope it doesn't try to suck my finger down the pipe! I believe the swirl EV is the opposite but can't picture it in my head until I pop the bonnet later.
Just need to source some vac pipe so I can rule out the pipework.

Totally understand. Looking at the vac system diagram, the feed from the pump to the doser includes another vac restrictor. If you decide to use this feed for the swirl EV (which I think is a great idea) then retain this vac restrictor.

I agree that if you have a vac leak upstream of this restrictor then it could cause a total loss of braking assistance, but this is no worse than how the car left the factory so I wouldn't be too concerned. If you replace the vac hose and keep the length of pipe between pump and restrictor as small as possible then I think you've done the absolute best you can.

You're right that the swirl EV is opposite, it applies vac to the diaphragm to close the flaps and releases it to open them (i.e. they default open). Bear in mind therefore that engine off means flaps open, and they should close as the engine starts. You can therefore test vacuum at the swirl EV output with the engine on but idling, you should get 800-850mb vac there.

Good luck