brake problem

[MrBigMac]

I have a problem when I brake the pedal goes hard. Rock hard. the brakes seem to stop the car. Anyone have any ideas.

[Magenta Sunset]

servo? Vac hoses? Vac pump? (guessing here)

[MrBigMac]

I bet I've dropped the seal when I unplugged pipe of vacuum pump when I fitted my fmic

[306Dan]

If thats not the case, the flexi on the vac line may be split under the braid

[MrBigMac]

I think its the pump as it barely sucked my finger on it. Does anyone know what vacuum I should see on a gauge ? I think for piece of mind I may just change the pipes for that reason ?

[MrBigMac]

Does anyone know what vacuum the pump should be making ? I have a gauge to test it but cant find the info. Thanks

[Piggy]

It should make a fair amount tbh

Should try n suck ya skin off like a hoover

[Toms306]

A Hoover or a Dyson? Very different suction levels.

[highwayman306]

A Hoover or a Dyson?  Very different suction levels.

Very true

[Niall]

It should make a fair amount tbh

Should try n suck ya skin off like a hoover

Hmmm not always. Generally they do not need huge amounts of vacuum to work effectively. You could probably suck on the pipe and they would work fine.
I would suspect if you have been bending the hose around its split.

[Poodle]

Have you unplugged the pipe to the egr/air doser? Those need blanking well if you have, i had this problem because i'd used a screw that wasn't big/aggressive enough and it leaked.

[MrBigMac]

That was all removed years ago. I added some sealant to the screw I blocked pipe with. Il double check tho ?

[Redordead89]

A Hooker or a Dyson? Very different suction levels.

Lol

[Poodle]

That sounds pretty sealed tbf lol, got a smoke machine? That'll test everything for leaks, i've seen a couple rust through on the metal pipes too, unlikely but something to bear in mind.

[mad306man]

This problem just started happening to me yesterday.

Could've sworn I heard a pop as I braked pulling up, and the pedal went rock hard, exactly the same as if you were pumping the pedal with the engine off.
No servo assistance until you pull off and apply some load to the engine, then it works again.
If you prolong engine overrun, say down a hill and apply the brakes lightly, you soon run out of vacuum and the brakes are crap by the time you actually need to stop.

Need to get this sorted, so will check vac pump/hoses/one-way-valve later on.

Is the vac pump the round thing above the gearbox on the end of the camshaft?
Looks like it only has the one connection, or is there another underneath that I can't see?

I guess if the servo diaphragm had gone, then you'd get no servo assistance at all?

[pug306driver]

could someone put up a picture/exploded view of the vac pump internals, its a rotor type puns has carbon vanes?? cam shaft driving...what drive type does it have, dog and bone or splines?? also how is it lubricated.

have heard some noise when engine cold and listening under bonnet, some noise but not much from that area on ours.....brakes are fine at the momentt thank god.

as this pump is pulling in air when brakes are off, past a valve and filter? in the servo, it dumps its "exhaust" and lub mist into cam cover/cam box?? will check when I get home.

this could explain the mass of "chuffing" I hear and see ( how=w can you see a chuff? ) when the oil filler cap is off.......will check that as well , wife press brakes and see difference......some may be oil mist from cam area and some may be blow-by, but engine very good on oil ( shell helix on offer in europarts at the time, so got 2 tins ) about 3/4 litre over 5ik miles, engine has two small leaks, rear crank area and turbo oil return pipe...

interestingly I will not use a pug oil filter again as it was loose the last time I checked ( oil light does not go out instantly after a few days ) oil dribble down oil cooler, also suspect iffy anti drain down valve on filter........Unipart one was great and instant oil light out after a few days on standing....

anyway back to topic....

[zx_volcane]

It should make a fair amount tbh

Should try n suck ya skin off like a hoover

Hmmm not always. Generally they do not need huge amounts of vacuum to work effectively. You could probably suck on the pipe and they would work fine.
I would suspect if you have been bending the hose around its split.

can someone pop off a vac hose and tell me please?

my brakes feel pretty under servo'd - be good to rule vac pump out without swapping it over

[mad306man]

I'll be home at 1, so will get out there and pop the hose off to see what I can find

[MrBigMac]

I would love to know what vacuum it should be producing too ?

[mad306man]

Well my vacuum pump was sucking like a Dutch hooker, so I checked the braided rubber hose that joins the pump to the metal line on the bulkhead.

Looked like this.....



Replaced it with some hose I had spare and boom, all good again.

Brakes are all together much better now so must have been leaking for a while [emoji106]

[zx_volcane]

Well my vacuum pump was sucking like a Dutch hooker

Good to know!

[mad306man]

Dutch hooker is probably cheaper than a new vacuum pump to

[MrBigMac]

Mine must be the pump then as it sucks like someone blowing lol

[Poodle]

Thanks for updating, glad you got it fixed.

[mad306man]

I'd advise everyone to check/change that hose.

The braking improvement is colossal

[MrBigMac]

Mine were all good so thinking the problem is the pump