Vacuum Brake Servo

[Pirvu Eugen]

That error is given by that sensor, the brake fluid level sensor or the hydraulic oil level sensor.
Check those switches too.....maibe one of them is not connected or not in closed contact position.
Hope this helps!

[Biturbo]

short the 2 wires from the old pressure sensor at the old servo.

I did that but same.Still sing on screen

[Pirvu Eugen]

short the 2 wires from the old pressure sensor at the old servo.

[Biturbo]

Any one sorted problem with speedo computer after converting to vacuum servo?It's show and blink red exclamation mark.

[Pat D]

I managed to get the grinder in my freshly painted engine bay and cut the brackets out. I used a dremel to do the cuts and an angle grinder to smooth it all out. There is also another little bracket in the curved section of the strut & from memory holds a fuel line rubber mount that needs to be cut out as well.

I placed it in position and it fits perfectly, the linkage to the pedal seems spot on.
The S2 master cylinder bolts straight on to the vacuum servo and will look like it should also work fine. I measured the length of the linkage shaft on both master cylinders and they were very much the same, a couple mm difference was all that I could see.

Gave the servo a birthday, then etch primed & epoxy coated the bare metal in the engine bay. I'll fit it all in once it dries and then see if I should weld an alternative strut to firewall bracket in there.

Some pics in the process:

[Error404]

That's what I'm going to do, if you ask Vas I'm sure he'll post up a pic of his which has a curve in it to go around the vacuum servo.

Edit : You can see it in this post here, LHD, but you get the idea.

http://www.s2forum.com/forum/showpos...&postcount=482

I think Pat means the little horizontal web brackets between the strut tower and the firewall. Vas is using a bigger servo on the LHD than we can use on the RHD, due to the strut turret not having enough clearance - i don't think there is an issue with the strut brace on the RHD using the vac servo

[Tonks4x4]

There are several types of servos and there is a number of different spacer adapters that can be fitted to the rear of the servo where it bolts to the bulkhead.
Along with this there is several lengths of push rod lengths from servo to pedal.
So be prepared to do some cutting and welding if you want to use a different spacer width to give you more clearance in the engine bay.

The standard S2 master cylinder can be used on all the different types of servo.
However a spacer rod needs to be machined for the inside of the master cylinder where it locates onto the pin inside the servo.

Then the easiest way to cure the pump problem is remove the front set of pistons as already mentioned earlier in the post.

Then wait to do the power steering mod at a later stage when someone has a good working setup that works well.

[Pat D]

Great, well I'll stick with the original plan and use an electric PAS pump and vacuum brakes. I'll cut the strut bracket out tomorrow.

I just removed the vacuum servo from my B4 and emptied out a good half litre of brake fluid, so I filled it up with degreaser and then hosed it out. Should hopefully still be ok.

[AndyP]

I'm wondering how much support that strut bracket provides and if it's worth fabricating another one around the vacuum servo.

That's what I'm going to do, if you ask Vas I'm sure he'll post up a pic of his which has a curve in it to go around the vacuum servo.

Edit : You can see it in this post here, LHD, but you get the idea.

http://www.s2forum.com/forum/showpost.php?p=691299&postcount=482

[Error404]

Haha, that's what i was trying to avoid

I'm wondering how much support that strut bracket provides and if it's worth fabricating another one around the vacuum servo.

Not a massive amount, its just a pressed piece of sheet, i bet you could bend it in your hands with it off the car

[Pat D]

like this

http://www.ebay.co.uk/itm/JAGUAR-XJ6...item2a27474a48

That looks like another idea, I guess I could use one of them as well for the brakes

[Pat D]

So I would just cut that strut bracket and make your life easier

Haha, that's what i was trying to avoid

I'm wondering how much support that strut bracket provides and if it's worth fabricating another one around the vacuum servo.

[driftin jo]

like this

http://www.ebay.co.uk/itm/JAGUAR-XJ6...item2a27474a48

[driftin jo]

I have few questions in regards to the brake bomb and high pressure lines, hopefully someone might know the answers.

1. Is the high pressure line from the PAS pump to the steering rack a different pressure to the one going to the bomb? Hence two separate pump outputs?

2. Can the bomb be deleted all together if there is no need for assist in the event of the engine not running and just run the high pressure line direct to the master cylinder?

Reason I ask is that I would like to use an electric PAS pump without Vacuum servo brake assist, since the electric pump can run with the engine off there is no need for accumulated assist.

Yes they are two different pressures, the PAS line is much lower pressure.

No, you cant run the pump line straight to the servo, a couple of quick taps of the brake and you would have less pressure as the pump is not be able to keep up, that's why you have an accumulator, it's not just in case the engine stalls or the belt snaps.
You will find that even cars that use electric pumps have an accumulator, usually as part of the pump assembly, I looked at fitting one once, I think it was off a jag.

[Error404]

Hey Pat:

An electric PAS pump won't offer you brake assist aswell. You would still need to retain the dual stage PAS pump, making the electric PAS pump kinda pointless. That is why people switch to electric PAS pump and vacuum servo at the same time. Or just vacuum servo and use a single stage hydro PAS pump as per the factory setup

The bomb works off the front section of the dual pump, using pistons driven by an elliptical collar, which AFAIK is higher pressure but I assume much lower flow than the steering side (the brake assist consumes very little fluid by volume compared to the rack)
The steering circuit is about [100bar].

As well as an accumulator, the bomb acts as a pressure damper for the servo, without the bomb i think you would need to use something to smooth the pump output, otherwise you will feel the pump through the brake pedal and it wont be very pleasant (feels like the ABS is on continually)

So I would just cut that strut bracket and make your life easier

HTH & Merry Christmas