My 84 rusty project

[boatbuilder]

This evening I took out the old brake booster and the whole pedal assembly. So I can confirm that it is possible to do this without taking the dash out.
First I removed the instrument cluster, air pipes and the two metal dash brackets. I had already replaced the conical head bolts with normal hex head ones so that was easy.
Then I sucked the brake fluid out of the reservoir with a little hand crank fuel pump I use for model airplane fuel.
Then I disconnected and plugged the two brake lines on the master cylinder (11mm) and the one on the clutch master cylinder (12mm). Then disconnected and plugged the rubber feed pipe for the clutch cylinder.
Then just undid the two 13mm nuts and removed the brake master cylinder along with the reservoir.
This is what it looked like at that stage.



Then I removed the four 13mm bolts holding the aluminium pedal frame to the van and the whole unit can then be pulled upwards. Then I took out the split pin and clevis pin at the back of the booster and unscrewed the four nuts holding it on and the booster was off.





At this stage I tried to pull out the rest of the unit but it just won't fit up through that gap....the pedals are too wide. So I removed the clutch pedal. Simply a matter of removing the split pin and clevis pin, unhooking the clutch pedal return spring and then removing the e clip from the large pin, tapping the pin inwards until the clutch pedal comes off.





Then the rest will come up and out leaving you with this...



It looks like everything has been leaking for a long time. The old booster was saturated with brake fluid inside and both master cylinders were leaking.

Here are the VW and BMW units side by side...bit of a size difference.



The clevis off the old booster will be tapped to match the threads on the bmw one and adjusted to the same length as the old unit. The old unit measures 114mm from the back of the booster to the centre of the clevis hole although I will adjust the new one to 111.5mm as per the Bentley manual.

[boatbuilder]

I grit blasted the bmw brake servo this evening. Ran a bead of sealant around the join in the unit...can't do any harm. It'll get a couple of brushed coats of epoxy primer. Not worth dirtying the spray gun!

[boatbuilder]

So here are the two boosters side by side. The vw clevis needs to be tapped to match the threads of the bmw unit. That's m10x1.5





Then you have to cut about 10mm off the rod on the bmw booster. The distance from the back of the booster to the clevis hole is 111.5mm.



I used two steel rulers to get the correct measurement and put some threadlock on the rod to keep it in position.



The pedals look a bit better after a good decreasing...





Then it's a matter of bolting the booster back on...



The bigger booster hits off the blower housing so needs the lip trimmed off with a hacksaw...





All back in place and it looks like I'll have to trim a bit off the top edge of the reservoir to leave some clearance at the back of the dash clocks.



Unfortunately it looks like the diaphragm in the bmw servo is gone as it's not giving any boost. So I took it out and it's going back to the breakers tomorrow and hopefully I'll get a working one this time!

[boatbuilder]

Until the new brake booster turns up, I've gone back to the insulation and carpet lining.

More foam and bubble foil glued to the roof. The self adhesive backing is pretty rubbish so I used Trimfix high temp spray glue to secure it to the roof.
I glued some strips of foam into the recesses in the roof and then put one big sheet over it so the overall effect is flat-ish.









The plan is to glue the stretch carpet to the bubble foil - most people seem to use plywood panels but I thought I'd try this instead.
There is probably a good reason why people don't do it this way that I can't think of at the moment, but I'll find out this evening!
The roll of carpet is about 2 metres wide so I'm hoping to be able to do the whole roof in one piece.

[SamsBus2012]

I did the underside of my hightop with a single piece. I found the best way to do it was to first stick the carpet along the centre-line from front to back over a fairly narrow strip then worked each side out a bit at a time which avoided any creases and the need to pull off and start again - case of less is more. Admittedly a bit easier on the hightop as not so many cross-members to deal with as you will. Have to say through, the stretchiness makes it really easy to shape. I did mine as a bit of a rush job without insulation and regret it now. It will be interesting to see how well your sticks.

[boatbuilder]

Thanks, what I'm slightly worried about is that if I have to pull the carpet off to reposition it, the bubble foil will come with it!

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[SamsBus2012]

Exactly. The adhesive has quite a powerful grab. I found that after I fixed along the centre line (which was done from the middle third first then the two ends if that makes sense) I could then just work a small section at a time to avoid too much out of position sticking. Again, the sides were done from the middle first then working my way toward back and front a section at a time. The carpets pretty forgiving to be honest but I take your point about the bubble insulation.

[NicBeeee]

[quote="boatbuilder"

The plan is to glue the stretch carpet to the bubble foil - most people seem to use plywood panels but I thought I'd try this instead.
There is probably a good reason why people don't do it this way that I can't think of at the moment, but I'll find out this evening!
The roll of carpet is about 2 metres wide so I'm hoping to be able to do the whole roof in one piece.[/quote]

I have done the same, its been on for a couple of years, only difference is that I used vehicle foam backed roof lining to finish for a little extra insulation and to give a contrast to the grey stretch lining on the sides. I like the way it still shows the shape of the roof and so far has had great insulating properties both with keeping the heat in and out. I put the roof lining up in two pieces one section for the cab and the other for the rest of the roof.

The way I did it was to draw a line on the back of the carpet right down the middle and a line with a marker pen down the middle of the roof. Sprayed some glue to the front section and slowly worked my way back, I was able to keep the lining central by making sure the two lines met.

[boatbuilder]

So the roof has now been carpeted and I'm very happy with how it looks. I started by making sure I had a crisp straight cut edge at the front and gluing it the whole way along the front edge. Then worked my way backwards in the middle, gluing a bit at a time. Then glue it out to the sides.
One piece of carpet did the whole roof and down the sides about half way. It's pretty cool how the carpet stretches when you need it to.
A pack of one sided razor blades is great for cutting and trimming the carpet. And the high temp spray glue is great. I must have used about 10 cans of it at this stage.

[Smcknighty]

What did you do with the edge around the window out of interest? Looks good


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[boatbuilder]

Its a panel van so it has the double skin around the windows. I just cut it along the edge of the metal and might cover the gap with a rubber seal at some point.

[boatbuilder]

One sided razor blades are great for trimming the headliner...



Doing a join...







A bit of headscratching involved on how to handle the fibreglass window surround and the panel below...



BMW Brake Booster Number two - this one looks a lot fresher than the first one. I sanded the rusted areas and gave it two coats of POR15 paint.





Here it is in position - Three mods required to get it to fit.
You have to cut about 3mm off the lip on the corner of the blower housing to clear the side of the booster.
Then you have to bend out the right hand metal dash strut a few millimetres (not much just maybe 3 or 4mm) to clear the metal brake line.
And to clear the back of the dash clocks, I sanded a bit off the front of the reservoir.

[Titus A Duxass]

I think you should separate the BMW servo parts and get them into the WiKi.
It is a very good guide with excellent fotos.

[bigbadbob76]

I've just spent several hours of works time reading through this thread.
Great stuff BB and a credit to your hard work.
I thought I had a big job on until I saw yours so you've given me a lot of inspiration and hints and tips and how-to's for pretty much everything I have to do.
Many thanks and we're hoping to take our rust heap over to your fair island next summer if I don't take 5 years to do it, haha.

[boatbuilder]

Thanks for the comments... I don't really know how to use the wiki so maybe someone could do that!

Some work done on the floor. I used half inch wbp plywood, sealed with yacht varnish both sides and edges. I used a strip of 6mm marine ply along the edge of the door, stuck with tigerseal, to make it level. Then I put down some 3mm rubber underlay and then the plywood on top. I used carriage bolts to bolt it all down. I marked the positions of the corrugations on the top of the plywood for future reference in case I need to attach anything at a later date.