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Thu Jun 17, 2010 6:46 am

bigbore wrote: The port closest to the booster is for the rear brakes. are you going to relocate the reservoir behind the seat? and then there is the vent to install. Not to be nit picking but I don't see a rubber boot on the clutch cable tube. I mention it becouse I just got done putting them on my bus today.

Thanks BB, so the port furthest forward actually is for the rear circuit? Ok. I don't see any reason to relocate the reservoir. It looks to me like a 3 ft. piece of 1/2" ID brake hose will do the trick. I haven't been able to work out the vent line yet. One thing, the port for the vent will have to be clocked more at 9 o'clock as opposed to 12 because of clearancing issues. I believe as long as I can keep water and dirt out of it there shouldn't be any problem. Also, as you pointed out BB the rubber boot is missing on the clutch cable tube. It's a detail that might be left for a future date.

Thu Jun 17, 2010 11:35 am

Those little boots are a pain to install on the clutch cable let me tell you. :?

Mon Jun 21, 2010 1:41 pm

Ok, here's an update on the booster installation. So far doing the mechanical installation has been fairly easy.

Once the booster was mounted with the mc I began installing the hard lines. I was able to buy a T fitting from my local VW part supplier and a pre-made hard brake line about 2 feet long. I took the two front lines and connected them into the T and the new brake line which I ran back to the mc.

I ran the vacuum line to the drivers side intake manifold (dual dellortos)

and then up to the booster. I cut the rear hard line to remove excess tubing. It was long because I had moved the mc from in front of the beam to behind the beam. Then I used a 3/16 swagelock union and connected a piece of pre-made hard line to the shortened existing rear circuit line. This original brake line is 4.75mm which is the same as 3/16.

The original reservoir was left in place on the front drivers kick panel and I ran some line from it straight into the new mc reservoir.

The pic shows the two switches on the mc but I replaced them with three pole switches. Right now I'm trying to get the wiring figured out so that my warning circuit works as well as the brake lights.

Mon Jun 21, 2010 2:28 pm

Looking real good. You've been busy. We're all waiting to hear how it works on the road. I was a little curious about your pedal to booster linkage. Is the pedal pivot, spring, and pivot mounting on a '68 the same arrangement as my '71? I know you lengthened the connecting rod to make up for the difference in distance.
A comment would be to be sure you get a real good filtered breather line for the booster. Yours wouldn't have the special line and compartment in the dog leg like ours.
two questions- The fluid line to the res. looks like simple rubber hose. Is it some kind of brake fluid compatable hose?
The other is regarding the vac line to the one manifold. Evidently Dell's don't use a balance line between both sides like the single barrel carbs and so you can't easily draw off both sides. Are you concerned with difference in engine running when only one side gets a drop in manifold vacuum? And were you able to get a large enough connection to that one manifold? My baby Webers use a balance line so the booster feeds off of both manifolds.

When is the big test?

Mon Jun 21, 2010 3:28 pm

" Is the pedal pivot, spring, and pivot mounting on a '68 the same arrangement as my '71? I know you lengthened the connecting rod to make up for the difference in distance."

It was a real simple matter of removing the old mc and installing the newly lengthened rod. It fit almost perfectly. Actually DBM, I was reading my BENTLEY today (believe it or not) and it got me thinking about the clearance needed for the rod to mc (ref. 1968-1970). The booster needs a similar clearance and I need to check on that.

"get a real good filtered breather line for the booster"

Yes, I know. Another detail but important. Any suggestions?

"two questions- The fluid line to the res. looks like simple rubber hose. Is it some kind of brake fluid compatible hose?"

When I bought the gates vacuum hose at Carquest I asked them about hose that was brake fluid compatible. All he could come up with was hose that was transmission fluid compatible. What I decided to do was use a left over piece of the gates vacuum hose believing that since this was made for brake boosters they probably made it resistant to brake fluid.

"Are you concerned with difference in engine running when only one side gets a drop in manifold vacuum? And were you able to get a large enough connection to that one manifold?"

Well, no and maybe. I'm thinking that once the vacuum is drawn it should stay static as long as there aren't any leaks in the system. The connection is a -8AN hose fitting and is very close to original size. Hopefully I will be doing a driving test soon as soon as I can get the electrical all figured out.

Mon Jun 21, 2010 10:41 pm

Please check with Gates on the compatability. I'd check but rushed for time. Going to vacate for about a week and busy packing.
I'd think that it is a low posibility of being compatable. Very few materials are. Petroleum based fluids and brake fluid require different materials. Samba people have had problems with that before. You wouldn't want to contaminate your system with melted rubber. The only charts I have around here are for seals.
There are some nice little offroad type air filters folks use for case breathers. Chirco might show them in their cat. or site.

Tue Jun 22, 2010 12:23 am

"get a real good filtered breather line for the booster"

Oops, timely reminder for me here too. The original on mine had a hard line that was plumbed into the void between the driver's side outer step and the wheel arch. Right in thinking if I put one back there that there should be no need for a filter?

Tue Jun 22, 2010 8:30 am

Desertbusman wrote: Please check with Gates on the compatability. I'd check but rushed for time. Going to vacate for about a week and busy packing.
I'd think that it is a low posibility of being compatable. Very few materials are. Petroleum based fluids and brake fluid require different materials. Samba people have had problems with that before. You wouldn't want to contaminate your system with melted rubber. The only charts I have around here are for seals.
There are some nice little offroad type air filters folks use for case breathers. Chirco might show them in their cat. or site.

I'll try to check with Gates on the hose. Those filters are called K&N I think. Have a nice vacation. Thanks for the advice.

Thu Dec 23, 2010 10:42 am

Curious how this worked? I am swapping out my 71 beam for a link pin beam and i am concerned about the brake booster set up. I am debating on adding a plate to the lp beam and keeping everything as is. Or, tearing everything out and installing an early bay MC. From the looks of things, it would be easier to just mount the booster to the new beam.

Any opinions or guidance?

Thu Dec 23, 2010 10:51 am

Have not a clue what this whole big thread is about. Putting a booster on drum brakes? All that work. In a bus that old one would think you could just drag your feet... :lol:

Thu Dec 23, 2010 11:02 am

I agree with adding a booster...but since mine is already there just curious if I should leave it and reattach everything? Or, just remove it and go with an earlier set-up.

Thu Dec 23, 2010 11:35 am

68moose wrote: Curious how this worked? I am swapping out my 71 beam for a link pin beam and i am concerned about the brake booster set up. I am debating on adding a plate to the lp beam and keeping everything as is. Or, tearing everything out and installing an early bay MC. From the looks of things, it would be easier to just mount the booster to the new beam.

Any opinions or guidance?

You don't say what year bus you have but I assume it's a 1971. You want to install an old link pin style beam for some reason not stated. I don't think they are interchangable.

If you can actually mount a non-booster beam and you still want to have power brakes then you should fabricate a plate to have welded in place like this

The bus has been on the road with a high performance engine for a few months now. I've had a couple different experienced bus drivers give me their opinions of it and each one liked it a bunch. Even though it has 4 wheel drums, the booster helps significantly and takes a load off the drivers foot.

Thu Dec 23, 2010 12:55 pm

Yes, its a 71. I am swapping out to a linkpin beam to lower it and go to wide five bolt pattern. It will bolt up no problem with the new sideplates that have both split and bay bolt patterns. Everything is bolt on so it can all be swapped back later. It looks like the best way to go is to just add a plate to the new beam and go with power assisted drum brakes.

Thanks for the information and detailed pictures.

Mon Sep 05, 2011 9:41 pm

I've got all the stuff coming to put disc brakes on my 68 bus, and convert it to 5*112, and now I worry it will be harder to stop than ever since I won't have a booster? Anyone put disc brakes on a bus without a booster have any comments they want to share about the experience?

Tue Sep 06, 2011 6:20 am

I've driven buses with stock brakes, disc in front and drums in the rear, when the booster wasn't working. I can tell you that the power assisted DRUM brakes all around on this 1968 bus I've been working on work great. I don't see the need to do the disc conversion and having the wide five wheels keeps the original look. Get yourself one of these

and one of these