How to: Install power brakes into 1968-1970 Bus (Pic heavy)

[coolerthanelvis]

What about getting some early split bus rims? 15" with wide 5 bolt pattern. Readily available.
_________________
Shawn
SV2s member #420
'68 Westy

"Do or do not, there is no try."
-Silent Bob

[OB Bus]

Won’t work because he has disc brakes from a 72 with the smaller bolt pattern.
_________________
Larry in OB
Stop dead photo links! Post your photos to The Samba Gallery!
69 Westfalia and 2002 Eurovan Camper.

[Hikelite]

[Zed999]

Great thread. I've done this servo addition to half a dozen buses including a 68 with stock drums. I have to say the 68 drum brakes with servo was "better" than the disc/servo ones. Very light pedal with drums as the non-servo drums were excellent to start with. I used the Brazilian servos, as I was also making the beam brackets the fixing holes being different wasn't a problem and the servos are an inch smaller which helps the handbrake cable situation. I also wired the cables together, it didn't take much to clear the servo.

Without a servo, disc brake buses have appalling brakes, it's a wonder that they were sold that way but cheapskate UK is stuffed with them as we have a lot of (originally) 1600 T1 powered buses here and the servo I think was only standard on T4 powered ones.

When I retro fitted both a T4 engine and servo to my 74, I out-witted myself by using an original balance/servo vacuum pipe and hooked it up to one manifold tube each side. Tidy install I thought as I patted myself on the back, but as my carbs are dual barrel drla this played havoc trying to balance them with a 4-way vacuum gauge and would also give a false reading on a snail type gauge. Now it's just plugged into one and the other is an untidy blocked up thing as is the spare end of the balance tube. Doh!

[aeromech]

You don't need to feed the servo vacuum from both sides of the engine. Once started and the vacuum drawn, there isn't much or any flow so the dual carbs aren't affected during driving.
_________________
Lead Mechanic: San Diego Air and Space Museum
Licensed Airframe and Powerplant Mechanic
Licensed Pilot (Single engine Land)
Boeing 727,737-200-300-400,757,767
Airbus A319,320,321
DC9/MD80
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Fokker F28/F100
VW type 1 1962,63,65,69,72
VW Type 2 1971 (3 ea.) 1978, 1969
VW Jetta
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Capable of leaping tall buildings in a single bound

[Zed999]

[aeromech]

[Tcash]

Adding vacuum Nile for brake booster

The best way is to weld on Bung.

[aeromech]

That wall is pretty thin. I hope it holds. I usually have a plug welded to the wall to add some girth for the fitting
_________________
Lead Mechanic: San Diego Air and Space Museum
Licensed Airframe and Powerplant Mechanic
Licensed Pilot (Single engine Land)
Boeing 727,737-200-300-400,757,767
Airbus A319,320,321
DC9/MD80
BAe146
Fokker F28/F100
VW type 1 1962,63,65,69,72
VW Type 2 1971 (3 ea.) 1978, 1969
VW Jetta
VW Passat
Capable of leaping tall buildings in a single bound

[Tcash]

[aeromech]

Just so anyone looking at this wonders.... the plug welded on only needs to be about 3/8 thick
_________________
Lead Mechanic: San Diego Air and Space Museum
Licensed Airframe and Powerplant Mechanic
Licensed Pilot (Single engine Land)
Boeing 727,737-200-300-400,757,767
Airbus A319,320,321
DC9/MD80
BAe146
Fokker F28/F100
VW type 1 1962,63,65,69,72
VW Type 2 1971 (3 ea.) 1978, 1969
VW Jetta
VW Passat
Capable of leaping tall buildings in a single bound

[Tcash]

[aeromech]

Okay, my welder uses a hole saw. Maybe 1 1/2 inches in diameter. He cuts a plug out of plate aluminum maybe 3/8 thick. Then welds it to the wall of the intake manifold. Now that wall is closer to 1/2 inch thick. Drill and tap for 3/8 NPT. Install fitting. Sizes are approximate.
_________________
Lead Mechanic: San Diego Air and Space Museum
Licensed Airframe and Powerplant Mechanic
Licensed Pilot (Single engine Land)
Boeing 727,737-200-300-400,757,767
Airbus A319,320,321
DC9/MD80
BAe146
Fokker F28/F100
VW type 1 1962,63,65,69,72
VW Type 2 1971 (3 ea.) 1978, 1969
VW Jetta
VW Passat
Capable of leaping tall buildings in a single bound

[Tcash]

Then you step up from 3/8" to what like 1/2" to except the 12mm hose?
Thank you
Tcash

[aeromech]

The fitting I use is 3/8NPT on one end and -8 AN on the other. The hose is 15/32” ID so close to -8 that it works with the Parker Pushlok female hose end.
I can provide pics tomorrow if you want Tim.
_________________
Lead Mechanic: San Diego Air and Space Museum
Licensed Airframe and Powerplant Mechanic
Licensed Pilot (Single engine Land)
Boeing 727,737-200-300-400,757,767
Airbus A319,320,321
DC9/MD80
BAe146
Fokker F28/F100
VW type 1 1962,63,65,69,72
VW Type 2 1971 (3 ea.) 1978, 1969
VW Jetta
VW Passat
Capable of leaping tall buildings in a single bound

[aeromech]

Some pictures

This is a fitting added to a stock intake manifold to supply vacuum for a booster

I put a booster in this 1968 DC and added a fitting to the left side manifold

Here's a pic showing the gates vacuum hose (27231) attached to the Parker -8 Push-Lok fitting

https://www.oreillyauto.com/detail/b/gates-3728/pe...31/4330548

This pic shows the bung welded to the thin wall of the Dellorto manifold being tapped for 3/8NPT

_________________
Lead Mechanic: San Diego Air and Space Museum
Licensed Airframe and Powerplant Mechanic
Licensed Pilot (Single engine Land)
Boeing 727,737-200-300-400,757,767
Airbus A319,320,321
DC9/MD80
BAe146
Fokker F28/F100
VW type 1 1962,63,65,69,72
VW Type 2 1971 (3 ea.) 1978, 1969
VW Jetta
VW Passat
Capable of leaping tall buildings in a single bound

[Jade]

Reviving an older thread here. I did my conversion on my '66 bus about 22 years ago using Wolfgang adapters, '75 brakes, and a bracket we fabbed together. The M/C was leaking into the booster so it was time to refresh everything.

The booster I got has a slightly different bolt pattern. It worked out well because it's rectangular instead of square spacing between the studs so easier to get to when the nuts are tightened down. I powder coated as many of the components as I could.

One question I have, what the tube on the booster on the opposite side of where the M/C mounts? A vent? I just pointed it down so water can't collect in there.

_________________
'66 11 window

[busdaddy]

[Jade]

Excellent, thanks. Will put a filter on it.
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'66 11 window

[aeromech]

I’ve used something like this before


https://www.knfilters.com/62-1600rd-l-vent-air-filter-multi-lingual
_________________
Lead Mechanic: San Diego Air and Space Museum
Licensed Airframe and Powerplant Mechanic
Licensed Pilot (Single engine Land)
Boeing 727,737-200-300-400,757,767
Airbus A319,320,321
DC9/MD80
BAe146
Fokker F28/F100
VW type 1 1962,63,65,69,72
VW Type 2 1971 (3 ea.) 1978, 1969
VW Jetta
VW Passat
Capable of leaping tall buildings in a single bound