[T2] 1971 Bus brakes

[Richard F Coombs]

Hello, Jim,



Have you ordered new master cylinder grommets already? If not, you should also order sealing sleeves for the tube connecting the upper & lower reservoirs. At some point, while you're doing all this, those sleeves will tear, & you'll have another leak (AMHIK).



The Type 2 tech library has a good write-up on the master cylinder reservoir here: http://type2.com/rvanness/mastres.htm  It includes part numbers for both the master cylinder grommets & the sealing sleeves. When I got mine I ordered extra ones for spares, since they're not that expensive.



A small leak at the lower reservoir shouldn't affect brake function as long as the upper reservoir is kept topped up. The master cylinder will be fine as long as it's kept topped up, so you can continue to work on the system.



I wouldn't give up & take it to a mechanic just yet. Since you've replaced the master cylinder, it's likely that you still have some air in the system. I would start by bleeding the master cylinder at the lines, by cracking the fittings just a bit, & using them as a bleed valve.



Then, I would do the same with both lines at the proportioning valve.



Moving on, I would bleed the calipers before moving to the rear wheels. Make sure to keep topping off the brake fluid, so the master cylinder never gets a chance to suck air.



At the rear, give the cylinders a good bleed to make sure they're free of air, then check your brake adjustment. The gap between the shoes & the drums has a big influence on pedal height, especially on a manually adjusting system. I usually start by tightening the adjuster on the primary (rear facing) shoe until I can't move the wheel by hand, then loosening the adjuster three notches on the star wheel. I do the same for the front facing (secondary) shoe, & then check to see what I've got.



The adjustment is right when you can turn the wheel by hand with just a bit of resistance. You'll likely feel a "tight" spot, but that's OK as long as it isn't extreme. You want the shoes as close to the drums as they can get without binding. Adjust both rear wheels this way, & if you've been living right, & the planets are properly aligned, you should have a consistent hard pedal. It will be quite hard with the engine off, since the bake servo isn't under vacuum.



To test the servo, put your foot on the brake, & start the engine. Your foot should sink a little, but the pedal should stay firm at that lower level. If there is no change, or the engine idle changes, or you hear whooshing & gurgling sounds, you likely have servo, servo vacuum line, or check valve issues.



Don't give up! On the last Bus I bought, I had to go over the entire brake system to correct errors the PO's "mechanic" had made. Lots of new parts, all installed incorrectly, & a leaking rear wheel cylinder that was mysteriously overlooked.



You are most likely the best mechanic for your antique VW!



BTW, congratulations on choosing a '71 Bus. '71's ROCK!



Richard

'71 hippie Bus "Putt-Putt"
'71 Greatful Dead Bus "Sugar Magnolia"
my71vwbusputt-putt at blogspot.com












1.           I have been working on my brakes lately.  New shoes, pads, turned rotors, drums, new master cylinder, flex hoses front & rear.  Bus Depot did not send new grommets for the reservoir to master cylinder so I asked for new because mine were squishy.  Now I have a leak at the juncture of rear reservoir and master cylinder.  Also, brakes are about like they were before I started.

2.           Does anyone know of a bus mechanic near Charleston, SC?  I am ready to turn it over to a mechanic.

3.           Many thanks.





Jim