Left rear cylinder

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72Hardtop
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Location: Seattle, WA./HB. Ca./Shizuoka, Japan
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Left rear cylinder

Post by 72Hardtop » Sat Jul 08, 2017 12:36 am

Noticed the left rear wheel cylinder is slightly leaking (1972 Westy) . Ordered 2 new wheel cylinders. Was glancing over your brake procedure. I hate brake jobs....Wondering how much of a bear it will be to get the axle nut off? (Been awhile....06). I had replaced both of them last in April 2006. I'm guessing not all of your brake rebuild article will apply given I'm not rebuilding my own cylinders. I adjusted the rears not long ago and everything else is in order.

Did I mention I hate brake jobs as well as CV joint jobs?
1972 Westy tintop
2056cc T-4 - 7.8:1 CR
Weber 40mm Duals - 47.5idles, 125mains, F11 tubes, 190 Air corr., 28mm Vents
96mm AA Biral P/C's w/Hastings rings
42x36mm Heads (AMC- Headflow Masters) w/Porsche swivel adjusters
71mm Stroke
Web Cam 73 w/matched Web lifters
S&S 4-1 exhaust w/Walker 17862 quiet-pack
Pertronix SVDA w/Pertronix module & Flamethrower 40K coil (7* initial 28* total @3200+)
NGK BP6ET plugs
002 3 rib trans
Hankook 185R14's

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asiab3
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Re: Left rear cylinder

Post by asiab3 » Sat Jul 08, 2017 9:12 am

Ahhhh have fun! I like Colin's trick for getting axle nuts off when I can't find a cheater pipe, though I've only had to do it once, and with my Harbor Freight 3/4" drive bar, not any nice vintage tools. :)

From here:
http://www.itinerant-air-cooled.com/vie ... hp?t=11737

Image
1969 bus, "Buddy."
145k miles with me.
322k miles on Earth.

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Amskeptic
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Re: Left rear cylinder

Post by Amskeptic » Mon Jul 10, 2017 6:49 am

72Hardtop wrote:
Sat Jul 08, 2017 12:36 am
Noticed the left rear wheel cylinder is slightly leaking (1972 Westy) . Ordered 2 new wheel cylinders. Was glancing over your brake procedure. I hate brake jobs....Wondering how much of a bear it will be to get the axle nut off? (Been awhile....06). I had replaced both of them last in April 2006. I'm guessing not all of your brake rebuild article will apply given I'm not rebuilding my own cylinders. I adjusted the rears not long ago and everything else is in order.

Did I mention I hate brake jobs as well as CV joint jobs?


You don't have to remove the axle nut on post-1970 VW buses. You can pop the composite drum off and sort of work around the remaining hub. Stop hating and get in there and gitterdun.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

72Hardtop
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Location: Seattle, WA./HB. Ca./Shizuoka, Japan
Status: Offline

Re: Left rear cylinder

Post by 72Hardtop » Wed Jul 19, 2017 8:08 pm

Complete...

Removed both drums. Clean everything up real well. Drums looked good as did the shoes. Replaced both wheel cylinders with ATE brand cylinders. Also removed the star adjusters and gave them a one over and applied liberal amount of copper anti seize prior to placement. Once everything was buttoned up closed the stars (till no movement, bled system with Mighty-vac. Backed off the stars until slight drag while turning drum/s. Check pedal movement (great!), re-check rear adjustment. E-brake adjustment was spot on without any need of further adjustment up front.

I replaced all the hoses roughly 5 years ago (German supply). Also replaced both front calipers. Likely going to have to replace the right front one given it will pull to the left when braking. Have confirmed via light taps with no hands on the wheel that it's the front. I'll bleed that one first and re-confirm the pull.
1972 Westy tintop
2056cc T-4 - 7.8:1 CR
Weber 40mm Duals - 47.5idles, 125mains, F11 tubes, 190 Air corr., 28mm Vents
96mm AA Biral P/C's w/Hastings rings
42x36mm Heads (AMC- Headflow Masters) w/Porsche swivel adjusters
71mm Stroke
Web Cam 73 w/matched Web lifters
S&S 4-1 exhaust w/Walker 17862 quiet-pack
Pertronix SVDA w/Pertronix module & Flamethrower 40K coil (7* initial 28* total @3200+)
NGK BP6ET plugs
002 3 rib trans
Hankook 185R14's

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Amskeptic
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Re: Left rear cylinder

Post by Amskeptic » Sat Jul 22, 2017 9:31 am

72Hardtop wrote:
Wed Jul 19, 2017 8:08 pm
Complete...

replaced both front calipers.
Likely going to have to replace the right front one given it will pull to the left when braking.
That could be an extreme solution if the calipers have already been replaced.

Can you get in to the calipers and actually feel the resistance of the pistons to retraction force with a pry bar?
You should find a resistant piston over on the right caliper.

Also:
Tire pressures?
Hot right rear drum from slightly tight adjustment?
Apply the ebrake at 30 after brakes are good and warm just to see if it affects direction.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

72Hardtop
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Location: Seattle, WA./HB. Ca./Shizuoka, Japan
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Re: Left rear cylinder

Post by 72Hardtop » Sat Jul 22, 2017 12:01 pm

Amskeptic wrote:
Sat Jul 22, 2017 9:31 am
72Hardtop wrote:
Wed Jul 19, 2017 8:08 pm
Complete...

replaced both front calipers.
Likely going to have to replace the right front one given it will pull to the left when braking.
That could be an extreme solution if the calipers have already been replaced.

Can you get in to the calipers and actually feel the resistance of the pistons to retraction force with a pry bar?
You should find a resistant piston over on the right caliper.

Also:
Tire pressures?
Hot right rear drum from slightly tight adjustment?
Apply the ebrake at 30 after brakes are good and warm just to see if it affects direction.
Colin
Haven't popped the right front brake off yet. What I do know and have confirmed is....

1. Tire pressures are good 30psi front and 36psi rears

2. Rear drums temps are equal after a good run.

3. Application of ebrake brings bus to straight stop as well.

Will pull the right front wheel off and have a look at the pads. Will also bleed that caliper as well. But I'm leaning at this point to a sticky caliper. The front end is solid did complete front end rebuild back in 2012.

Image
1972 Westy tintop
2056cc T-4 - 7.8:1 CR
Weber 40mm Duals - 47.5idles, 125mains, F11 tubes, 190 Air corr., 28mm Vents
96mm AA Biral P/C's w/Hastings rings
42x36mm Heads (AMC- Headflow Masters) w/Porsche swivel adjusters
71mm Stroke
Web Cam 73 w/matched Web lifters
S&S 4-1 exhaust w/Walker 17862 quiet-pack
Pertronix SVDA w/Pertronix module & Flamethrower 40K coil (7* initial 28* total @3200+)
NGK BP6ET plugs
002 3 rib trans
Hankook 185R14's

72Hardtop
Old School!
Location: Seattle, WA./HB. Ca./Shizuoka, Japan
Status: Offline

Re: Left rear cylinder

Post by 72Hardtop » Sat Jul 22, 2017 3:43 pm

Update:

Removed the right front pads and found them to be in perfect condition with 50% or so pad on both (equally). Was able to push both calipers back even with the caliper seals. Clean everything up and put back together. Rotor looked great (both sides).

Took for a drive and it will still pull left with moderate to heavy braking. Checked the rear brakes (drums) and neither are any different in terms of temps compared to one another after a bit of driving. Pulling the ebrake will bring the bus to a stop with no discernible pull either way. All the rubber hoses were replaced back in 2012 (purchased from German Supply).

Only thing I can think of at this point would be to bleed the right front brake and test drive again. But I can't imagine that a bleed issue could be the answer. I see you mentioned the right rear drum possibly over adjusted? You meant left (bus pulls left)? I confirmed both are adjusted on par with one another no discernible difference in temps after a run and ebrake shows good stop with no pull issue.
1972 Westy tintop
2056cc T-4 - 7.8:1 CR
Weber 40mm Duals - 47.5idles, 125mains, F11 tubes, 190 Air corr., 28mm Vents
96mm AA Biral P/C's w/Hastings rings
42x36mm Heads (AMC- Headflow Masters) w/Porsche swivel adjusters
71mm Stroke
Web Cam 73 w/matched Web lifters
S&S 4-1 exhaust w/Walker 17862 quiet-pack
Pertronix SVDA w/Pertronix module & Flamethrower 40K coil (7* initial 28* total @3200+)
NGK BP6ET plugs
002 3 rib trans
Hankook 185R14's

72Hardtop
Old School!
Location: Seattle, WA./HB. Ca./Shizuoka, Japan
Status: Offline

Re: Left rear cylinder

Post by 72Hardtop » Sun Dec 30, 2018 3:05 pm

This issue after replacing the booster and master cylinder has completely vanished.
1972 Westy tintop
2056cc T-4 - 7.8:1 CR
Weber 40mm Duals - 47.5idles, 125mains, F11 tubes, 190 Air corr., 28mm Vents
96mm AA Biral P/C's w/Hastings rings
42x36mm Heads (AMC- Headflow Masters) w/Porsche swivel adjusters
71mm Stroke
Web Cam 73 w/matched Web lifters
S&S 4-1 exhaust w/Walker 17862 quiet-pack
Pertronix SVDA w/Pertronix module & Flamethrower 40K coil (7* initial 28* total @3200+)
NGK BP6ET plugs
002 3 rib trans
Hankook 185R14's

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Amskeptic
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Re: Left rear cylinder

Post by Amskeptic » Mon Dec 31, 2018 7:23 am

72Hardtop wrote:
Sun Dec 30, 2018 3:05 pm
This issue after replacing the booster and master cylinder has completely vanished.

The pulling left went away with a master cylinder replacement?

This is "odd".

Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

72Hardtop
Old School!
Location: Seattle, WA./HB. Ca./Shizuoka, Japan
Status: Offline

Re: Left rear cylinder

Post by 72Hardtop » Fri Jan 11, 2019 4:03 pm

Amskeptic wrote:
Mon Dec 31, 2018 7:23 am
72Hardtop wrote:
Sun Dec 30, 2018 3:05 pm
This issue after replacing the booster and master cylinder has completely vanished.

The pulling left went away with a master cylinder replacement?

This is "odd".

Colin
Yep....gone.

Best guess. The MC was behaving in a way that was limiting 'ideal' pressure to one side vs another (slight leakage). Given a dual circuit system the pulling could be more pronounced depending on which circuit it affects mostly (front vs rear).
1972 Westy tintop
2056cc T-4 - 7.8:1 CR
Weber 40mm Duals - 47.5idles, 125mains, F11 tubes, 190 Air corr., 28mm Vents
96mm AA Biral P/C's w/Hastings rings
42x36mm Heads (AMC- Headflow Masters) w/Porsche swivel adjusters
71mm Stroke
Web Cam 73 w/matched Web lifters
S&S 4-1 exhaust w/Walker 17862 quiet-pack
Pertronix SVDA w/Pertronix module & Flamethrower 40K coil (7* initial 28* total @3200+)
NGK BP6ET plugs
002 3 rib trans
Hankook 185R14's

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