Date: Fri, 2 Sep 2022 15:46:50 +0000
Reply-To: Richard Koerner <rjkinpb@SBCGLOBAL.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Richard Koerner <rjkinpb@SBCGLOBAL.NET>
Subject: Re: Happy Friday, Rear brake adjustment.
In-Reply-To: <BL0PR05MB49160E70D3BF505560DD85B5A07A9@BL0PR05MB4916.namprd05.prod.outlook.com>
Content-Type: text/plain; charset=UTF-8
Excellent comments and pictures...as usual...and I trust your experience and expertise.
Here's the thing: I've owned my '85 Tintop for 33 years. I've pulled on the Parking Brake lever countless times. Yes, it always feels about the same; first a significant gap, and then always 3 or 4 clicks to end of travel. I would certainly have noticed if there were 6 or 8 clicks (like in my Toyota Highlander). Is it possible that pre-85 Vanagons were set up for 4 clicks of handbrake, and that later Vanagons were designed with a lever that provided 8 clicks? Finer resolution? Your previous comment about "drag" at about notch #4 and then full lock at notch #8 caught my attention; after my adjustment to yoke nut, I get slight drag at notch #2, significant holding power at notch #3, and total lock at notch #4. So actually this corresponds to your recommendations....only things are different by 1/2.
I don't have a floor jack or jackstands to take drum off and inspect; I am mostly a driver. My garage is tiny.
Still....I can't have Vanagon "sliding" off parking brake, no matter how hard I tug. Which was previous situation before I adjusted the yoke nut.
Can any other List members report? State year of Vanagon, and how many clicks you have between limp and fully locked? Honestly, I have never driven another Vanagon of any year, so no experience, and not nearly the same expertise and wisdom as Dennis.
On Friday, September 2, 2022 at 07:12:22 AM PDT, Dennis Haynes <d23haynes57@hotmail.com> wrote:
Here is a link for some pictures that maybe helpful.
https://1drv.ms/u/s!AqaEiIhKCAKbiJIYx-ZxNT_kclWRdg?e=3DA35dub
When it comes to brakes the Vanagon gets some poor press for the brake desi=
gn, and the choice that they still used drum brakes in the rear. Yes some o=
f that decision was likely based on cost, except for the self-adjusters the=
se brakes are carryovers from the bay windows. Still while most modern cars=
have disk brakes, drum brakes are still the usual choice for trucks and bu=
sses. Drum brakes simply offer more surface area for friction and heat diss=
ipation. Disc rely more on physics and clamping forces. Discs are also more=
consistent, weather resistant, and give better pedal feel of mechanical-hy=
draulic systems.
That said a downside of drum brake systems is that they are somewhat mainte=
nance intensive and set-up adjustment, and fitting of parts is critical. Th=
e Vanagon adds a bit with the design of the handbrake system, the finicky n=
ess of the adjustment system, the closed drum-backing plate, and the lack o=
f proper parts, especially the shoes for service.
Getting to the maintenance side of this, many like to think that we can do =
a brake job and it should last for some long period of time. With the drum =
brake set up there are number of maintenance items that often will not last=
the life of the shoes. Thanks to the composite drum design, (drum separate=
s from flange), service and inspection is actually quite easy. Unless the s=
hoes are deeply worn into the drum or this is a major rust ridge on the dru=
ms behind the shoes, or on the drive flange, the drums are easily removed a=
nytime the wheel is removed. No need to remove the axle nut. Once the 2 ass=
embly screws are removed, the drum can usually be popped off hitting the ed=
ge with a dead blow hammer. If needed the adjusters can be backed off to al=
low the shoes to clear the ridge. If really difficult to remove service has=
been neglected way to long.
With the drum off you want to do an inspection. . With the closed design th=
e drum will usually be filled with brake dust. You want clean this out as t=
hat dust churning in there is not good. Check the condition-straightness of=
the backing plate. Look for signs of wheel bearing grease and brake cylind=
er leakage, check the wear pattern on the shoes, look for signs of heat che=
cking, glazing, cracking, and separation of the lining from the shoe. This =
is more common with vans that sit outside as the shoe starts to rust, the r=
ust will jack the lining off the shoe causing the bond to fail. BTW this al=
so happens with disc pads. Back to the cylinders, check again that you have=
the correct ones with the internal spring to prevent the pistons from suck=
ing back.
Then you want to check the hand brake and adjuster parts. Check that the le=
ver moves freely, along with the cables. It is common for the cable sheaths=
to fail internally causing the cable to bind, not allowing the levers on t=
he shoes to fully return. Check that the levers move freely, not rusted in =
place, and the adjuster screw can turn freely. Lubricate with liquid graphi=
te or other favorite light lubricant. Avoid grease or never seize.
Now for the handbrake adjustment. The only way to properly adjust the handb=
rake is for the drums to be removed so you can see the lever position again=
st the push-adjuster rod assembly. To make this a little easier remove the =
spring that lifts the adjuster lever. This takes that push off the adjuster=
rod. For a new shoe install, adjust the rod to take up all the slack betwe=
en the shoes. Then you want to adjust the brake cables to just touch the ad=
juster rod. Check that both sides are the same. Again this is the only way =
to adjust the handbrake. Same if a follow up adjustment is needed for cable=
sheath or sheath collapse. Then place the spring back on the adjuster leve=
r. With care the adjuster can be tested by carefully using the brake pedal =
to push out the shoes. As the shoes move out the adjuster lever will turn t=
he adjuster nut, when release the lever will drop and then be able to grab =
the next tooth on the adjuster nut. For this to work, again the handbrake l=
ever cannot be putting any pressure on the adjuster-push rod.
With the drums back on pump the brakes a few times to center the shoes. For=
a new install you can usually hear the adjusters click as you operate the =
brakes with the pedal. For new shoes I will manually adjust the brake adjus=
ter to give a very light rub. This gets the shoes seated. For used you want=
some clearance and should able able to turn the rums with no drag at all.
For inspection frequency, the rear should be checked after any known abusiv=
e brake event, when tires are removed for rotation 5-7K miles) and at least=
once/year for little used vehicles.
Hope this helps!
Dennis
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