Date: Tue, 20 Mar 2012 11:29:49 -0700
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: Rear Brake set up-The spacers
In-Reply-To: <B2F3BBBE-548D-4EC5-AE22-D9AA10F10F42@gmail.com>
Content-Type: text/plain; charset=windows-1252; format=flowed
One additional thing I would add...
always do only one side at a time !!
that way ...you can go look at the other side when you wonder which way
something fits.
scott
turbovans
On 3/20/2012 6:36 AM, Finn Runyon wrote:
> Dear Dennis,
> As always, immensely helpful. Can't thank you enough! Looks like we will be heading to the Grand Canyon at the end of the week after all…
> Best,
> Finn
> On Mar 19, 2012, at 7:09 PM, Dennis Haynes wrote:
>
>> VW did not always use self-adjusting drum brakes. On the non-self-adjusting
>> versions the lower shoe rests were the adjusters. There was a star wheel,
>> (nut) (113609205) and the slotted post (pin) (211609279) and two holes in
>> the backing plate that allowed you to reach in with a screwdriver to make
>> adjustments. This was regular maintenance. So as the shoes wore the bottoms
>> were adjusted out to compensate so with regular care the entire shoe was
>> worn and the entire friction surface was used. Most American cars with
>> self-adjusting brakes use various methods to work the same way. VW decided
>> to go the way of placing the adjusting mechanism as the same end as the
>> cylinders. It should be noted that most air brake drum set ups on trucks
>> work the same way, (slack adjusters).
>>
>>
>>
>> Now this works well if everything is the proper dimensions, especially the
>> match between drum diameter and shoe thickness. A problem is that I have yet
>> to find replacement brake shoes that have the proper pad thickness or a
>> satisfactory material. For years I went to the dealer and got the OEM shoe
>> sets but they are no longer available. The original shoe linings were
>> riveted, metallic, high friction linings with a thickness of 6mm. The
>> aftermarket shoes are only 4mm and the linings are soft. It is also common
>> for some shoes to have the linings reversed (leading-trailing) or on the
>> shoe in the wrong place. Shimming the bottom compensates for the thinner
>> linings. This can also compensate for worn drums. The nuts and pins I
>> mentioned above will fit perfectly on the Vanagon if you want to add
>> adjustability. Since there are no detent springs to keep them from turning I
>> do not know if that could be a problem so I use shims. 2-3mm on each shoes
>> is a very good starting point.
>>
>>
>>
>> As these are self-adjusting brakes, I do not do any fine adjustment before
>> placing the drums. I want to know the self-adjusters work. I want to hear
>> them click!
>>
>>
>>
>> I have posted in the past instructions for installing and setting up the
>> rear brakes. There are a few details that are critical.
>>
>> The top springs have to be in the correct position, center hooks face up.
>> Otherwise they will hit the adjuster nut.
>>
>> The pushrod thread has to be able to turn freely. No grease or anti-seize. A
>> dry lube like lock-ease.
>>
>> The handbrake cable needs to be properly adjusted. This cannot be done with
>> the drum in place. You need to see the lever.
>>
>> After placing the shoes leave off the adjuster lever spring. The push rod
>> should be installed with the front chamfer facing the backing plate and on
>> the rear fork, the longer tang goes against the shoe. The shorter tang goes
>> in front of the lever. Adjust the push rod to take up the slack but do not
>> actually push out the shoes. Now notice how the hand brake can swing. Pull
>> forward and connect the brake cable. There should be about 1/16" between the
>> lever and the pushrod. Adjust the cable to give this on both sides. If the
>> cables appear to be binding or the outer jackets are collapsed or distorted
>> the cables need to be replaced.
>>
>> After this is sorted install the drums and make sure they are fully seated.
>> If needed bleed the brakes. Pumping the pedal will work the adjusters and if
>> there is any slack you should hear them click as they turn one notch with
>> each pedal push. Oh , and you want cylinders that have the inner springs to
>> prevent the pistons from retracting. This was recently a big discussion
>> here. ATE!
>>
>>
>>
>> I hope this helps.
>>
>>
>>
>> Dennis
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