ShopTalk Forums | Aircooled VW Tech & Restoration Help

The latest DB&HVWs magazine (Jan 2003) "Tech Talk" advises someone to correct their bug's poor braking by lengthening the master cylinder pushrod...."you can increase the leverage applied to the master cylinder, thus making it more efficient"...and then goes on to recommend adjusting the brakes, etc.
The M/C pushrod length is not supposed to be tampered with - it is factory-set and you are supposed to adjust the brake pedal freeplay by adjusting the pedal stop on the floor. Overadjusting it in an attempt to improve the braking can only result in defeating the function of the compensating ports inside the M/C with the result that the brakes will lock up and not release after a short period of driving.
Anyone with an ounce of mechanical aptitude can see that adjusting it doesn't change any "leverage" in the system, but unfortunately that doesn't seem to be a prerequisite for the position of Technical Editor at this rag.
I vented here because it could take two months before they print their retraction and a lot of people who believe what they read in the magazines could f*ck up their brakes between now & then.
If your brakes need attention, this is NOT the place to start. Make sure there is pedal freeplay, sure (but that's usually more a matter of cleaning out rocks & dirt from the pedal stop area), but stay away from the pushrod length adjustment unless you know exactly what you're doing.

Thanks Marc, nice catch...

but, before we jump to conclusions maybe we should contact them... Who knows, they could have disproved the laws of physics!!!

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Project Farfrumwerken -- New Updates!

Pimped OUT

Holy smokes! That could be dangerous!
What do you think they were trying to do? Are they just making this stuff up? Are they really trying to tell Joe Average that re-engineering his braking system is the answer to a lack of routine maintenance?

Sorry, Hot VW's, you ain't so hot...

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Jason Hamilton
The Online Karmann Ghia Resource
1969 & 1970 Type 143

You are correct sir!!!!!

Dang and to think I just ordered a long pushrod...I'm going to e-mail the tech articles I'm doing to Marc first to be verified....

Scott

are you saying size doesn't matter???

Seriously... it just bad advice...

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by aircooled1:
<B>are you saying size doesn't matter???

Seriously... it just bad advice...</B><HR></BLOCKQUOTE>

i sure hope my wife dosent read it . my grage sure gets cold this time of year

I wonder why bob hoover called them t1t$ & @ss magazines

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Marc:
<B>The latest DB&HVWs magazine (Jan 2003) "Tech Talk" advises someone to correct their bug's poor braking by lengthening the master cylinder pushrod...."you can increase the leverage applied to the master cylinder, thus making it more efficient"...and then goes on to recommend adjusting the brakes, etc.
The M/C pushrod length is not supposed to be tampered with - it is factory-set and you are supposed to adjust the brake pedal freeplay by adjusting the pedal stop on the floor. Overadjusting it in an attempt to improve the braking can only result in defeating the function of the compensating ports inside the M/C with the result that the brakes will lock up and not release after a short period of driving.
Anyone with an ounce of mechanical aptitude can see that adjusting it doesn't change any "leverage" in the system, but unfortunately that doesn't seem to be a prerequisite for the position of Technical Editor at this rag.
I vented here because it could take two months before they print their retraction and a lot of people who believe what they read in the magazines could f*ck up their brakes between now & then.
If your brakes need attention, this is NOT the place to start. Make sure there is pedal freeplay, sure (but that's usually more a matter of cleaning out rocks & dirt from the pedal stop area), but stay away from the pushrod length adjustment unless you know exactly what you're doing.</B><HR></BLOCKQUOTE>

I replaced a master cylinder a long time and messed around with changed the length of the rod. It made the brake pedal have the incorrect free play and caused the wheels to have smoke come out of the brake drum from dragging and the car would hardly stop. That rod is not supposed to be changed. That is some bad advice to tell someone to change that.

There must be some provision for adjustment if the pedal assembly has been removed and rebuilt. I know I should have marked it when I removed it, but with the threads and locknut, I thought there must be some adjustment.

Does anyone know how to set it back to the factory setting? How many threads or how many mm from the end? Or is it set by feel when it contacts the MC piston?

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AMAC

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by CT_GHIA_70:
<B>Does anyone know how to set it back to the factory setting?

</B><HR></BLOCKQUOTE>
http://shoptalkforums.com/bbs/NonCGI/Fo ... 03571.html
(sixth post in this thread details adjustment procedure)

Thanks, Marc!

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AMAC

according to the book here in front of me.the adjustments are,,1/4"play at the top of the peddle.read closely,,.04"between the push rod and the cylinder in master cly.just my 02 worth.

I only looked at the girls in the magazines, but they are scarce anymore so I stop subscribing years ago.

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by rich2481:
I only looked at the girls in the magazines, but they are scarce anymore so I stop subscribing years ago.<HR></BLOCKQUOTE>

you might try a vw mag the next time,maybe look at the pic,s in hot vws.