Date: Sun, 12 Apr 2009 17:10:05 -0700
Reply-To: neil N <musomuso@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: neil N <musomuso@GMAIL.COM>
Subject: Re: Trying To Understand Tie rod Adjustments
In-Reply-To: <BLU0-SMTP34D5A59F48B0ADF6ECF019DA7E0@phx.gbl>
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On Sun, Apr 12, 2009 at 4:05 PM, Keith Hughes <keithahughes@q.com> wrote:
>> Date: Sun, 12 Apr 2009 13:50:36 -0700
>> From: neil N <musomuso@GMAIL.COM>
>> Subject: Re: Trying To Understand Tie rod Adjustments
>>
>> The original goal; align things by my "shade tree" hand so I could drive
>> it=
>> .
>>
>> Current goal: see if changing castor on passenger side help RH drift.
>> Mostly for learning.
>>
>
> Well, it's "caster" to be correct, "castor" is a bean :-)
>
> IME, caster rarely causes a consistent pulling to one side or the
> other. That's typically camber and/or toe in.
>>
>> I will take it to a shop. If my adjustment corrects drift, I'll be
>> curious to see how close i got toe and castor. (I'm not dicking with
>> the camber)
>>
> Well, yes you are actually. If you adjust the caster, you'll be
> adjusting the camber as well. To understand why, just think of a
> transverse line running through the two front wheel hubs. To adjust
> caster without affecting the camber, the radius arms would have to be
> perpendicular to that transverse line so that when you increase caster
> by nudging the control arm rearward, the vertical plane running through
> the upper and lower ball joints is not changed (i.e. the lower ball
> joint would move *straight* back). Since the radius arms are at an
> angle to that transverse line through the wheel hubs, adjusting caster
> also moves the lower ball joint either IN or OUT as well forward/backward.
>
> Unless your tires are already beat, take it to a shop. It's money well
> spent. Once you start getting a scalloped wear pattern from bad toe
> adjustment, or inner/outer wear from bad camber, you'll never get them
> to wear right again.
>
> Keith Hughes
> '86 Westy Tiico (Marvin)
>
Heh. Thanks for the spell check. ;)
Yah. I adjusted the caster to "original" position (easy to see due to
corrosion) by 2 turns. +/- 1/2 turn. No difference.
On the way back, I thought of how the radius arm is on an angle and
considered how adjusting caster actually works. Thanks for the "how"
etc. Considering radius arm is attached to the lower control arm, I
was curious about how caster adjustment movement is "allowed". I
imagine the rubber in the control arm bushing permits this. Albeit a
small movement at end of lower control arm.
Yah I suspect it's toe adjustment. It was driving like I was in a
cross wind. Correcting by turning wheel to left to keep from drifting
right.
( in that case RH wheel toed out, increase toe in? Or LH wheel toed
in: adjust toe out?)
Neil.
--
Neil Nicholson '81 VanaJetta 2.0 "Jaco"
http://tubaneil.googlepages.com/
http://groups.google.com/group/vanagons-with-vw-inline-4-cylinder-gas-engines
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