Date: Sun, 4 May 2014 21:04:48 -0600
Reply-To: Gnarlodious <gnarlodious@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Gnarlodious <gnarlodious@GMAIL.COM>
Subject: Re: CV Joints
In-Reply-To: <CAFNeVpHQrdFYvY8GS-NPrcFmdRWp1gSvmJHfhxYJT_aUY71bdg@mail.gmail.com>
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Anyone who is aware of the principle of the CV joint knows they must
move in and out freely to the extent of their stroke. If the star
driver is installed backwards it doesn't do that. In fact you probably
can't even install the axle if it is assembled wrong because the joint
won't pivot.
One detail beginners make the mistake of is that the joint must not be
pivoted to the extremes of its rotation or the balls can pop out
inside the boot. One reason the boot is tight is to keep the balls in.
This can happen in case of broken motor mounts or a collision shifted
engine. Mostly a problem in front wheel drive cars though, not the
Vanagon.
Also, high slung vans get quite a lot more CV abuse that the Carat or
other lowrider models. It's all about the angle of the pivot.
The boot can't possibly hold anything in alignment, it doesn't have
that much strength. I can understand how clamping them too far out can
put extra flexing stress on the rubber. The axle has a ridged area
that holds the boot in position. Seems pretty clear that they are
expected to be tight and look like a closed accordion.
No doubt the poor quality of rubber is the main cause of boot
breakage, but I am convinced environmental factors are also a factor.
I suspect that both ozone and UV cause premature deterioration of the
rubber. We do know that ozone attacks rubber, in fact some rubber is
made ozone resistant by saturating it with sacrificial molecules that
offer themselves up in place of the rubber. I don't know if there are
any CV boots with this feature.
I live at 7,200 feet where there is strong UV. Apparently when you are
out on a mountaintop and the sun is on the horizon and rays are
hitting your CV joints directly, that is the worst case scenario. But
I have a feeling there is plenty of UV just bouncing around that gets
in under your van. Supposedly you can spray a rubber preserver like
Black Magic onto your boots and that should lengthen their life
expectancy. I did a search for such a test but found none. So when I
put on new boots last fall I started an experiment, Black Magic on the
one exposed boot twice a year. I'll see in a few years if it has made
any difference.
Its a damnable problem.
-- Gnarlie
On Sun, May 4, 2014 at 3:28 PM, Tom Carchrae <tom@intellecti.ca> wrote:
> I came across this thread that pointed me at how to clock your CV joints.
> It basically involves ensuring that the wide/narrow parts of the CV do not
> match. The theory all seems very sane to me.
> http://www.thesamba.com/vw/forum/viewtopic.php?p=7038607#7038607http://www.thesamba.com/vw/forum/viewtopic.php?p=7038607#7038607
>
> Have any of you heard of this before?
>
> I read somewhere about people adjusting the small end of CV boots further
> toward the centre of the axle to stop "clacking" - that sounds like perhaps
> it could be a bad way of fixing an 'unclocked' axle.
>
> Perhaps this accounts for a higher CV boot failure as well? All seems
> plausible. Certainly better quality boots will last longer, but asking a
> CV boot to hold the joint in alignment seems like the wrong part doing the
> work.
>
> Tom
>
>
> http://intellecti.ca - scheduling and optimization technology
>
>
>
>
> On Wed, Apr 30, 2014 at 12:51 PM, Project Pat <psdooley@verizon.net> wrote:
>
>> My experience with Rockford was many years ago, put 4 new boots on a
>> Scirocco; 2 of them failed within a couple months.
>> Of course that was years ago and YMMV.
>>
>>
>> -----Original Message-----
>> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
>> Gnarlodious
>> Sent: Wednesday, April 30, 2014 2:15 PM
>> To: vanagon@GERRY.VANAGON.COM
>> Subject: Re: CV Joints
>>
>> A company called Rockford allegedly makes a high quality
>> Elastopolymer...
>>
