Date: Mon, 1 Jun 2009 19:36:21 -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: Rolling Friction of a Vanagon (not a tire thread)!
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re the questions about the wheels turning ......
it's obviously in a gear.......which means with engine running, rear wheels
off the ground........
one or both of them will turn.
'if' the brake drag on each rear wheel was identical..........you might get
both rear wheels not turning, or barely turning, or turning equally.
If there is more drag on one side or the other .......that draggy wheel will
be stationary, and the other one will turn, due to having 'a open
differential' ........which divides drive to both rear wheels equally when
the load on each is equal.....
like when going straight down a paved road ...........but it's always free
to turn just one side .......you could jack up just one rear wheel, start up
the engine, let out the clutch .....and only that one whell will turn. All
because it has a conventional 'open differential' . - a divice that some
people do not understand too well it seems.
as for when the engine is off, both wheels in the air ............and you
turn one rear wheel by hand, and the other turns the opposite way
.........perfectly normal, if it's in gear. If it was in neutral.......you
could turn one rear wheel and the other won't turn, or at least won't be
driven with any force on it.
if you've even seen a trans with a seized pnion shaft, or seized ring and
pinion ...........what you see is that the only turning the rear wheels will
do is ......each one turning in the oppostie direction of the other - due to
the spider gears in the differential and how they work.
'most' two piston, 1980 to 1985 vanagon front calipers either have been
replaced by now, or they have binding, or stuck, inner ( usually it's the
inner piston ) pistons. Quite common on those years vanagons. Rebuilt front
calipler is the usual repair. Brake fluid must be changed every two years
on all cars.
Brake fluid absorbs moisture out of the air .......even just sitting
there...........corrosion is happening, if the brake fluid isn't reasonably
fresh.,
Scott
turbovans
----- Original Message -----
From: "Poppie Jagersand" <poppie.jagersand@YAHOO.CA>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Sunday, May 31, 2009 9:11 PM
Subject: Re: Rolling Friction of a Vanagon (not a tire thread)!
> Scenario 1 ought to give slightly less friction since fewer gears in the
> transmission are being turned from the wheels. Difference is unlikely to
> be noticeable though.
>
> Martin
>
> --- On Sun, 5/31/09, John Rodgers <inua@CHARTER.NET> wrote:
>
>> My question is: Which scenario below will offer the least
>> resistance or
>> friction to oppose momentum.
>>
>> Given:
>>
>> Scenario #1: At speed, the clutch is depressed, the
>> transmission is
>> placed in neutral, then the clutch pedal is released
>> and remains there
>> until roll out is complete
>>
>> Or;
>>
>> Scenario #2: At speed, the engine is disengaged from
>> the tranny by
>> simply pushing in the clutch and holding it there until my
>> roll-out is
>> completed.
>>
>> Anyone ever looked at this difference?
>>
>> Thanks,
>>
>> Regards,
>>
>> John Rodgers
>> 88 GL Driver
>>
>
>
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