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Re: Easy Brake Switch Inquiry

To: ",road" <datsun-roadsters@autox.team.net>
Subject: Re: Easy Brake Switch Inquiry
From: "Thomas Walter" <ra0618@email.sps.mot.com>
Date: Fri, 02 Jun 2000 07:39:39 -0500
Nathan,

With a mighty-vac applying the vacuum to the brake fluid to pull
it on through... well, if you apply a vacuum to the wheel cylinders,
air leaks right past the seal. Very difficult to get rid of all the
air that way!

It will work on disc brakes as the seal is much less likely to 
leak air past it.

Best bet is something like the speed bleeders (which I do not use
personally), or a friend to help bleed by the old "pump & hold"
method.

Personally I use a long length of tight fitting hose that goes
over the bleed nipple. I make a an "up and over" loop in the bleed
hose, crack open the bleeder and pump the brakes myself. The long
hose with the loop keeps fluid against the bleeding nipple when
I am not pumping. Also it will act as a syphon once you get the hose
full of fluid. Slow perhaps, but handy for those annual brake bleeding.

While a lot of people do NOT have success with my "one person method"
it always works for me... ahem, when I went to bleed the Land Cruiser
brakes and clutch, no go. Of course I tend to coat the bleeder valve
threads with anti-sieze, which prevents air from leaking past the
bleeders. For the Cruiser... old fashioned method... teaching my son
to "pump" and hollllllddddd it! ;-)

Cheers,

Tom Walter   '68 2000 --> Ironically this roadster is also from
Austin, TX                my home town of Sacramento. ;-)

nruff wrote:
> 
> Thanks for the quick replys.  I do have the pressure switch on the junction
> block, I should have made that more clear.  Yeah, I had better bleed the
> brakes.  The few short runs I've made were less than reassuring.  I used a
> "mighty vac" to bleed them myself, but have never been able to get a firm
> pedal on the roadster without a helper doing it the ol-fashion
> way-pump/hold.   On the same token, other systems I've worked, you could
> pump/hold all day and never get good pedal without the mighty-vac.  Go
> figure......
> Thanks again for the quick info!
> Nathan
> 
> > It was written:
> > > Brake switch is adjustable usually just above the pedal under the dash
> there
> > > should be a switch with wires coming out from it.
> >
> > '68 thru '70 used a switch on the pedal.
> > '67 and earlier used a pressure switch connected into the brake lines
> > (under the hood - follow the lines from the master cylinder). I don't
> > know if 67.5 used pressure switch or pedal switch - I suspect pedal
> > switch because the 67.5 also has the dual master.
> >
> > Air in the lines compresses, thus the lines don't build much pressure.
> > Bleed those brakes!
> >

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