Home » Public Forums » GMCnet » No Rear Brakes
| No Rear Brakes [message #110244] |
Thu, 30 December 2010 14:52  |
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WD0AFQ
Messages: 7111
Registered: November 2004
Location: Dexter, Mo.
Karma: 207
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Senior Member |
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Well, things are kinda slow here today. Snow and wind so not much else to do. Thought I might throw this brake problem out.
Last year we replaced the master cylendar as we arrived in Az. with no brakes. One of the rear lines was cracked so we cut it and re flared. Before I left Mo. I tried to check the brake fluid level. Could not get the lid off so I forgot all about it. Not good.
Half way across Tx, no brakes. The toad brake even broke. Roadmaster has replaced it already and gave me 860.00 credit toward their newest system. Will be eyeballing it at Quartzsite.
Anyway, I was able to pry the lid off the M/C. No fluid in front tank. Filled it up, still no brakes so through El Paso again this year, 10 wheels, 2 brakes.
Teri and I tried to bleed rear brakes. Fluid just barely trickles out when she applies brakes.
Now, and thanks to Rob M. for discussing this with me on the telephone, I am thinking I have air in the M/C. When the weather breaks I will try to bleed the front tank.
I hate drum brakes. Even plan to replace the Vdub brakes with discs when we get home.
So, this is where I am. Hoping I can just get enough brake to get me down the GLobe/Superior hill. If not, I will head to Quartzsite through Tucson and over 8 and up.
Dan
3 In Stainless Exhaust Headers
One Ton All Discs/Reaction Arm
355 FD/Quad Bag/Alum Radiator Manny Tran/New eng.
Holley EFI/10 Tire Air Monitoring System
Solarized Coach/Upgraded Windows
Satelite TV/On Demand Hot Water/3Way Refer
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| Re: [GMCnet] No Rear Brakes [message #110251 is a reply to message #110244] |
Thu, 30 December 2010 15:31  |
scott cowden
Messages: 170
Registered: February 2004
Karma: 0
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Senior Member |
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> Anyway, I was able to pry the lid off the M/C. No fluid in front tank. Filled it up, still no brakes so through El Paso again this year, 10 wheels, 2 brakes.
> Teri and I tried to bleed rear brakes. Fluid just barely trickles out when she applies brakes.
> Now, and thanks to Rob M. for discussing this with me on the telephone, I am thinking I have air in the M/C. When the weather breaks I will try to bleed the front tank.
> I hate drum brakes. Even plan to replace the Vdub brakes with discs when we get home.
> So, this is where I am. Hoping I can just get enough brake to get me down the GLobe/Superior hill. If not, I will head to Quartzsite through Tucson and over 8 and up.
> Dan
Dan;
I'm jealous to hear how many of you are getting to play with your m/h's this time of year. Mine is resting inside this year, but it's way too cold to even think about working on it.
As for your brake question, given your comments, if the system ran out of fluid while driving and you now can't get fluid to the back wheels even when someone is pressing on the brake pedal, I'd be checking the proportioning valve to see if it's not stuck in the 'front only' position. It'll do that if there's only pressure from one of the two sides of the master cylinder. likely to try to prevent further fluid loss and/or get the most from the remaining brake system. There's a detent button on the valve that will work to re-center the internal piston and once the piston is centred, fluid flow to the system previously damaged should be resumed.
If that doesn't get brake fluid flowing to the back wheels then you're likely stuck with a couple of scenario's: the lack of fluid or the extra brake stroke damaged the internals and the master cylinder is buggered, or there's a pinched line between the m/c and the rear wheels.
I don't know why the dislike for the brake drums, though. They're simple, really, and work pretty well when maintained properly. Most of the six disc systems I've seen have had several compromises and for all the work and the money spent have had the owners say it didn't do a lot to reduce stopping power. [if that comment doesn't get the wags going, nothing will!]
Happy new year, all, from the Great White North!
Scott Sudbury, ON, Canada
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| Re: [GMCnet] No Rear Brakes [message #110260 is a reply to message #110244] |
Thu, 30 December 2010 16:48 |
powerjon
Messages: 2446
Registered: January 2004
Karma: 5
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Senior Member |
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Dan,
I know that you're getting a lot of suggestion for your brake problem.
The first thing that you must do when installing a new master cylinder
is bench bleed the unit to get all the air out of the piston area.
You can do it in the coach, but be sure not to press the plunger very
deep into the unit when doing this. Another trick with the MC is to
drill a 3/16" hole in the wall between the 2 storage reservoirs about
3/8 of an inch down from the tip lip. This way you can fill both side
of the reservoir. Fill the back can be such a PIA.
When installing the MC unit in the coach and using to push brake fluid
to the wheel use Jim Bound caution method and put a 2 X 4 on its side
under the brake peddle to prevent you from pushing the piston too deep
into the unit and damaging the o-rings and having to start over.
I have always been able to gravity bleed the brakes on the coaches
that I have and do it once a year to keep fresh brake fluid in the
lines. You said that the front tank was empty, you need to find where
it is going to, could be a mystery hunt! You could have a combo valve
that is partly plugged and stuck. You didn't say if you were getting
a brake warning light.
You could have brake lines that are full of crud, how old are the rear
brake hoses on the bogey?
Lots of places to look!
J.R. Wright
GMC GreatLaker
TZE Zone Restorations
77 Eleganza Custom (For Sale)
1975 Avion (Under Reconstruction)
Michigan
On Dec 30, 2010, at 3:52 PM, Dan Gregg wrote:
>
>
> Well, things are kinda slow here today. Snow and wind so not much
> else to do. Thought I might throw this brake problem out.
> Last year we replaced the master cylendar as we arrived in Az. with
> no brakes. One of the rear lines was cracked so we cut it and re
> flared. Before I left Mo. I tried to check the brake fluid level.
> Could not get the lid off so I forgot all about it. Not good.
> Half way across Tx, no brakes. The toad brake even broke. Roadmaster
> has replaced it already and gave me 860.00 credit toward their
> newest system. Will be eyeballing it at Quartzsite.
> Anyway, I was able to pry the lid off the M/C. No fluid in front
> tank. Filled it up, still no brakes so through El Paso again this
> year, 10 wheels, 2 brakes.
> Teri and I tried to bleed rear brakes. Fluid just barely trickles
> out when she applies brakes.
> Now, and thanks to Rob M. for discussing this with me on the
> telephone, I am thinking I have air in the M/C. When the weather
> breaks I will try to bleed the front tank.
> I hate drum brakes. Even plan to replace the Vdub brakes with discs
> when we get home.
> So, this is where I am. Hoping I can just get enough brake to get me
> down the GLobe/Superior hill. If not, I will head to Quartzsite
> through Tucson and over 8 and up.
> Dan
> --
> Dan & Teri Gregg
>
> http://danandteri.blogspot.com/
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J.R. Wright
GMC GreatLaker
GMC Eastern States
GMCMI
78 30' Buskirk Stretch
75 Avion Under Reconstruction
Michigan
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| Re: [GMCnet] No Rear Brakes [message #110277 is a reply to message #110251] |
Thu, 30 December 2010 18:39 |
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USAussie
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
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Senior Member |
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G'day,
Reference Maintenance Manual X-7525 page 5-3:
COMBINATION VALVE
A combination valve is incorporated into the brake system. It performs three
functions: a balance function, a metering function, and a warning switch.
METERING VALVE FUNCTION
The metering section of the combination valve operates to "hold off"
hydraulic flow (pressure) until about 130 psi has been built up in the
system before applying the front brakes. The pressure then blends to full
line pressure at approx. 400-600 psi line pressure. There is no flow
restriction when the brakes are released.
BALANCE FUNCTION OR WARNING SWITCH
The fluid from the front and rear systems is separated by a hydraulically
balanced sealed piston. A spring loaded switch plunger rides in a groove in
the switch piston. Any pressure differential sufficient to overcome the
switch plunger spring and friction causes a shift of the piston in the
direction of reduced pressure, causing the switch pressure to ride up out of
its groove and the switch to make contact and light the warning light.
(100-300 psi differential is required).
In addition, this piston is designed to hydraulically recenter itself once
the pressure balance is restored (leak is fixed).
Reference Maintenance Manual X-7525 Page 5-14 Figure 3 - Tool J-23709
Installed and page 5-15:
BLEEDING WHEEL CYLINDERS WITHOUT PRESSURE TANK
3) Attach J-23709 to the combination valve (figure 3) to hold the push rod
in and allow pressure in the line to flow through the valve requiring less
pressure to bleed the front cylinder.
Below is a link to Ken Henderson's sequence of photographs showing the
disassembly, cleaning, and modification of the OEM combination valve to
remove the metering function should you put disk brakes on your GMC. It is
an EXCELLENT step by step procedure that clearly shows how the valve works
so I'm not going to bother to do so.
http://www.gmcmhphotos.com/photos/showphoto.php?photo=5314
Obviously this procedure can be used to rebuild the valve too; simply leave
the metering valve in it.
If you don't want to mess with this you can buy a new brass valve from Jim
K.
Regards,
Rob M.
USAussie - Downunder
AUS '75 Avion-The Blue StreakTZE365V100428
USA '75 Avion-Double Trouble TZE365V100426
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Regards,
Rob M. (USAussie)
The Pedantic Mechanic
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
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| Re: [GMCnet] No Rear Brakes [message #110283 is a reply to message #110277] |
Thu, 30 December 2010 19:14 |
James Hupy
Messages: 6806
Registered: May 2010
Karma: -62
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Senior Member |
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My strict advise is to not mess with the "Combination Valve" if you suspect
that it is defective, replace it with one of the brass ones from the Jim's.
I can tell you ahead of time, get ready for a hassle when breaking the
fittings loose. They are tighter than a miser's pinch on a dime, or other
comments appropriate to how mad you get when trying to loosen 35 year old
brake fittings. It is not inconcievable to round off all the fittings, and
when they finally do yield, to twist off the rusty brake lines as well. BTDT
too many times. It is stuff like that that makes working on these old
vehicles challenging/agravating. But the tough prevail and nothing worth
gaining is easily obtained according to my mother who lived through two
world wars and a great depression and still survived to watch live video of
the first men walking on the moon. Maybe the best of times and the worst of
times.
Jim Hupy
Salem, Or
78 GMC Royale 403
On Thu, Dec 30, 2010 at 4:39 PM, Rob Mueller <robmueller@iinet.net.au>wrote:
> G'day,
>
> Reference Maintenance Manual X-7525 page 5-3:
>
> COMBINATION VALVE
>
> A combination valve is incorporated into the brake system. It performs
> three
> functions: a balance function, a metering function, and a warning switch.
>
> METERING VALVE FUNCTION
>
> The metering section of the combination valve operates to "hold off"
> hydraulic flow (pressure) until about 130 psi has been built up in the
> system before applying the front brakes. The pressure then blends to full
> line pressure at approx. 400-600 psi line pressure. There is no flow
> restriction when the brakes are released.
>
> BALANCE FUNCTION OR WARNING SWITCH
>
> The fluid from the front and rear systems is separated by a hydraulically
> balanced sealed piston. A spring loaded switch plunger rides in a groove in
> the switch piston. Any pressure differential sufficient to overcome the
> switch plunger spring and friction causes a shift of the piston in the
> direction of reduced pressure, causing the switch pressure to ride up out
> of
> its groove and the switch to make contact and light the warning light.
> (100-300 psi differential is required).
>
> In addition, this piston is designed to hydraulically recenter itself once
> the pressure balance is restored (leak is fixed).
>
> Reference Maintenance Manual X-7525 Page 5-14 Figure 3 - Tool J-23709
> Installed and page 5-15:
>
> BLEEDING WHEEL CYLINDERS WITHOUT PRESSURE TANK
>
> 3) Attach J-23709 to the combination valve (figure 3) to hold the push rod
> in and allow pressure in the line to flow through the valve requiring less
> pressure to bleed the front cylinder.
>
> Below is a link to Ken Henderson's sequence of photographs showing the
> disassembly, cleaning, and modification of the OEM combination valve to
> remove the metering function should you put disk brakes on your GMC. It is
> an EXCELLENT step by step procedure that clearly shows how the valve works
> so I'm not going to bother to do so.
>
> http://www.gmcmhphotos.com/photos/showphoto.php?photo=5314
>
> Obviously this procedure can be used to rebuild the valve too; simply leave
> the metering valve in it.
>
> If you don't want to mess with this you can buy a new brass valve from Jim
> K.
>
> Regards,
> Rob M.
> USAussie - Downunder
> AUS '75 Avion-The Blue StreakTZE365V100428
> USA '75 Avion-Double Trouble TZE365V100426
>
>
>
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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| Re: No Rear Brakes [message #110288 is a reply to message #110244] |
Thu, 30 December 2010 19:36 |
g.winger
Messages: 792
Registered: February 2008
Location: Warrenton,Missouri
Karma: 0
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Senior Member |
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Dan,,,,I have a pressure bleeder I can send you if you want. Requires an air compresser. Its is an aluminum lid. Rubber gasket. Fittings, hoses, regulator,bleed valve and hold down chains. Easy to use. Fill,secure,tighten, appy air, bleed brakes, shut off air. bleed off air. remove. add fluid,,, repeat. let me know if you want it. You can ship it back later or bring back later.,,,,,,PL
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| Re: [GMCnet] No Rear Brakes [message #110295 is a reply to message #110283] |
Thu, 30 December 2010 19:48 |
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USAussie
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
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Senior Member |
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Jim,
Agreed!
Dan,
No matter if the Combination valve is original or one of these:
http://www.appliedgmc.com/prod.itml/icOid/770
You really need a set of these:
http://www.harborfreight.com/5-piece-sae-double-end-flare-nut-wrench-set-999
92.html
or for those of you who get upset when someone suggests buying HF tools ;-):
http://www.sears.com/shc/s/p_10153_12605_00942012000P?prdNo=2&blockNo=2&bloc
kType=G2
I would also spray the nuts with Kroil and let them soak.
Regards,
Rob M.
USAussie - Downunder
AUS '75 Avion-The Blue StreakTZE365V100428
USA '75 Avion-Double Trouble TZE365V100426
-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of James Hupy
Sent: Friday, December 31, 2010 12:15 PM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] No Rear Brakes
My strict advise is to not mess with the "Combination Valve" if you suspect
that it is defective, replace it with one of the brass ones from the Jim's.
I can tell you ahead of time, get ready for a hassle when breaking the
fittings loose. They are tighter than a miser's pinch on a dime, or other
comments appropriate to how mad you get when trying to loosen 35 year old
brake fittings. It is not inconcievable to round off all the fittings, and
when they finally do yield, to twist off the rusty brake lines as well. BTDT
too many times. It is stuff like that that makes working on these old
vehicles challenging/agravating. But the tough prevail and nothing worth
gaining is easily obtained according to my mother who lived through two
world wars and a great depression and still survived to watch live video of
the first men walking on the moon. Maybe the best of times and the worst of
times.
Jim Hupy
Salem, Or
78 GMC Royale 403
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GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Regards,
Rob M. (USAussie)
The Pedantic Mechanic
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
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| Re: [GMCnet] No Rear Brakes [message #110296 is a reply to message #110295] |
Thu, 30 December 2010 19:54 |
James Hupy
Messages: 6806
Registered: May 2010
Karma: -62
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Senior Member |
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Rob, the Craftsman or SnapOn ones are worth every dime. They are not as
bulky around the business end and will fit where the cheapo ones don't. Had
a set for many years and would not attempt to loosen those fittings without
one.
Jim Hupy
Salem, Or
78 GMC Royale 403
On Thu, Dec 30, 2010 at 5:48 PM, Rob Mueller <robmueller@iinet.net.au>wrote:
> Jim,
>
> Agreed!
>
> Dan,
>
> No matter if the Combination valve is original or one of these:
>
> http://www.appliedgmc.com/prod.itml/icOid/770
>
> You really need a set of these:
>
>
> http://www.harborfreight.com/5-piece-sae-double-end-flare-nut-wrench-set-999
> 92.html
>
> or for those of you who get upset when someone suggests buying HF tools
> ;-):
>
>
> http://www.sears.com/shc/s/p_10153_12605_00942012000P?prdNo=2&blockNo=2&bloc
> kType=G2
>
> I would also spray the nuts with Kroil and let them soak.
>
> Regards,
> Rob M.
> USAussie - Downunder
> AUS '75 Avion-The Blue StreakTZE365V100428
> USA '75 Avion-Double Trouble TZE365V100426
>
> -----Original Message-----
> From: gmclist-bounces@temp.gmcnet.org
> [mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of James Hupy
> Sent: Friday, December 31, 2010 12:15 PM
> To: gmclist@temp.gmcnet.org
> Subject: Re: [GMCnet] No Rear Brakes
>
> My strict advise is to not mess with the "Combination Valve" if you suspect
> that it is defective, replace it with one of the brass ones from the Jim's.
> I can tell you ahead of time, get ready for a hassle when breaking the
> fittings loose. They are tighter than a miser's pinch on a dime, or other
> comments appropriate to how mad you get when trying to loosen 35 year old
> brake fittings. It is not inconcievable to round off all the fittings, and
> when they finally do yield, to twist off the rusty brake lines as well.
> BTDT
> too many times. It is stuff like that that makes working on these old
> vehicles challenging/agravating. But the tough prevail and nothing worth
> gaining is easily obtained according to my mother who lived through two
> world wars and a great depression and still survived to watch live video of
> the first men walking on the moon. Maybe the best of times and the worst of
> times.
> Jim Hupy
> Salem, Or
> 78 GMC Royale 403
>
>
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
_______________________________________________
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List Information and Subscription Options:
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| Re: [GMCnet] No Rear Brakes [message #110301 is a reply to message #110263] |
Thu, 30 December 2010 21:06 |
Carl S.
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
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Senior Member |
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| WD0AFQ wrote on Thu, 30 December 2010 15:57 |
My thought was to gravity bleed them but when only a little fluid came out I diecided to have Teri help me. The fluid leaked out the line that we repaired last year. Was a very slow leak that took a year. The rear brake rubber lines I got from Jim B back in 05 and put them on in 06. The steel lines were replaced in 06. I will see if I can bleed the master when the weather warms back up. If not, I will ease around through Tucson to Quartzsite where I will ask for help from our friends that will be there.
Thanks,
Dan
|
Dan,
If you decide to go through Tucson, I will take the tme to help with the brakes. We will get them working. I wouldn't want to drive to Quartzsite without brakes and I wouldn't want one of my friends to do it either.
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
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| Re: No Rear Brakes [message #110325 is a reply to message #110244] |
Fri, 31 December 2010 00:46 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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Senior Member |
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Bench bleed (on the coach) the front of the master cylinder which is the rear brakes. Then get one of these from Harbor Freight for $26.00 and bleed the entire rear system.
http://www.harborfreight.com/brake-bleeder-and-vacuum-pump-kit-92474.html
I borrowed Emery's vacuum bleeder at Rayne when I had a problem and it worked great. I bought one when you and I went to Harbor Freight in Pueblo. Too bad you did not get one at the same time.
You are going to have to bleed rears even if you decide to switch to rear disks now or later. They all require a hydraulic system free from air.
It looks like Quartzsite in a NO GO for me. If things change I'll let you know.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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| Re: [GMCnet] No Rear Brakes [message #110335 is a reply to message #110250] |
Fri, 31 December 2010 06:35 |
Steven Ferguson
Messages: 3447
Registered: May 2006
Karma: 0
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Senior Member |
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Dan,
What Hardie posted is the way to go. I keep several sets of pre-bent lines
with different size fittings on them just for this purpose. Getting air out
of a MC is a painful process and it doesn't make any difference what type of
brakes you have on the other end. (Disk or drum). The procedure is the
same. I have fought master cylinders for longer than I care to admit only
to that you can't effectively remove the air from any system unless you
bench bleed the MC first.
On Thu, Dec 30, 2010 at 2:30 PM, Hardie Johnson <hardie.j@gmail.com> wrote:
>
>
> WD0AFQ wrote on Thu, 30 December 2010 15:52
> > <>I was able to pry the lid off the M/C. No fluid in front tank. Filled
> it up, still no brakes so through El Paso again this year, 10 wheels, 2
> brakes. Teri and I tried to bleed rear brakes. Fluid just barely trickles
> out when she applies brakes.<>Dan
>
> I have heard we should bench bleed the master cylinder or it will never get
> the air our. What might work would be to rig some short lines to feed the
> brake fluid back into the reservoir and pump until there are no more
> bubbles.
> I have had much better luck fixing brakes with a pressure bleeder,
> especially when long lines or complex routing is involved. You just can't
> pump that much. Also a good detail is to use a different color brake fluid
> each time you do this. Summit Racing has red and blue available. This way
> you know when the cycle is getting complete.
> "in with the good fluid, out with the bad"
>
> --
> Hardie Johnson "Crashj"
> 1973 26 foot Glacier, White Thing
> Raleigh NC
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
--
Steve Ferguson
Sierra Vista, AZ
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| Re: [GMCnet] No Rear Brakes [message #110345 is a reply to message #110335] |
Fri, 31 December 2010 08:22 |
Surbo
Messages: 213
Registered: February 2004
Karma: 0
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Senior Member |
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| Steven Ferguson wrote on Fri, 31 December 2010 06:35 |
Dan,
What Hardie posted is the way to go. I keep several sets of pre-bent lines
with different size fittings on them just for this purpose. Getting air out
of a MC is a painful process and it doesn't make any difference what type of
brakes you have on the other end. (Disk or drum). The procedure is the
same. I have fought master cylinders for longer than I care to admit only
to that you can't effectively remove the air from any system unless you
bench bleed the MC first.
On Thu, Dec 30, 2010 at 2:30 PM, Hardie Johnson <hardie.j@gmail.com> wrote:
>
>
> WD0AFQ wrote on Thu, 30 December 2010 15:52
> > <>I was able to pry the lid off the M/C. No fluid in front tank. Filled
> it up, still no brakes so through El Paso again this year, 10 wheels, 2
> brakes. Teri and I tried to bleed rear brakes. Fluid just barely trickles
> out when she applies brakes.<>Dan
>
> I have heard we should bench bleed the master cylinder or it will never get
> the air our. What might work would be to rig some short lines to feed the
> brake fluid back into the reservoir and pump until there are no more
> bubbles.
> I have had much better luck fixing brakes with a pressure bleeder,
> especially when long lines or complex routing is involved. You just can't
> pump that much. Also a good detail is to use a different color brake fluid
> each time you do this. Summit Racing has red and blue available. This way
> you know when the cycle is getting complete.
> "in with the good fluid, out with the bad"
>
> --
> Hardie Johnson "Crashj"
> 1973 26 foot Glacier, White Thing
> Raleigh NC
> _______________________________________________
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Steve Ferguson
Sierra Vista, AZ
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Tip for bench bleeding a MC. This will speed up a MC bench bleed. Put MC in a vise, front end slightly lower (or higher), install short lines in the brake line outlets. Fill compartments with fluid, and using a vac source, very slowly apply vac to each line until most of the air is sucked out. Tilt the MC the opposite way, and do the vac again. Don't let the fluid get too low in the MC. You may want to re-tilt the MC several times and do a little more vac to get most of the air out. Remove the vac supply from the lines and bend them into the MC compartments and get them below the fluid level. To finish up, slowly move the plunger in the MC, only about an inch, release for 15 secs and repeat until you see no air bubbles.
You can also use a syringe and push fluid into the line outlets to help in bleeding the MC.
Bob Drewes in SESD
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| Re: [GMCnet] No Rear Brakes [message #110375 is a reply to message #110372] |
Fri, 31 December 2010 13:27 |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
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Senior Member |
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19*F!? Here I've been envying you & Teri your winter evacuation of
cold country -- It's 74.6*F here right now, with a couple more hours
'til the maximum for the day. :-) My green complexion has faded. :-)
The human mind's ability to blank out unpleasant memories is working
on that 22*F a couple of nights ago.
Ken H.
On Fri, Dec 31, 2010 at 1:32 PM, Dan Gregg <gregg_dan@hotmail.com> wrote:
>
>... At 19 this morning it is a bit chilli. Up to 38 now...
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
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