Ford A426C vacuum pump issues

LarryW

LarryW

Well-known member
Mar 28, 2002
6,039
764
113
Menomonie, WI.
Several years ago I purchased a Ford Azure vacuum pump and installed it under the drivers side hatch on my coach. As you all know it is used in
conjunction with the vacuum booster to provide braking vacuum in the event that the engine should quit. The pump has worked flawlessly until several
weeks ago when it stopped pumping. It just blew 20 amp fuses. I took the thing off and disassembled it. I found the crankshaft inside corroded badly
enough to seize the shaft so that the motor could not turn the crank. I soaked the crank with Kroil for about an hour and twisted it with a channel
lock and eventually broke it loose. I was surprised at how much corrosion I found inside of the pump.

Does anyone know where the pump was located on the Ford Azure? Considering the amount of corrosion inside the pump, I think that locating it under
the hatch (as many of us have done) is no longer advisable. It needs to be located in a place that is less exposed to the elements. Any suggestions?

If your pump is located under the hatch as in this picture

http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p55693-img-10802.html

I would advise pulling the filter off of the front of the pump and check to see if any corrosion has taken place. The filter housing is located
opposite the electric motor in this picture.

http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p55680-img-10841.html

here:

http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p64527-img-12381.html

and here

http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p64526-img-12371.html

I'd hate to see this thing lock up on you all when you need it most.

Just what I'd do.

--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
 
Dang - Thanks Larry - that's kinda where mine is installed - but tucked up a little higher and to the drivers side.

I used some bracketry from Dave Lenzi.

I recall reading that the newer versions of this pump were of a composite material rather than aluminum... maybe that's related.

Steve W
1973 23'
Southern California
 
Larry,

I don't know where the pump was located on the Azure; however, here's where it is on the F-150

https://www.youtube.com/watch?v=sxo2QVwbDkI

Scroll in to 3:00 minutes.

IIRC Dave Lenzi removed the horns and stuck his as high up in that area as possible; well above and to the right of the hood.

From looking at your photos I see the vacuum hook up is at the bottom with the hose facing towards the booster. It appears that the
exhaust was facing up; however, I can't tell that for sure. If it was I'd guess that's how the water got in to the pump.

I mounted the one on The Blue Streak behind the bracket that Ken's electric windshield wipers mount to and I made a hood that
extends over the exhaust filter.

Unfortunately I can't provide any photos as I can't drive with my arm in a sling so I can't get to my workshop.

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces] On Behalf Of Larry
Sent: Thursday, February 8, 2018 2:40 PM
To: gmclist
Subject: [GMCnet] Ford A426C vacuum pump issues

Several years ago I purchased a Ford Azure vacuum pump and installed it under the drivers side hatch on my coach. As you all know it
is used in conjunction with the vacuum booster to provide braking vacuum in the event that the engine should quit. The pump has
worked flawlessly until several weeks ago when it stopped pumping. It just blew 20 amp fuses. I took the thing off and disassembled
it. I found the crankshaft inside corroded badly
enough to seize the shaft so that the motor could not turn the crank. I soaked the crank with Kroil for about an hour and twisted it
with a channel lock and eventually broke it loose. I was surprised at how much corrosion I found inside of the pump.

Does anyone know where the pump was located on the Ford Azure? Considering the amount of corrosion inside the pump, I think that
locating it under the hatch (as many of us have done) is no longer advisable. It needs to be located in a place that is less exposed
to the elements. Any suggestions?

If your pump is located under the hatch as in this picture

http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p55693-img-10802.html

I would advise pulling the filter off of the front of the pump and check to see if any corrosion has taken place. The filter
housing is located
opposite the electric motor in this picture.

http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p55680-img-10841.html

here:

http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p64527-img-12381.html

and here

http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p64526-img-12371.html

I'd hate to see this thing lock up on you all when you need it most.

Just what I'd do.

--
Larry
78 Royale w/500 Caddy
Menomonie, WI.

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Unsubscribe or Change List Options:
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> Larry,
>
> I don't know where the pump was located on the Azure; however, here's
> where it is on the F-150
>
> https://www.youtube.com/watch?v=sxo2QVwbDkI
>
> Scroll in to 3:00 minutes.
>
> IIRC Dave Lenzi removed the horns and stuck his as high up in that area as
> possible; well above and to the right of the hood.
>
> From looking at your photos I see the vacuum hook up is at the bottom with
> the hose facing towards the booster. It appears that the
> exhaust was facing up; however, I can't tell that for sure. If it was I'd
> guess that's how the water got in to the pump.
>
> I mounted the one on The Blue Streak behind the bracket that Ken's
> electric windshield wipers mount to and I made a hood that
> extends over the exhaust filter.
>
> Unfortunately I can't provide any photos as I can't drive with my arm in a
> sling so I can't get to my workshop.
>

Sooo, what happened to your arm?.


> Regards,
> Rob M.
> The Pedantic Mechanic
> Sydney, Australia
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
> USA '77 Kingsley - TZE 267V100808
>
>
> -----Original Message-----
> From: Gmclist [mailto:gmclist-bounces] On Behalf Of Larry
> Sent: Thursday, February 8, 2018 2:40 PM
> To: gmclist
> Subject: [GMCnet] Ford A426C vacuum pump issues
>
> Several years ago I purchased a Ford Azure vacuum pump and installed it
> under the drivers side hatch on my coach. As you all know it
> is used in conjunction with the vacuum booster to provide braking vacuum
> in the event that the engine should quit. The pump has
> worked flawlessly until several weeks ago when it stopped pumping. It just
> blew 20 amp fuses. I took the thing off and disassembled
> it. I found the crankshaft inside corroded badly
> enough to seize the shaft so that the motor could not turn the crank. I
> soaked the crank with Kroil for about an hour and twisted it
> with a channel lock and eventually broke it loose. I was surprised at how
> much corrosion I found inside of the pump.
>
> Does anyone know where the pump was located on the Ford Azure?
> Considering the amount of corrosion inside the pump, I think that
> locating it under the hatch (as many of us have done) is no longer
> advisable. It needs to be located in a place that is less exposed
> to the elements. Any suggestions?
>
> If your pump is located under the hatch as in this picture
>
>
> http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p55693-img-10802.html
>
> I would advise pulling the filter off of the front of the pump and check
> to see if any corrosion has taken place. The filter
> housing is located
> opposite the electric motor in this picture.
>
>
> http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p55680-img-10841.html
>
> here:
>
>
> http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p64527-img-12381.html
>
> and here
>
>
> http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p64526-img-12371.html
>
>
> I'd hate to see this thing lock up on you all when you need it most.
>
> Just what I'd do.
>
>
> --
> Larry
> 78 Royale w/500 Caddy
> Menomonie, WI.
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://bdub.net/gmcmotorhome.info/
Alternator Protection Cable
http://bdub.net/gmcmotorhome.info/APC.html
 
> Larry,
>
> From looking at your photos I see the vacuum hook up is at the bottom with the hose facing towards the booster. It appears that the
> exhaust was facing up; however, I can't tell that for sure. If it was I'd guess that's how the water got in to the pump.
>
> Regards,
> Rob M.

Rob, When I installed the pump, I recognized the issue with the exhaust facing up, so took the time to remove the exhaust filter and turn it so it
was facing down. Also placed a piece of rubber conveyer belt material over the pump to deflect water that may get in around the hatch. Obviously was
not enough. I've let the pump crank soak overnight with Kroil and today I'm going to flush it out in my parts cleaner. Then will coat the crank and
filter good with "Corrosion X"
https://www.amazon.com/Corrosion-X-90102-Anti-Corrosion-Lubricant-16-Ounce/dp/B003HFTI0S/ref=sr_1_1?ie=UTF8&qid=1518101178&sr=8-1&keywords=corrosion-x
My son-in-law put me on to this stuff 4 or 5 yrs ago and it has eliminated misc. issues I've had with corrosion in coach and home. I don't really
want to move the pump so will also be pulling the exhaust/filter every year to check it. Just what I'm gonna do.
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
 
Maybe the moisture is resulting from the vapors being vacuumed and is somehow making its way into the crankcase. Condensation would be possible with
many temperature/pressure combinations and might have built up over the period of use and never had a way out. And there is a lot of moisture in the
engine fumes that may have gone through the system, depending on your plumbing setup.
--
Terry Kelpien

ASE Master Technician

73 Glacier 260

Smithfield, Va.
 
Larry,
It looks that you have mounted the pump in a location that allow the water and road spray to drip onto the vacuum pump from the top of the door seam.
when I installed the vacuum pump in our first using a GM pump that everyone was using at the time (no longer available) I put it in the location that everyone was using at the time. I noticed after the first trip that water had dripping on the pump. I put a drip shield over the pump to protect it from it getting wet in the future and that pump was still working without issue in 2011 (11 years) when we sold the coach.

First vacuum pump I used in 2000:
http://www.gmcmhphotos.com/photos/vacuum-pump-vacuum-switch/p1606.html
http://www.gmcmhphotos.com/photos/vacuum-pump-vacuum-switch/p1605.html
http://www.gmcmhphotos.com/photos/vacuum-pump-vacuum-switch/p1604.html

When we bought the stretch coach in 2011 it did not have a additional vacuum pump other than a additional small vacuum tank. The Ford pump was mounted (in 2013) as far back in the cavity as I could. It is an area that stays dry and the picture is little misleading as it sits up high and doesn’t get wet, While we are in Tucson the coach is in storage here in the RV park and I will walk over and see if I can get any additional shots that show the small vacuum tank and pump layout.

Ford A426C pump installed in the Buskirk stretch:
http://www.gmcmhphotos.com/photos/general-pictures/p59295-dl-brake-layout.html

Water has always been a problem as it comes off the windshield and leaks into the compartment thru the door seam. A lot of GMC’ers have installed water drip shields to direct the water away from the vacuum pump, master cylinder and other under the cover items.

J.R. Wright
GMC GreatLakerTech Editor
78 Buskirk 30' Stretch
75 Avion Under Reconstruction
Michigan (On Location in Tucson)

>
> Several years ago I purchased a Ford Azure vacuum pump and installed it under the drivers side hatch on my coach. As you all know it is used in
> conjunction with the vacuum booster to provide braking vacuum in the event that the engine should quit. The pump has worked flawlessly until several
> weeks ago when it stopped pumping. It just blew 20 amp fuses. I took the thing off and disassembled it. I found the crankshaft inside corroded badly
> enough to seize the shaft so that the motor could not turn the crank. I soaked the crank with Kroil for about an hour and twisted it with a channel
> lock and eventually broke it loose. I was surprised at how much corrosion I found inside of the pump.
>
> Does anyone know where the pump was located on the Ford Azure? Considering the amount of corrosion inside the pump, I think that locating it under
> the hatch (as many of us have done) is no longer advisable. It needs to be located in a place that is less exposed to the elements. Any suggestions?
>
> If your pump is located under the hatch as in this picture
>
> http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p55693-img-10802.html
>
> I would advise pulling the filter off of the front of the pump and check to see if any corrosion has taken place. The filter housing is located
> opposite the electric motor in this picture.
>
> http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p55680-img-10841.html
>
> here:
>
> http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p64527-img-12381.html
>
> and here
>
> http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p64526-img-12371.html
>
> I'd hate to see this thing lock up on you all when you need it most.
>
> Just what I'd do.
>
>
> --
> Larry
> 78 Royale w/500 Caddy
> Menomonie, WI.
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Gene,

Right shoulder rotator cuff repair. Op went well, 6 weeks in a sling followed by long physio program.

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces] On Behalf Of gene Fisher
Sent: Friday, February 9, 2018 12:06 AM
To: gmclist
Subject: Re: [GMCnet] Ford A426C vacuum pump issues

> Larry,
>
> I don't know where the pump was located on the Azure; however, here's
> where it is on the F-150
>
> https://www.youtube.com/watch?v=sxo2QVwbDkI
>
> Scroll in to 3:00 minutes.
>
> IIRC Dave Lenzi removed the horns and stuck his as high up in that area as
> possible; well above and to the right of the hood.
>
> From looking at your photos I see the vacuum hook up is at the bottom with
> the hose facing towards the booster. It appears that the
> exhaust was facing up; however, I can't tell that for sure. If it was I'd
> guess that's how the water got in to the pump.
>
> I mounted the one on The Blue Streak behind the bracket that Ken's
> electric windshield wipers mount to and I made a hood that
> extends over the exhaust filter.
>
> Unfortunately I can't provide any photos as I can't drive with my arm in a
> sling so I can't get to my workshop.
>

Sooo, what happened to your arm?.

> Regards,
> Rob M.
> The Pedantic Mechanic
> Sydney, Australia
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
> USA '77 Kingsley - TZE 267V100808
>
>
> -----Original Message-----
> From: Gmclist [mailto:gmclist-bounces] On Behalf Of Larry
> Sent: Thursday, February 8, 2018 2:40 PM
> To: gmclist
> Subject: [GMCnet] Ford A426C vacuum pump issues
>
> Several years ago I purchased a Ford Azure vacuum pump and installed it
> under the drivers side hatch on my coach. As you all know it
> is used in conjunction with the vacuum booster to provide braking vacuum
> in the event that the engine should quit. The pump has
> worked flawlessly until several weeks ago when it stopped pumping. It just
> blew 20 amp fuses. I took the thing off and disassembled
> it. I found the crankshaft inside corroded badly
> enough to seize the shaft so that the motor could not turn the crank. I
> soaked the crank with Kroil for about an hour and twisted it
> with a channel lock and eventually broke it loose. I was surprised at how
> much corrosion I found inside of the pump.
>
> Does anyone know where the pump was located on the Ford Azure?
> Considering the amount of corrosion inside the pump, I think that
> locating it under the hatch (as many of us have done) is no longer
> advisable. It needs to be located in a place that is less exposed
> to the elements. Any suggestions?
>
> If your pump is located under the hatch as in this picture
>
>
> http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p55693-img-10802.html
>
> I would advise pulling the filter off of the front of the pump and check
> to see if any corrosion has taken place. The filter
> housing is located
> opposite the electric motor in this picture.
>
>
> http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p55680-img-10841.html
>
> here:
>
>
> http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p64527-img-12381.html
>
> and here
>
>
> http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p64526-img-12371.html
>
>
> I'd hate to see this thing lock up on you all when you need it most.
>
> Just what I'd do.
>
>
> --
> Larry
> 78 Royale w/500 Caddy
> Menomonie, WI.
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://bdub.net/gmcmotorhome.info/
Alternator Protection Cable
http://bdub.net/gmcmotorhome.info/APC.html
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Larry,

Thanks for clarifying how you installed the exhaust, kinda figured you would have installed it as noted below.

I got to thinking about the filter and I reckon air goes in and out of it as the diaphragms displace air in the crankcase.

I think Dave got it right by removing the horns and tucking the pump up in that area as high as possible with the exhaust filter as
far away from the hood as possible.

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces] On Behalf Of Larry
Sent: Friday, February 9, 2018 1:56 AM
To: gmclist
Subject: Re: [GMCnet] Ford A426C vacuum pump issues

Rob,

When I installed the pump, I recognized the issue with the exhaust facing up, so took the time to remove the exhaust filter and turn
it so it was facing down. Also placed a piece of rubber conveyer belt material over the pump to deflect water that may get in
around the hatch. Obviously was not enough. I've let the pump crank soak overnight with Kroil and today I'm going to flush it out
in my parts cleaner. Then will coat the crank and
filter good with "Corrosion X"

https://www.amazon.com/Corrosion-X-90102-Anti-Corrosion-Lubricant-16-Ounce/dp/B003HFTI0S/ref=sr_1_1?ie=UTF8&qid=1518101178&sr=8-1&ke
ywords=corrosion-x

My son-in-law put me on to this stuff 4 or 5 yrs ago and it has eliminated misc. issues I've had with corrosion in coach and home.
I don't really want to move the pump so will also be pulling the exhaust/filter every year to check it. Just what I'm gonna do.
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
 
Rob -
Hope the healing continues well. Along those lines, you can't physically drive, or The Do - Rights will ticket you for doing so one armed (presumably
not if you're driving something one-arm equipped)? Here you gotta have a 'necker's knob' swivel on the steering wheel, power steering and brakes, and
automatic trans.

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
Larry,
It looks that you have mounted the pump in a location that allow the water
and road spray to drip onto the vacuum pump from the top of the door seam.
when I installed the vacuum pump in our first using a GM pump that everyone
was using at the time (no longer available) I put it in the location that
everyone was using at the time. I noticed after the first trip that water
had dripping on the pump. I put a drip shield over the pump to protect it
from it getting wet in the future and that pump was still working without
issue in 2011 (11 years) when we sold the coach.

First vacuum pump I used in 2000:
http://www.gmcmhphotos.com/photos/vacuum-pump-vacuum-switch/p1606.html
http://www.gmcmhphotos.com/photos/vacuum-pump-vacuum-switch/p1605.html
http://www.gmcmhphotos.com/photos/vacuum-pump-vacuum-switch/p1604.html

When we bought the stretch coach in 2011 it did not have a additional
vacuum pump other than a additional small vacuum tank. The Ford pump was
mounted (in 2013) as far back in the cavity as I could. It is an area that
stays dry and the picture is little misleading as it sits up high and
doesn’t get wet, While we are in Tucson the coach is in storage here in
the RV park and I will walk over and see if I can get any additional shots
that show the small vacuum tank and pump layout.

Ford A426C pump installed in the Buskirk stretch:
http://www.gmcmhphotos.com/photos/general-pictures/p59295-dl-brake-layout.html

Water has always been a problem as it comes off the windshield and leaks
into the compartment thru the door seam. A lot of GMC’ers have installed
water drip shields to direct the water away from the vacuum pump, master
cylinder and other under the cover items.

J.R. Wright
GMC GreatLakerTech Editor
78 Buskirk 30' Stretch
75 Avion Under Reconstruction
Michigan (On Location in Tucson)
 
As the pump seldom runs. Why not just mount it inside the coach where it will be dry and away from contaminated air.

--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
There used to be a marvel mystery oil top oil dispenser in common use. It
metered out an adjustable amount of marvel oil. If you could find one of
those oilers, and plumb it into your Azure pump, it might be just the
ticket.
Jim Hupy
Salem, Or
78 Royale 403

As the pump seldom runs. Why not just mount it inside the coach where it
will be dry and away from contaminated air.

--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

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> Water has always been a problem as it comes off the windshield and leaks
> into the compartment thru the door seam. A lot of GMC'ers have installed
> water drip shields to direct the water away from the vacuum pump, master
> cylinder and other under the cover items.
>
> J.R. Wright

JR,
Thanks for the comments, I just posted s pic of the drip shield that I have used to protect the vacuum pump. Just FYI

http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p64528-img-12401.html

--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
 
This is an area that I'm not up on. You want one of these types of pumps so that if your engine stops running suddenly while driving along. You'll still have power brakes working. I had this happen while driving someone's GMC. And this happening wasn't a surprise at that time. And there still was enough vacuum reserve in the booster. Stopped fine. Don't think a second stop would have had full boost. But the brakes still work without vacuum. Just has a very hard pedal. I'm a safety, and maintenance nut. OK. What am I missing here? Bob Dunahugh
 
You just think the brakes work without vacuum. Try it someday. Just make sure when you do the test that you have room to coast to a stop after
pressing on the brake pedal and that it is perfectly flat so you do not roll backwards after stopping. I'm glad my emergency / parking brake worked.

--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
Bob, I went with Mark K to pick up his new 73 coach in Pall Mall, Tenn. (home of Alvin York). Pall Mall is in a valley where access road is straight
up narrow 2 lane switchback steep mountain road with drop offs and no guard rails. Mark wanted me to drive and he spent a lot of time talking to PO
about the coach so it was almost dark before we got started back with Mark following in the truck. The coach had sat unused for a while and the
brakes were marginal. I got about half way up the mountain and the points closed up and engine died and was immediately rolling backwards.
Everything I had was on the brakes including e-brake pulled and no signs of stopping. I got it manovered backwards around the hairpin curve I was in
and into a very small wide spot that had some large rocks that had fallen from the cliff and got it crammed in park against a big rock. Mark had
flashers on blocking traffic and ran up to coach to tell me what a great job I had done. He found a Snow White figure sitting at the wheel with
fingers gripping a bent steering wheel. I did get the points reset and drove on home carefully with no more issues.

> This is an area that I'm not up on. You want one of these types of pumps so that if your engine stops running suddenly while driving along.
> You'll still have power brakes working. I had this happen while driving someone's GMC. And this happening wasn't a surprise at that time. And there
> still was enough vacuum reserve in the booster. Stopped fine. Don't think a second stop would have had full boost. But the brakes still work without
> vacuum. Just has a very hard pedal. I'm a safety, and maintenance nut. OK. What am I missing here? Bob Dunahugh
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--
C. Boyd
76 Crestmont
East Tennessee
 
I'd rather go for shorter hoses and less noie. Do the Chuck Master Cylinder thing and fit a plastic bottle over it.

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
> I'd rather go for shorter hoses and less noie. Do the Chuck Master Cylinder thing and fit a plastic bottle over it.
>
> --johnny

As I posted in the sub-thread, this is how I have shielded my pump from the elements.

http://www.gmcmhphotos.com/photos/emergency-vacuum-pump-for-power-brakes/p64528-img-12401.html

But ya know, if we are going down the road in heavy rain, everything under there is getting wet. No way to avoid it. We just need to do the best we
can to shield the pump from MOST of the elements. Then, I believe we need to pull that exhaust/filter off every year, just to make sure it's ok. JWIT
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
 
I was pulling Culowee Mountain when my 23' died - with the toad on back. I did manage to get it stopped before it went over the side, and the
following week fitted it with a vacuum reservoir and pump. I've one more foot than Chuck to stomp with, which probably made the difference. Bottom
line is, you do not want to give out of brake boost on a hill in your coach. It's usually luck which keeps you from bending something.

--johnny
--
76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
"I forgive them all, save those who hurt the dogs. They must answer to me in hell" - ol Andy, paraphrased
 
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