GMCforum
For enthusiast of the Classic GMC Motorhome built from 1973 to 1978. A web-based mirror of the GMCnet mailing list.

Home » GMC » GMCnet » Leigh Harrison Brake Rotor (Seeking to ID the Leigh Harrison Brake Rotors)
Re: Leigh Harrison Brake Rotor [message #326638 is a reply to message #325873] Sat, 02 December 2017 10:06 Go to previous messageGo to next message
Wackster is currently offline  Wackster   United States
Messages: 17
Registered: November 2017
Location: Baltimore
Karma: 0
Junior Member
Thanks for all of your responses, warm welcomes and participation in this amazing resource. Leigh Harrison brake service quickly evolved into a caliper replacement. With the calipers removed, it seemed foolish not to pull the hubs and visually inspect grease and bearing condition. Grease was good, but pitting on one bearing race and not knowing bearing age/service history led me to baseline both driver and passenger hubs with new Timken inner & outer bearings and races. I documented the outcome and parts used in photos here:

http://www.gmcmhphotos.com/photos/g7122-leigh-harrison-rear-brake-maintenance.html

Advice from older forum entries related to power bleeding the brakes led me to purchase a $71 kit from Motive. A virtually identical setup can be obtained from Jim Hupy: http://www.bdub.net/jhupy/. The power bleed approach strikes me as a no-brainer considering the alternative (enlisting my significant other for pedal pumping duty). Some other benefits I gleaned from prior forum entries on the subject:
1. Avoidance of potential master brake cylinder seal damage from extending the master cylinder beyond its normal travel.
2. Ability to perform the entire task with one person and with certainty that old fluid and air are expelled.

Thank you all again for your input and support.


Wackster - 1976 23' Crestmont Baltimore, Maryland
Re: [GMCnet] Leigh Harrison Brake Rotor [message #326670 is a reply to message #326638] Sun, 03 December 2017 08:10 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15505
Registered: July 2007
Location: Sydney, Australia
Karma: 42
Senior Member
James,

You may be disappointed with the Motive brake bleeder as the adapter that goes on the M/C is made of plastic and from photos it
appears the fluid feed tube goes through the top of that adapter. I don't believe there is enough space above the M/C for that tube
in the vertical position. You may be able to put a 90 degree fitting in there; however, my experience with those plastic adapters is
not good; they leak.

Jim's adapter is made of THICK aluminum plate and doesn't leak. He has made a change in the kit, he no longer uses chains; he uses
cable now. I have one of his kits in Houston and one in Sydney and they work GREAT!

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-AT-list-DOT-gmcnet-DOT-org] On Behalf Of James Wack
Sent: Saturday, December 2, 2017 10:06 AM
To: gmclist-AT-list-DOT-gmcnet-DOT-org
Subject: Re: [GMCnet] Leigh Harrison Brake Rotor

Thanks for all of your responses, warm welcomes and participation in this amazing resource. Leigh Harrison brake service quickly
evolved into a
caliper replacement. With the calipers removed, it seemed foolish not to pull the hubs and visually inspect grease and bearing
condition. Grease was
good, but pitting on one bearing race and not knowing bearing age/service history led me to baseline both driver and passenger hubs
with new Timken
inner & outer bearings and races. I documented the outcome and parts used in photos here:

http://www.gmcmhphotos.com/photos/g7122-leigh-harrison-rear-brake-maintenance.html

Advice from older forum entries related to power bleeding the brakes led me to purchase a $71 kit from Motive. A virtually
identical setup can be
obtained from Jim Hupy: http://www.bdub.net/jhupy/

. The power bleed approach strikes me as a no-brainer considering the alternative (enlisting my
significant other for pedal pumping duty). Some other benefits I gleaned from prior forum entries on the subject:
1. Avoidance of potential master brake cylinder seal damage from extending the master cylinder beyond its normal travel.
2. Ability to perform the entire task with one person and with certainty that old fluid and air are expelled.

Thank you all again for your input and support.

--
Wackster - 1976 23' Crestmont
Baltimore, Maryland

_______________________________________________
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



Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Leigh Harrison Brake Rotor [message #326709 is a reply to message #326670] Sun, 03 December 2017 19:36 Go to previous messageGo to next message
Wackster is currently offline  Wackster   United States
Messages: 17
Registered: November 2017
Location: Baltimore
Karma: 0
Junior Member
Rob,

So far so good with the Motive adapter (https://www.motiveproducts.com/collections/adapters/products/1105-rectangular-early-american-adapter). It is a solid AL plate with a thicker section down the middle that is drilled and tapped to provide the fluid path for the forward and rear reservoirs. That said, I imagine Jim Hupy's cables would definitely be an improvement over the chains. I got it all to work, but getting even tension on the hold-down's was awkward. Of course it doesn't help that my PO installed "Brake-Guards" that interfere with the hold-down arrangement of either product. I intend to try making my own adapter from an aftermarket replacement master cylinder cover. It would be so much easier to snap the bales over a stock cover with inlet ports for pressure bleeding than fuss with the AL adapter and hold downs.


Wackster - 1976 23' Crestmont Baltimore, Maryland
Re: [GMCnet] Leigh Harrison Brake Rotor [message #326710 is a reply to message #326709] Sun, 03 December 2017 20:07 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15505
Registered: July 2007
Location: Sydney, Australia
Karma: 42
Senior Member
James,

I had never seen the metal flat plate before the ones I saw all had plastic flat plates that leaked.

You could make your own cables from parts available locally.

We have discussed those "Brake-Guards" here on a number occasions and the conclusion has been SNAKE OIL.

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-AT-list-DOT-gmcnet-DOT-org] On Behalf Of James Wack
Sent: Sunday, December 3, 2017 7:37 PM
To: gmclist-AT-list-DOT-gmcnet-DOT-org
Subject: Re: [GMCnet] Leigh Harrison Brake Rotor

Rob,

So far so good with the Motive adapter
(https://www.motiveproducts.com/collections/adapters/products/1105-rectangular-early-american-adapter). It is a solid AL plate with
a thicker section down the middle that is drilled and tapped to provide the fluid path for the forward and rear reservoirs.
That said, I imagine Jim Hupy's cables would definitely be an improvement over the chains. I got it all to work, but getting even
tension on the hold-down's was awkward. Of course it doesn't help that my PO installed "Brake-Guards" that interfere with the
hold-down arrangement of either product. I intend to try making my own adapter from an aftermarket replacement master cylinder
cover. It would be so much easier to snap the bales
over a stock cover with inlet ports for pressure bleeding than fuss with the AL adapter and hold downs.
--
Wackster - 1976 23' Crestmont
Baltimore, Maryland



_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org



Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Leigh Harrison Brake Rotor [message #326711 is a reply to message #326710] Sun, 03 December 2017 21:48 Go to previous messageGo to next message
Wackster is currently offline  Wackster   United States
Messages: 17
Registered: November 2017
Location: Baltimore
Karma: 0
Junior Member
Rob,

Miguel at MGM GMC looked the coach over before I attempted the drive to Maryland. He had a similar opinion regarding the Brake Guards - worse actually, he thought they may result in a fractionally increased brake response time. They will come off, maybe this maintenance cycle. As far as the cables - yes, I have access to a swaging tool and will make some up. I would have finished up the bleeding this afternoon but was a little shortsighted and only purchased 1 qt of DOT 4 brake fluid. Not sure what the community thinks about DOT 3 vs. 4, but I was committed to the better rating considering all the other time and expense I put into the effort.


Wackster - 1976 23' Crestmont Baltimore, Maryland
Re: [GMCnet] Leigh Harrison Brake Rotor [message #326712 is a reply to message #326711] Sun, 03 December 2017 23:42 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4195
Registered: January 2004
Karma: 9
Senior Member
Why do you feel that DOT 4 is the better rating?

There are differences besides boiling point such as viscosity and anti corrosion.

Problem is that under certain circumstances DOT-4 doesn't last as long; it absorbs moisture faster than DOT-3 and will sometimes have a lower boiling point in 6-months. So count on replacing DOT-4 fluid that often to keep it "better" than DOT-3.

Do not assume that DOT 4 will necessarily be better for your system than DOT 3. There is a reason that DOT 3 is specified for a number of cars. For one the compatibility of the specific rubber types used for components chosen to be in that car's system has been tested using DOT 3 by the braking engineers. Since I keep my vehicles a very long time I would want to know more about whether putting in DOT 4 is the best for a particular system.

There are reasons that DOT 3 is still on the market. If the Department of Transportation felt DOT 4 were “better” why would they still allow DOT 3 to be sold.?

It is not simple to just say one is better. Depending on conditions of use and the system it is in there are times when one could say that DOT 3 is “better”..

Emery Stora
77 Kingsley
Frederick, CO

> On Dec 3, 2017, at 8:48 PM, James Wack wrote:
>
> Rob,
>
> Miguel at MGM GMC looked the coach over before I attempted the drive to Maryland. He had a similar opinion regarding the Brake Guards - worse
> actually, he thought they may result in a fractionally increased brake response time. They will come off, maybe this maintenance cycle. As far as
> the cables - yes, I have access to a swaging tool and will make some up. I would have finished up the bleeding this afternoon but was a little
> shortsighted and only purchased 1 qt of DOT 4 brake fluid. Not sure what the community thinks about DOT 3 vs. 4, but I was committed to the better
> rating considering all the other time and expense I put into the effort.
> --
> Wackster - 1976 23' Crestmont
> Baltimore, Maryland
>
> _______________________________________________
> 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
Re: [GMCnet] Leigh Harrison Brake Rotor [message #326716 is a reply to message #326711] Mon, 04 December 2017 07:35 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15505
Registered: July 2007
Location: Sydney, Australia
Karma: 42
Senior Member
James,

After researching the various brands of brake fluid here's what I use:

http://www.gmcmhphotos.com/photos/aa-miscellaneous-photos/p41972-ate-brake-fluid.html

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-AT-list-DOT-gmcnet-DOT-org] On Behalf Of James Wack
Sent: Sunday, December 3, 2017 9:48 PM
To: gmclist-AT-list-DOT-gmcnet-DOT-org
Subject: Re: [GMCnet] Leigh Harrison Brake Rotor

Rob,

Miguel at MGM GMC looked the coach over before I attempted the drive to Maryland. He had a similar opinion regarding the Brake
Guards - worse actually, he thought they may result in a fractionally increased brake response time. They will come off, maybe this
maintenance cycle. As far as the cables - yes, I have access to a swaging tool and will make some up. I would have finished up the
bleeding this afternoon but was a little
shortsighted and only purchased 1 qt of DOT 4 brake fluid. Not sure what the community thinks about DOT 3 vs. 4, but I was
committed to the better rating considering all the other time and expense I put into the effort.
--
Wackster - 1976 23' Crestmont
Baltimore, Maryland

_______________________________________________
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



Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Leigh Harrison Brake Rotor [message #326757 is a reply to message #326716] Tue, 05 December 2017 11:12 Go to previous messageGo to next message
Wackster is currently offline  Wackster   United States
Messages: 17
Registered: November 2017
Location: Baltimore
Karma: 0
Junior Member
Thanks Rob,

I had seen this product in conjunction with various YouTube video on power bleeding. I thought the concept of alternating colored fluid was quite clever and am somewhat surprised that colored brake fluid seems unique to the ATE product line. Guess I'll add 2 quarts of (unopened) brake fluid to my growing list of shelf-stock for GMC maintenance. Might need more shelves.


Wackster - 1976 23' Crestmont Baltimore, Maryland
Re: [GMCnet] Leigh Harrison Brake Rotor [message #326771 is a reply to message #326757] Tue, 05 December 2017 18:46 Go to previous message
USAussie is currently offline  USAussie   United States
Messages: 15505
Registered: July 2007
Location: Sydney, Australia
Karma: 42
Senior Member
James,

As noted on the Photo Site the Blue fluid is no longer available.

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-AT-list-DOT-gmcnet-DOT-org] On Behalf Of James Wack
Sent: Tuesday, December 5, 2017 11:12 AM
To: gmclist-AT-list-DOT-gmcnet-DOT-org
Subject: Re: [GMCnet] Leigh Harrison Brake Rotor

Thanks Rob,

I had seen this product in conjunction with various YouTube video on power bleeding. I thought the concept of alternating colored
fluid was quite
clever and am somewhat surprised that colored brake fluid seems unique to the ATE product line. Guess I'll add 2 quarts of
(unopened) brake fluid to
my growing list of shelf-stock for GMC maintenance. Might need more shelves.
--
Wackster - 1976 23' Crestmont
Baltimore, Maryland

_______________________________________________
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



Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Previous Topic: [GMCnet] Tankless hot water heater
Next Topic: Note for those with fueling issues (like Rod & John)
Goto Forum:
  


Current Time: Sun Dec 17 04:07:50 CST 2017

Total time taken to generate the page: 4.53333 seconds