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

Home » Public Forums » GMCnet » Brake shoe adjustment
Brake shoe adjustment [message #322810] Mon, 28 August 2017 07:43 Go to next message
McCohens is currently offline  McCohens   United States
Messages: 22
Registered: March 2016
Location: Chalfont, PA
Karma: 0
Junior Member
Sorry for not searching this first. but I am headed to the driveway to replace all 4 sets of brake shoes on my 76 eleganza II. A leaking cylinder in one has prompted the work, and the wheels are off anyway for the new tires.
The manual says tighten adjusters until there is drag then back off 30 clicks. This seems like a lot, I was thinking more like just until there is no or very slight drag. Any small amount of drag would get worn off in the first few miles. BUT drum brake adjustment is a new thing for me, so please contribute to my education. Will check back later, should be a few hours to do all 4 wheels.
TIA
Randy
Re: Brake shoe adjustment [message #322811 is a reply to message #322810] Mon, 28 August 2017 07:50 Go to previous messageGo to next message
77Royale   United States
Messages: 461
Registered: June 2014
Location: Mid Michigan
Karma: 6
Senior Member
Id tighten until it starts to drag and back off a few clicks. While your in there, Id clean and pack each bearing if it hasn't been done in a while. Mobil 1 or Synpower.

The smaller (less friction material) of the two shoes goes FORWARD.


77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy. Mid Michigan
Re: Brake shoe adjustment [message #322815 is a reply to message #322810] Mon, 28 August 2017 08:19 Go to previous messageGo to next message
McCohens is currently offline  McCohens   United States
Messages: 22
Registered: March 2016
Location: Chalfont, PA
Karma: 0
Junior Member
Good call on the wheel bearings, now I need to order new seals and start my least favorite job of cleaning and packing 8 bearings!
Time to look up the seal number.
Re: Brake shoe adjustment [message #322817 is a reply to message #322810] Mon, 28 August 2017 08:21 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
Senior Member
There's a test for those seals. On a flat surface, you should be able to pass a drill bit (1/4"? Someone help me here) betwee nthe seal material and the surface. Sometimes you are given seals with the sealing face too close to the side of the seal away from the bearing. Those have problems sealing properly.

--johnny


Foolish Carriage, 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
Re: Brake shoe adjustment [message #322818 is a reply to message #322810] Mon, 28 August 2017 08:26 Go to previous messageGo to next message
77Royale   United States
Messages: 461
Registered: June 2014
Location: Mid Michigan
Karma: 6
Senior Member
SKF 21771 is the seal, I have found correct ones from Napa. (while your there pick up a bearing packer) That makes the job a bit better.

Yes, 1/4 inch drill bit or flat stock that will fit inside the inner part of the seal.



77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy. Mid Michigan
Re: Brake shoe adjustment [message #322819 is a reply to message #322810] Mon, 28 August 2017 08:34 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
Senior Member
Be sure you understand the wheel bearing adjustment sequence involving a torque wrench to seat and then the loosening, finger tightening and pinning procedure. A Lisle bearing bench greaser is a nice tool to have.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: Brake shoe adjustment [message #322821 is a reply to message #322810] Mon, 28 August 2017 08:37 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
Senior Member
Important is after finger tightening, if no holes line up, loosen to the next alternate hole do not tighten. Note where the holes are before nutting and how they alternate.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: Brake shoe adjustment [message #322822 is a reply to message #322815] Mon, 28 August 2017 08:53 Go to previous messageGo to next message
Bullitthead is currently offline  Bullitthead   United States
Messages: 1411
Registered: November 2013
Karma: 5
Senior Member
Put a spare wheel and tire on with a couple of nuts and get a helper to spin the wheel while you adjust if you can. With or without the helper, when properly adjusted the wheel will spin (freewheel)just less than 1 full turn after you stop trying to keep it spinning. Then go and apply the brake and release and check the free spin again. You will probably then get to adjust it up 3-5 clicks to get it just right. If they are new brake shoes, you will have to repeat this last adjustment after several stops. If your self-adjusters work properly, you shouldn't have to repeat the last adjustment if you back up and stop several times, hard enough to make them work.

Terry Kelpien ASE Master Technician 73 Glacier 260 Smithfield, Va.
Re: Brake shoe adjustment [message #322825 is a reply to message #322810] Mon, 28 August 2017 09:30 Go to previous messageGo to next message
McCohens is currently offline  McCohens   United States
Messages: 22
Registered: March 2016
Location: Chalfont, PA
Karma: 0
Junior Member
OK, go the packer and grease, mid cylinders and seals, but I think the seals are wrong. They don't carry SKF sold me National 8974S. The lip of the seal to the edge of the metal is .240 but the dimension from the lip to the flat side(outer) is .260
Are these OK or do I have to keep hunting. My parts guy, who is pretty good, said SKF 21771 is NLA. Maybe just for him though.
Shoes are new, so I am not too concerned about adjustment initially. They will need to bed to the drums and further adjustment is planned. Looking forward to being able to stop this beast.
Just did master cylinder and prop vales, new fuel lines and tires. After a 10 year nap we are getting close to hitting the road again. Maybe...
Re: [GMCnet] Brake shoe adjustment [message #322828 is a reply to message #322817] Mon, 28 August 2017 10:01 Go to previous messageGo to next message
bdub is currently offline  bdub   United States
Messages: 1578
Registered: February 2004
Location: Central Texas
Karma: 5
Senior Member


http://www.bdub.net/Seals,_Wheel_Bearings.pdf


-----Original Message-----
From: Gmclist On Behalf Of Johnny Bridges via Gmclist
Sent: Monday, August 28, 2017 8:22 AM

There's a test for those seals. On a flat surface, you should be able to
pass a drill bit (1/4"? Someone help me here) betwee nthe seal material and
the surface. Sometimes you are given seals with the sealing face too close
to the side of the seal away from the bearing. Those have problems
sealing properly.



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



bdub
'76 Palm Beach/Central Texas
www.bdub.net
www.gmcmhphotos.com
www.gmcmotorhomemarketplace.com
www.gmcmhregistry.com
www.facebook.com/groups/classicgmcmotorhomes
www.facebook.com/groups/gmcmm
Re: [GMCnet] Brake shoe adjustment [message #322829 is a reply to message #322825] Mon, 28 August 2017 10:07 Go to previous messageGo to next message
bdub is currently offline  bdub   United States
Messages: 1578
Registered: February 2004
Location: Central Texas
Karma: 5
Senior Member

If you'll order from Jim K., you'll get the correct parts.
http://appliedgmc.com/

-----Original Message-----
From: Gmclist On Behalf Of Randy Cohen/Catherine McGinley
OK, go the packer and grease, mid cylinders and seals, but I think the seals
are wrong. They don't carry SKF sold me National 8974S. The lip of the
seal to the edge of the metal is .240 but the dimension from the lip to the
flat side(outer) is .260
Are these OK or do I have to keep hunting. My parts guy, who is pretty
good, said SKF 21771 is NLA. Maybe just for him though.
Shoes are new, so I am not too concerned about adjustment initially. They
will need to bed to the drums and further adjustment is planned. Looking
forward to being able to stop this beast.
Just did master cylinder and prop vales, new fuel lines and tires. After a
10 year nap we are getting close to hitting the road again. Maybe...



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



bdub
'76 Palm Beach/Central Texas
www.bdub.net
www.gmcmhphotos.com
www.gmcmotorhomemarketplace.com
www.gmcmhregistry.com
www.facebook.com/groups/classicgmcmotorhomes
www.facebook.com/groups/gmcmm
Re: Brake shoe adjustment [message #322832 is a reply to message #322810] Mon, 28 August 2017 11:00 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
Senior Member
I got four seals from Advance, they had to order two of them. All four had the same number stamped in the metal part. First two were Federal, second two weren't. Only difference - the Federal ones had an orange sealer painted on the contact surface of the seal housing while the others didn't. Until I put some sealer on them as well.

--johnny


Foolish Carriage, 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
Re: Brake shoe adjustment [message #322834 is a reply to message #322832] Mon, 28 August 2017 11:26 Go to previous messageGo to next message
Harry is currently offline  Harry   Canada
Messages: 1888
Registered: October 2007
Location: Victoria, BC CANADA
Karma: 3
Senior Member
You can get all new springs too
Re: [GMCnet] Brake shoe adjustment [message #322835 is a reply to message #322817] Mon, 28 August 2017 11:57 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member
If you have the GMCMI Parts Interchange Index look in the front (about page 9). There is a good writeup on the front and rear seals that tells
how to make sure you have the right ones.

Emery Stora
77 Kingsley
Frederick, CO

> On Aug 28, 2017, at 7:21 AM, Johnny Bridges via Gmclist wrote:
>
> There's a test for those seals. On a flat surface, you should be able to pass a drill bit (1/4"? Someone help me here) between the seal material and
> the surface. Sometimes you are given seals with the sealing face too close to the side of the seal away from the bearing. Those have problems
> sealing properly.
>
> --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
>
>
> _______________________________________________
> 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: Brake shoe adjustment [message #322839 is a reply to message #322810] Mon, 28 August 2017 12:58 Go to previous messageGo to next message
McCohens is currently offline  McCohens   United States
Messages: 22
Registered: March 2016
Location: Chalfont, PA
Karma: 0
Junior Member
So it looks like the seals are wrong. Off to find the right ones.
Yes I would normally order from Applied, but want this done today so I need to get them locally.

One side complete, wheel cylinders were shot and ruined the shoes. Also think a seal might be failing but with all the brake fluid in the drum it is hard to tell what failed.

Re: Brake shoe adjustment [message #322849 is a reply to message #322810] Mon, 28 August 2017 14:50 Go to previous messageGo to next message
77Royale   United States
Messages: 461
Registered: June 2014
Location: Mid Michigan
Karma: 6
Senior Member
Since your already into the wheel cylinders, take a moment to put a few careful wraps of teflon tape on the bleeder screws. You will thank yourself for it then next time you have to bleed the system.. (and cudos to Matt C for passing the info on)



77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy. Mid Michigan
Re: [GMCnet] Brake shoe adjustment [message #322855 is a reply to message #322825] Mon, 28 August 2017 15:10 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Randy,

Here you go:

http://www.gmcmhphotos.com/photos/rear-axle-seals-skf21771/p36356-says-made-in-the-usa.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@list.gmcnet.org] On Behalf Of Randy Cohen/Catherine McGinley
Sent: Tuesday, August 29, 2017 12:30 AM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Brake shoe adjustment

OK, go the packer and grease, mid cylinders and seals, but I think the seals are wrong. They don't carry SKF sold me National
8974S. The lip of the
seal to the edge of the metal is .240 but the dimension from the lip to the flat side(outer) is .260
Are these OK or do I have to keep hunting. My parts guy, who is pretty good, said SKF 21771 is NLA. Maybe just for him though.
Shoes are new, so I am not too concerned about adjustment initially. They will need to bed to the drums and further adjustment is
planned. Looking
forward to being able to stop this beast.
Just did master cylinder and prop vales, new fuel lines and tires. After a 10 year nap we are getting close to hitting the road
again. Maybe...

_______________________________________________
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] Brake shoe adjustment [message #322856 is a reply to message #322825] Mon, 28 August 2017 15:18 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Randy,

I just thought of something that no one has mentioned, the rear brake shoes adjust themselves automatically whenever you backup and
hit the brakes. You could go to a large parking lot and back up and stop repeatedly until they're adjusted.

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@list.gmcnet.org] On Behalf Of Randy Cohen/Catherine McGinley
Sent: Tuesday, August 29, 2017 12:30 AM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Brake shoe adjustment

OK, go the packer and grease, mid cylinders and seals, but I think the seals are wrong. They don't carry SKF sold me National
8974S. The lip of the
seal to the edge of the metal is .240 but the dimension from the lip to the flat side(outer) is .260
Are these OK or do I have to keep hunting. My parts guy, who is pretty good, said SKF 21771 is NLA. Maybe just for him though.
Shoes are new, so I am not too concerned about adjustment initially. They will need to bed to the drums and further adjustment is
planned. Looking
forward to being able to stop this beast.
Just did master cylinder and prop vales, new fuel lines and tires. After a 10 year nap we are getting close to hitting the road
again. Maybe...

_______________________________________________
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] Brake shoe adjustment [message #322889 is a reply to message #322856] Mon, 28 August 2017 21:45 Go to previous messageGo to next message
johnd01 is currently offline  johnd01   United States
Messages: 354
Registered: July 2017
Location: Sacrameot
Karma: -1
Senior Member
That is if it still works.

On Mon, Aug 28, 2017 at 1:18 PM, Rob Mueller
wrote:

> Randy,
>
> I just thought of something that no one has mentioned, the rear brake
> shoes adjust themselves automatically whenever you backup and
> hit the brakes. You could go to a large parking lot and back up and stop
> repeatedly until they're adjusted.
>
> 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@list.gmcnet.org] On Behalf Of Randy
> Cohen/Catherine McGinley
> Sent: Tuesday, August 29, 2017 12:30 AM
> To: gmclist@list.gmcnet.org
> Subject: Re: [GMCnet] Brake shoe adjustment
>
> OK, go the packer and grease, mid cylinders and seals, but I think the
> seals are wrong. They don't carry SKF sold me National
> 8974S. The lip of the
> seal to the edge of the metal is .240 but the dimension from the lip to
> the flat side(outer) is .260
> Are these OK or do I have to keep hunting. My parts guy, who is pretty
> good, said SKF 21771 is NLA. Maybe just for him though.
> Shoes are new, so I am not too concerned about adjustment initially. They
> will need to bed to the drums and further adjustment is
> planned. Looking
> forward to being able to stop this beast.
> Just did master cylinder and prop vales, new fuel lines and tires. After
> a 10 year nap we are getting close to hitting the road
> again. Maybe...
>
> _______________________________________________
> 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
>



--

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



Johnd01 John Phillips Avion A2600 TZE064V101164 Rancho Cordova, CA (Sacramento)
Re: [GMCnet] Brake shoe adjustment [message #322892 is a reply to message #322856] Mon, 28 August 2017 22:09 Go to previous messageGo to previous message
Bullitthead is currently offline  Bullitthead   United States
Messages: 1411
Registered: November 2013
Karma: 5
Senior Member
Rob, he wanted the initial setup after rebuilding the brakes, according to the original post.

No one


Terry Kelpien ASE Master Technician 73 Glacier 260 Smithfield, Va.
Previous Topic: [GMCnet] Black and Grey water tank reading
Next Topic: [GMCnet] Houston Floods
Goto Forum:
  


Current Time: Thu Mar 28 23:42:56 CDT 2024

Total time taken to generate the page: 0.01307 seconds