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80 mL Caliper Conversion Specifics [message #351022] Sat, 28 December 2019 20:47 Go to next message
uprooted is currently offline  uprooted   United States
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Location: Hilliard, OH
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I've got the calipers ground down and installed, and the rubber hoses test-fitted, but can't decide exactly how to bend the metal part of the lines to get them to work. When I look at the write up here https://www.gmcmotorhome.com/commodore/front_brake/index.html, It LOOKS like they bent the lines so that the banjo fitting is at a 90 degree angle from where it began. Can anyone confirm this and/or provide better or more specific photos?

Thanks in advance


Corey P / Hilliard, OH / 1974 Glacier 26' / 3.70 FD / ION Wheels
Re: 80 mL Caliper Conversion Specifics [message #351023 is a reply to message #351022] Sat, 28 December 2019 21:17 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Corey,

It has been many years since I did this conversion but I can guarantee you that I did not bend the lines 90 degrees. If I bent them at all, it was only slightly.

Do you possibly have the lines on the wrong sides? (Passenger vs. driver's side).

If you are talking about 90 degrees rotational when installing the banjo bolt, as I remember there is a nub on the cylinder that only allows you to install them in a certain orientation. Do you possibly have the calipers reversed? (passenger vs. Driver's side)

Sorry, It has been 15 years and I do not remember much about this, and I am not near my coach right now to go look.

Ken B.

Go Clemson


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] 80 mL Caliper Conversion Specifics [message #351025 is a reply to message #351023] Sat, 28 December 2019 21:22 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Location: Belmont, CA
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Senior Member
The correct hose has combinsyy to ion steel and rubber. There it left and
right

On Sat, Dec 28, 2019 at 7:17 PM Ken Burton via Gmclist <
gmclist@list.gmcnet.org> wrote:

> Corey,
>
> It has been many years since I did this conversion but I can guarantee you
> that I did not bend the lines 90 degrees. If I bent them at all, it was
> only slightly.
>
> Do you possibly have the lines on the wrong sides? (Passenger vs.
> driver's side).
>
> If you are talking about 90 degrees rotational when installing the banjo
> bolt, as I remember there is a nub on the cylinder that only allows you to
> install them in a certain orientation. Do you possibly have the calipers
> reversed? (passenger vs. Driver's side)
>
> Sorry, It has been 15 years and I do not remember much about this, and I
> am not near my coach right now to go look.
>
> Ken B.
>
> Go Clemson
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmcrvparts.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] 80 mL Caliper Conversion Specifics [message #351026 is a reply to message #351025] Sat, 28 December 2019 21:23 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Registered: July 2006
Location: Belmont, CA
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Senior Member
Sorry, it is composed of steel and rubber left and right.

On Sat, Dec 28, 2019 at 7:22 PM Jim Kanomata wrote:

> The correct hose has combinsyy to ion steel and rubber. There it left and
> right
>
> On Sat, Dec 28, 2019 at 7:17 PM Ken Burton via Gmclist gmclist@list.gmcnet.org> wrote:
>
>> Corey,
>>
>> It has been many years since I did this conversion but I can guarantee
>> you that I did not bend the lines 90 degrees. If I bent them at all, it was
>> only slightly.
>>
>> Do you possibly have the lines on the wrong sides? (Passenger vs.
>> driver's side).
>>
>> If you are talking about 90 degrees rotational when installing the banjo
>> bolt, as I remember there is a nub on the cylinder that only allows you to
>> install them in a certain orientation. Do you possibly have the calipers
>> reversed? (passenger vs. Driver's side)
>>
>> Sorry, It has been 15 years and I do not remember much about this, and I
>> am not near my coach right now to go look.
>>
>> Ken B.
>>
>> Go Clemson
>> --
>> Ken Burton - N9KB
>> 76 Palm Beach
>> Hebron, Indiana
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk@appliedairfilters.com
> http://www.appliedgmcrvparts.com
> 1-800-752-7502
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmcrvparts.com
1-800-752-7502
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GMCnet mailing list
Unsubscribe or Change List Options:
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: 80 mL Caliper Conversion Specifics [message #351029 is a reply to message #351022] Sat, 28 December 2019 22:09 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Location: St. Cloud, MN
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Senior Member
After thinking about it too much..... final answer was
To just get the lines where they need to be on the coach and it is easy to see how you need to bend them.

The biggest thing is how to mount the bracket to the a-arm and route the line. Just get in there and fit it up and you will see what has to happen. Small bend- maybe two trips back to the vice and back to re-fit to coach.


Make sure you file the casting edge on the knuckle itself. That is not documented well. The round part
Of the knuckle where the caliper sits, needs a little filing to clean up the casting. Caliper can rub there(was rubbing on a coach we did not do that to)


Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: 80 mL Caliper Conversion Specifics [message #351030 is a reply to message #351022] Sat, 28 December 2019 23:12 Go to previous messageGo to next message
uprooted is currently offline  uprooted   United States
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Registered: December 2019
Location: Hilliard, OH
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Member
The calipers are on the correct side (bleeder is up), and the casting nub is ground off. Here are some photos of how the line interferes with the ball joint stud and cv joint currently. I am ready to take the "get in there and see what way it needs to go" approach but I was wondering if anyone had any photos of exactly how theirs is bent. I want to learn from others mistakes / successes.

http://www.gmcmhphotos.com/photos/data/7264/medium/Capture2.JPG

http://www.gmcmhphotos.com/photos/data/7264/medium/Capture3.JPG

http://www.gmcmhphotos.com/photos/data/7264/medium/Capture1.JPG


Corey P / Hilliard, OH / 1974 Glacier 26' / 3.70 FD / ION Wheels
Re: 80 mL Caliper Conversion Specifics [message #351032 is a reply to message #351022] Sun, 29 December 2019 07:44 Go to previous messageGo to next message
6cuda6 is currently offline  6cuda6   Canada
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I dont personally like bending prefab lines but if one must i would mount the line on the caliper, and carefully/limitedly bend the line to just clear what i need it too.....in my opinion you risk kinking the line if you try to get to gready with it.

One thing to keep in mind is you just need enough room to clear the ball joint nut...i wouldnt care if i had to remove the caliper to put the nut on or remove it.

Do the bend by hand, do not use plyers or the like....its probly not possible but if you could get a bending spring over the line it would help keep it from kinking...

Take your time and it might just work out.....YMMV and proceed at your own risk.


Rich Mondor, Brockville, ON 77 Hughes 2600
Re: 80 mL Caliper Conversion Specifics [message #351037 is a reply to message #351022] Sun, 29 December 2019 08:30 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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What the pics show is totally different from what I have, I reversed the banjos. However, after looking, I'm going back and refitting them. I borrowed Zhookoff's pressure bleeder but it leaks at the seal. Inspection shows the rubber is creased here and there where it hits the edge of the master cylinder. A new rubber mat is in the offing tomorrow. Meantimes, I can run clear fluid forever out of the caliper bleed nipples, but no pedal. I suspect air in the master cylinder bores. Can the MC be bled on the coach? Take the lines off and fit the return tubes and pump till the bubbles if any go away? It's level, due to the front wheels are off and the cribbing is a bit low.

--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: 80 mL Caliper Conversion Specifics [message #351038 is a reply to message #351037] Sun, 29 December 2019 08:44 Go to previous messageGo to next message
6cuda6 is currently offline  6cuda6   Canada
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Yes it can....same way as a caliper....pump it up, hold pedal, open line....repeat on piston #2..then pump it up, hold etc...dont take the lines off or youll have air in the rest of the system.

Once you get a bit of a pedal move to bleeding the brakes....i always start the furthest away from the master, then opposing front, opposing back etc.....X pattern if possible to keep the propprtioning valve somewhat centered.

Johnny Bridges wrote on Sun, 29 December 2019 09:30
What the pics show is totally different from what I have, I reversed the banjos. However, after looking, I'm going back and refitting them. I borrowed Zhookoff's pressure bleeder but it leaks at the seal. Inspection shows the rubber is creased here and there where it hits the edge of the master cylinder. A new rubber mat is in the offing tomorrow. Meantimes, I can run clear fluid forever out of the caliper bleed nipples, but no pedal. I suspect air in the master cylinder bores. Can the MC be bled on the coach? Take the lines off and fit the return tubes and pump till the bubbles if any go away? It's level, due to the front wheels are off and the cribbing is a bit low.

--johnny


Rich Mondor, Brockville, ON 77 Hughes 2600
Re: 80 mL Caliper Conversion Specifics [message #351069 is a reply to message #351037] Mon, 30 December 2019 08:39 Go to previous message
Matt Colie is currently offline  Matt Colie   United States
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Johnny Bridges wrote on Sun, 29 December 2019 09:30
<snip>
I suspect air in the master cylinder bores. Can the MC be bled on the coach? Take the lines off and fit the return tubes and pump till the bubbles if any go away? It's level, due to the front wheels are off and the cribbing is a bit low.

--johnny
Yes, it can. We(I) did this for my friend Greg last fall when we changed out his master cylinder because at least one seal had gone out. We were able to remove the old one, "bench bleed" the new one in place, and then carefully bleed the line at the master and he got pretty good brakes back right away.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
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