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  #1  
Old 04-09-2017, 05:53 PM
PG13 PG13 is offline
 
Join Date: Apr 2017
Location: Fresno
Posts: 11
Default Brake line at wheel / rubbing- How to retain?

I just purchased my first RV. Right side brake pedals had just been installed. Noticed brakes dragging when flying from right which led to diagnosing. I noticed loose backing plates/(Pant retaining bracket?) on both sides which led me to remove wheel pants. Found a bent backing plate, & the disk rubbing it, also, lines just sitting there & one rubbing the disk. Is there some reason there isn't any kind of line retention to the backing plate to prevent rubbing or drooping as in my case? I'd like to secure the lines, at least loosley? How have others with flexible lines secured this?
(The dragging/applied brakes was caused by the pedals binding slightly & not releasing all master cyl pressure). How "hosed" am I with the condition of the backing plate, line, pads, etc? Also, all three bolts/nuts were loose that hold on the pant bracket. Suggestions?
600 hours on airframe.



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  #2  
Old 04-09-2017, 06:57 PM
YellowJacket RV9 YellowJacket RV9 is offline
 
Join Date: Oct 2012
Location: Clearwater, FL / KZPH
Posts: 961
Default

These lines look too long to me. Perhaps the builder used off the shelf lines and just made them work. With flexible lines like that there is no need for that much excess. If it were me I would buy or build new lines of the proper length and replace. It would be a fairly straightforward replacement, just requiring a brake bleed afterwards.

With regards to the other issues, the binding brakes can be helped with return springs, either on the master cylinders or brake pedals (my choice), as well as possibly going to one long bolt for each pedal to pivot on as opposed to two smaller ones. A quick search on here for sticking brakes or similar will yield a bunch of good ideas.

Chris
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Last edited by YellowJacket RV9 : 04-09-2017 at 07:33 PM.
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  #3  
Old 04-09-2017, 07:16 PM
BillSchlatterer BillSchlatterer is offline
 
Join Date: Jan 2005
Location: Arkansas
Posts: 453
Default Bonaco

Bonaco.... I hope that's right...it's been a while makes premade custom SS Shielded brake likes for all the RVs and they are really nice. As I remember it, all they needed to know what the type of RV and they had a kit already made up. Hooked them up and they were perfect. Seems like I ordered a kit on Monday and had them to put on that weekend.

Bill
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  #4  
Old 04-12-2017, 03:55 PM
PG13 PG13 is offline
 
Join Date: Apr 2017
Location: Fresno
Posts: 11
Default

Thanks guys. Yeah, I keep seeing 36" lines being mentioned here for the 7a. I guess I'll see how long mine are and order the correct ones.. and whether a 3 or a 4- which means nothing to me as of now, but I"m sure more research will yield the answer.
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  #5  
Old 04-12-2017, 05:28 PM
BillL BillL is offline
 
Join Date: Sep 2007
Location: Central IL
Posts: 3,870
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This looks like a sam james bracket. It may have been bent to match the pant. It is too close to the disc - it should not be touching. You can add a washer .063 or .031 to the spacer to help that clearance. You may need longer bolts to ensure function of the self-locking feature.

The brake hose could have slid down the gear. You may be able to just pull it up and properly secure so it won't touch anything moving or sharp, but allows some movement. Self vulcanizing silicone rescue tape works well to protect the gear leg and hold a hose or tube.

You got my comment on the bolt. A bear to do under the panel, but get several old pillows and get comfy. If you choose springs, just slide over the master cylinder plunger and set some preload with the stop collar. Bleed the brakes from the bottom up, not top down.

In all of this, one thing leads to another, so follow the issues generated as you correct the other for a successful outcome.

Happy repairs . . .Welcome to VAF!
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Last edited by BillL : 04-12-2017 at 05:31 PM.
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  #6  
Old 04-13-2017, 06:46 AM
olyolson's Avatar
olyolson olyolson is offline
 
Join Date: Dec 2009
Location: St Louis, MO
Posts: 600
Default Brake line

Tony,

I concur with Chris, your brake line looks too long to me. Since it has been rubbing it might not be a bad idea to replace it anyway. If the brake lines look OK you could take the gear leg fairings off, clean & inspect everything and as another poster said maybe you can slide the brake lines up and secure them toward the top of the gear legs. But with vibration they may slide back down eventually so replacement might be a good call.

I would further investigate why your pedals are binding. I just replaced my brake master cylinders and was going to reinstall the springs from the old cylinders but after talking to the techs at Matco they stressed NOT to use springs on the master cylinders. They said that is what used to be done until a lot of master cylinders started scoring from the springs and then started leaking- exactly what mine did. I did not reinstall springs on either side.

Isn't it fun doing your own maintenance?
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  #7  
Old 04-15-2017, 01:41 PM
PG13 PG13 is offline
 
Join Date: Apr 2017
Location: Fresno
Posts: 11
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Thanks again!
Yeah! Super fun doing my own mx.. I just hadn't anticipated starting on it literally the day I pulled it in to my hangar. I purchased the thin nylon sleeve bearings for both end of the springs (McMaster-Carr) to avoid contacting the rod and spring issue. I couldn't imagine that being a good idea either. Some of the photos I see here were a tad concerning to me about longevity.
I have the 2 bolt setup, but I have them really operating freely.
Hadn't considered just taping the lines up in place. Hmmm.. I think the "rub" is superficial so I may do that, just to see how the rest of the mods/fixes go, and then tackle the inside-the-pant part when I replace the disks next inspection. The pads look cooked to me but my IA buddy says they are fine. But a line replacement seems in order.
The left side doesn't rub the disk. I think the right is bent. May pull it off to true it up or maybe just "tweak" it back in place.
Just one thing at a time. I haven't even made my first "payment" on it yet!
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