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  #1  
Old 09-14-2021, 06:18 PM
fr0gpil0t fr0gpil0t is offline
 
Join Date: Apr 2013
Location: Colorado Springs
Posts: 74
Default Gun drilled gear - leaking brake fitting

The new gun drilled gear are great but I'm really struggling to get the one AN fitting to seal. A right angle elbow AN fitting screws into the base of the gear leg. It turns about 4 and a bit turns before bottoming out. I have to back the "bit of a turn" off so it is clocked correctly.

I've tried Permatex thread sealant, Permatex #2 and Loctite 567 and a new fitting but it always leaks ;-( No problems on the other leg.

I'm using a std 6in wrench to tighten the AN fitting - I could use something with more leverage but I really don't want to shear the AN fitting off.

I understand the principal of an NPT thread but wondering how I solve this issue. Tap out the thread a little so I can get the AN fitting to go in further ? Use a steel AN fitting - as the gear leg is steel.

Help please

Robert
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  #2  
Old 09-14-2021, 10:25 PM
6ato14a 6ato14a is offline
 
Join Date: Jan 2016
Location: longmont, co
Posts: 188
Default Earll’s plumbing

Check out Earl’s plumbing part number 923104erl or 923016erl. They are expensive but have a swivel on the pipe thread. Might work.
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  #3  
Old 09-15-2021, 02:54 AM
Taltruda Taltruda is offline
 
Join Date: Oct 2017
Location: Las Vegas, NV
Posts: 918
Default

I would consider Teflon tape on stubborn leaky fittings. If you can, perhaps run a pipe tap deeper so you don’t have to back off the fitting to clock it.
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  #4  
Old 09-15-2021, 01:06 PM
Bob Y Bob Y is offline
 
Join Date: Jul 2017
Location: Piedmont, SC
Posts: 300
Default

Quote:
Originally Posted by fr0gpil0t View Post
… Use a steel AN fitting - as the gear leg is steel.

Help please

Robert
My gun-drilled gear legs are tempered aluminum, not steel.
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  #5  
Old 09-15-2021, 02:15 PM
jrs14855 jrs14855 is offline
 
Join Date: Apr 2008
Location: Lake Havasu City AZ
Posts: 2,640
Default Fitting

One possible cause of the problem is that once there has been hydraulic fluid on the fitting it is difficult to get a good seal without a through cleaning. Drain all the fluid and clean the gear. Aluminum fittings are generally not recommended on aluminum gear. A steel fitting would be better.
My standard sealant is titeseal. If you store titeseal in high temperatures it must be stirred to remix the components. A thin bladed screwdriver works well for this.
I see nothing wrong with four turns of engagement on the fitting. You may need to try several different fittings to find one that will "clock" properly while avoiding under or over torqueing.
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  #6  
Old 09-15-2021, 03:20 PM
NinerBikes NinerBikes is offline
 
Join Date: Dec 2018
Location: Granada Hills
Posts: 1,193
Default

Quote:
Originally Posted by Bob Y View Post
My gun-drilled gear legs are tempered aluminum, not steel.
And they should be painted, so that they don't let corrosion start in on them.
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  #7  
Old 09-15-2021, 03:50 PM
Bob Y Bob Y is offline
 
Join Date: Jul 2017
Location: Piedmont, SC
Posts: 300
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??? They are painted.
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  #8  
Old 09-15-2021, 10:31 PM
zippymp8 zippymp8 is offline
 
Join Date: May 2018
Location: Olympia, WA
Posts: 11
Default

I had troublesome leaks on my master cylinders that needed clocked, after some research on sealants: I cleaned the fittings/threads with acetone, sprayed the fitting threads with loctite primer N-7649 primer, then used loctite 567. I let the sealant dry for 24 hours then replaced the brake fluid. The waiting period was really what I changed from my previous efforts. Seemed to work for me. I did learn in the process that there are other loctite primers (e.g.7471) for colder temperatures.
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  #9  
Old 09-16-2021, 06:42 AM
JDA_BTR JDA_BTR is offline
 
Join Date: Dec 2013
Location: Colorado Springs, CO
Posts: 1,376
Default

Also, when you tighten the sealant progressively migrates in the threads. When you back off a bit then it isn't sealed.
Any of the approved sealants are fine, but getting it very clean first is smart advice. As is the advice to let it sit a day or so before pressurizing.
You say it bottoms out... how tight is it when you get to the correct clocked position without going past that?
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  #10  
Old 09-16-2021, 12:40 PM
dfvk8n61 dfvk8n61 is offline
 
Join Date: Jan 2008
Location: Cocoa Beach, FL
Posts: 14
Default Try another 90 fitting

Try a couple til you get one that clocks better.
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