Brake line main gear replacement
 

Hi All

I have to replace the brake line attached to the main gear leg(pitting has lead to a pin- hole), thought I would ask the group if there is a specific way to remove the tubing once disconnected from the swivel, back of the leg and calliper.

Maintenance manual only refers to this brake line as part of the main gear stating to leave it attached to the main gear during leg (strut) removal.

Appreciate any guidance before I tackle the task.

Dave

Dave

Jack the aircraft, partially retract the gear, lift the gear and place tire on top of a two step ladder is the easiest way. This makes the line accessible, disconnect the B fitting at the top of the gear and at the caliper flexible hose and then slide the clips off the gear leg with the line. If you are going to make a line pay particular attention to the bends at the top. When the gear is down the line can get pinched very easily if the bends are not correct.

With the gear in this position it is very easy to also change the flexible brake line in the wheel well, as well as removing the flex fitting and replacing the seal in it. Directions for disassembling the flex fitting is on other threads on the forum.

Dan
N67S

you can remove rear seats, lift carpet and floor plates also with excellent access to brake components in the landing gear well (and don't have to be on a jack).

If you have corrosion eating through the line, you probably have corrosion in other parts of the system as well as old out of date components. Plan on replacing o-rings in master cylinder and calipers if there's that much corrosion and not recently done. Check all your flexible lines. I had pitting corrosion in my caliper bores that allowed hydraulic brake fluid to ooze out around the piston and made things gummy around the brakes along with brake softness, but not enough to cause a telltale drip. Tried sanding it out but the pits were too deep. Ended up replacing them and be aware there is back log/lack of inventory. The Cleveland cross reference manual on line is wrong for our later models. You will have to do some research to get parts.

Knots-2-u sells affordable master cylinder rebuild kit. If doing the Lock-o-seal be sure about the gap.

The swivel was too much of an "unobtainium" in my mind to try and rebuild with the risk of damaging an irreplaceable component. So I sent it out to the only place I could find that would work on it and test it afterwards.

Parking brake valve rebuildable via o-rings and can be a source of some issues.

If you have the jacks easier in my opinion. Kind of a PIA to remove all that stuff, plus you don’t have to use a 90 dollar tube of the red PRC compound to seal the plates.

Swivel fitting is actually pretty easy to do. Hardest part on reassembly is to use 2 pieces of aluminum on your vice to squeeze the two parts together to install the retaining circlip.

Dan

Just goes to show the differences. I assumed a non pressurized G model here (which wouldn't require resealing). Plus my rear seats are adjustable and just slide out. If pressurized, would not want to lift those floor panels.

Interesting on the swivel. Mine didn't have a circlip (which would be manageable) but a type of spring diaphragm that was certain to get bent out of shape on disassembly...

My bad, looks like his is a non pressurized model.

Dan