RV-4 brake lines

I have aluminum brake lines. There is a coupler in the line about three inches from the caliper fitting. It is a male-male, and the brake line coming from the firewall is flared and connected to it with a B-nut. Then there is a short tube going from the coupler to the caliper.

I need to replace the brake line as it is leaking at the B-nut. The tube is kinked right at the B-nut ferrule and I cannot stop the leak. The brake line is not long enough to remove the bad part and flare.

Question 1: Is this coupler part of the plans, or something the original builder might have done because of he cut the brake line too short? I think there is one on the other gear, but don't remember.

Question 2: Can I run a brake line directly from the firewall to the caliper fitting?

Question 3: Are there options I should consider instead of the soft aluminum tubing?

Thanks in advance...

Brake lines

For me if it brake lines I would use Bonaco,Pegasus lines (these guys are outstanding to work with!)or racing line of your choice. Yes the aluminum and flare work and are effective, no debate. But from a ease of use, I love these hoses on the struts, etc. It has truly been one of the joys of having an experimental aircraft that IMHO has been a great improvement and one less thing I worry about when stomping on rudder pedals or replacing the brake pads as required. No digs against alumimum and flaring as I know they are effective too. Just my 2 cents.

Bonaco lines

My brake lines are Bonaco made lines from caliper to pedal. Not that expensive. Worry free and great service from Bonaco.

CALL BONACO!

Those guys worked with me for what I needed and made me feel like I was their only customer. I ended up adding a plastic sleeve to mine so oil would not get in the braided part.

Question 1: Not per plans. Unless it was a long..long.. time ago.

Question 2: Yes. You will need a loop on the caliper side if you go with aluminum lines.

Question 3: Yes. Per above comment. Call Bonaco. They made me a #3 size line with a #4 fitting. A lot easier to route the line and still have the strength of a #4 fitting. Some pics below. More in my landing gear section of picasa.

Thanks for all the help, much appreciated. I'll give Bonaco a call today and ask them the proper way to make the measurements from the firewall fitting to the caliper and then go from there.

Save your money

Chris-
Check out premade -4 hose from Summit:

http://www.summitracing.com/parts/aer-fcc0406/overview/

The 72" hose was perfect length for my RV-4, running from master cylinders (on the pedals) through the fuse side at the cheek, down to the wheel (similar to Axel's installation, but continuous/without the bulkhead fittings). Much cheaper than custom lines. For custom, I'd recommend TSFlightlines.
Eric

I just went through the same drill last week. I used Pegasus -3 lines, 74" long, and used a grommet where they passed through the sides. Ordered them on line, took about a week, under $100 for both. I also needed to change the fittings on the master cylinder and brakes, 90 degree, NPT to flared AN fittings from Spruce.

AX-O said:

Click to expand...

Can someone tell me if the AN fitting in this photo is an AN822-4D (1/8 thread) or AN822-4-4D (1/4 thread)?

Thanks,

AX-O said:

....

Those guys worked with me for what I needed and made me feel like I was their only customer. I ended up adding a plastic sleeve to mine so oil would not get in the braided part.

.....

Click to expand...

Some manufacturers (not sure about Bonaco) sell a braided hose with a PVC exterior sleeve. Ask about this option before you buy.

ccsmith51 said:

Can someone tell me if the AN fitting in this photo is an AN822-4D (1/8 thread) or AN822-4-4D (1/4 thread)?

Thanks,

Click to expand...

I can't remember. You can look up the caliper and find the size of the hole. thats what I did at the time. I remember having the same question. Sorry!

Thanks, Axel, did some searching and found that it is a -4D, 1/8" fitting.

I thought that was it but I did not want to give you bad info, then when the part showed up and did not fit, you would be upset. Forcing you to travel to CA and punch me on the eye.

AX-O said:

I thought that was it but I did not want to give you bad info, then when the part showed up and did not fit, you would be upset. Forcing you to travel to CA and punch me on the eye.

Click to expand...

Nah, I'm an old fat guy and your pic shows a young in-shape guy, so I ain't gonna think about punching you!!

Tho, I would like a reason to make the trip in my -4 to CA. Been as far as Kalispell, MT, then south to Monument Valley in the RV, but no farther west. Some day I will fly from coast-coast, as there are an awful lot of VAF'ers in that area I'd like to meet.

Chris,

If your -4 has the old style gear fairings (metal) and pants, then the braided lines might require a loop at the lower end vs. a direct turn to the caliper. The Van's drawing showing the brake line at the wheel will give you an example. The folks at Bonaco are top notch.

Cheers,

Vac