How much brake fluid needed?

[Jekyll]

I'm filling my brake system and would like to know how much I need. I have 1 quart. I seem to have used 1/3 of it and only have fluid up to 1 pedal line. I quickly found a bad aeroquip line. Fluid is squirting out around the gold swivel end and the fitting. Need to replace that.

Riveting and wiring is easier and more predictable than the final push! Once I get this done I can rivet on the last skin and glass in the wind screen - then to paint and final assembly!

7A with dual brakes and a parking brake.

Jekyll

 

[jdiehl]

Jekyll,

I filled my brake system (7A) within the past few months and would guesstimate less than a quart. The problem I dealt with was bubbles that appeared overnight in the tubing. They were apparently hiding in the master cylinders. It took several re-fills 'till I got them all pushed out of the system. All told, I've used well in excess of 1 quart. Recycling the excess fluid that comes out of the reservoir may keep you within the 1 quart.

Jim
7A -allllmost done

 

[704CH]

Suppose it might depend on if you have right side brakes or not ? Also brake line to reservoir routing.

 

[alpinelakespilot2000]

< 24 oz.

Just got done with mine. Took less than 24 oz. for a dual brakes with parking brake installation. I started off with 1 quart in an oiler. After pumping a fair amount into the system and back into the now empty quart bottle through the reservoir overflow (in the 3-4 attempts it took to get all air bubbles out), the quart bottle again showed 8 oz. Added to that, however, I still have a little bit in the oiler and I spilled a fair amount on the garage floor when my hose accidentally came off the bleeder valve. (Make sure you don't have any leaks inside the plane because the stuff stinks!) If you don't want to reuse anything you pump back into the fluid bottle from the reservoir, then planning on a quart is a good bet.

 

[Jekyll]

Thanks Steve.

Yeah, got a leak from a bad hose. Need to replace the hose and clean the plane.

I'll be ready to rivet on the top skin once I get the brakes bled. Are you still tracking neck-to-neck?

Jekyll

 

[Jekyll]

OK, I can now update my own question. Fixed my leak and bled my brakes tonight. I used about 2/3 of the quart including 1/4 cup of spillage. Bleeding took about 45 minutes once I got things set up. Did it by myself and it went fine. I used an oil pump can from Tractor Supply Co.; they also had clear fuel line for input and output flows. Got a fitting for the reservoir from an auto parts store. I did need to buy a new reservoir cap from Vans because mine stripped as it came out. Several others have reported this isue so, I recommend others buy a spare cap when they place an order from Vans. It will save shipping costs and delay when you you get ready to bleed your brakes. Caps cost $2 so it is cheap insurance.

I should get to the paint booth in March. Top skin can go on next week and that just leaves canopy glassing and wheel pants. I should be ready to fly right about the time the salmon run starts. Will I fly or fish, fish or fly - choices, choices. Hopefully, I can get it done in time to fly to the lake this year. I'll need to put a junker airport car at the lake so I can fly up and back.