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RV4 Rudder Pedal Drawing

BootsRV4

I'm New Here
Hi team,

I have had to detach my brake master cylinders to achieve a proper brake bleed. In looking at the rudder pedal hardware I am suspicious about the hardware that was used by the builder. I have ordered the thumb drive package from Van's but that will take some to arrive. Since I have the right rudder pedal apart it is an opportunity to reinstall it with the correct hardware. Is it possible please for anyone here to post the Van's drawing for the rudder pedals?

Many thanks.

Boots
 
This may help.
 

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Thanks Flyhud,

My suspicions confirmed. Interesting that the drawing shows the MC in the upright position whereas inour aircraft they are inverted. In searching this and other sites it seems that many RV4's have inverted master cylinders.

Cheers
 
Bleeding..

You will find them installed both ways, and it really doesn't matter, though I like the "per plans" installation. Over the years, many have been challenged with bleeding brakes on the RV's. They can be a nightmare if trying to use the pump and bleed 2 person process, and you will likely never get them bled out. It was recommended to pull the cylinders and flip them to release the bubbles, but as you found out, that is a PITA. I , as well as many others, prefer to "bleed up" from the caliper nipple using a pressure system and and push fluid from the bottom to the top, which will remove every bit of air in short order. Some use a store-bought system, others are DIY. Mine is a simple pump oil can filled with 5606, a piece of clear hose that is clamped on the can and put over the bleed nipple. I have a fitting with a drain hose that goes on the reservoir cap boss and empties into a container. Simply pressurize the line with the pump can and keep pumping until the reservoir is overflowing into the can. repeat for other side. One man job, 30 min and your done.
 
Pumping what?

Ive done the pump fluid up the bottom on alot of airplanes but mever couldget it to work on my upside down mater cylinders...when you say pressurize and then keep pumping...you mean pumping your oil can or pumping thebrakes?
The only way i could ever get the air outwas to take the cylinders off and right them..

Just curious
Cm
 
Here's something to check -- on my old RV-4, pushing, say full right rudder would apply left brake (!). Certainly made for an exciting takeoff one day, but at least I went between the runway lights.

This same phenomenon was found on at least one other RV, don't recall the details.
 
Pump the oil can!

Chris, I was referring to continuous pumping of the oil can, or if you have a pressure bleeder that uses air. The flow of hydraulic fluid has to be continuous and "push" the air up and out all the way to the reservoir. There is never a need to pump the pedals when pressure bleeding , as the fluid will travel through the brake master cylinder when its not compressed.
 
Brake cylinders

In the process of redoing the brake cylinders on a project I picked up. They had the cylinders installed upside down, and in the process plumbed the tubing so the high-pressure outlet was going to the reservoir.

Will be working on it this weekend, but it appeared the bolt called out for at the bottom of the cylinder, the AN23-15, Is not long enough to get the nut on far enough for a cotter pin. Any thoughts? going to order dash 16-17 And see if one of those will work without interference per
 
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Be careful with the bottom bolt!

The bottom bolt for the master cylinder can be a loss of control problem if its too long and has a cotter pin in it, due to the angle of the center tunnel and the swing of the pedal. It can hang up on the tunnel and you can lose control of the rudder. I have seen several that had wear marks where the cotter pin tried to snag the tunnel but they were lucky. I have a low profile all metal locknut on mine and no cotterpin. Check your clearances closely. I've attached an old picture of a picture, but you cant really see it well.
 

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Clearance

Thanks. Yes I can see that clearance can be an issue to watch out for, I will consider a low profile soft locking up, no cotter pin.
 
"per plans"

Note that the builder's manual allows to mount them so they are easy to bleed.

But it can be a tight fit.

I added a steel strip between the two alum angles that forms the "well" between your feet, to pull them together a bit and make sure that they could not be pressed out (in tension) to interfere with the brake cylinders.

Finn
 
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