ELT & Strobe Power Supply Installation with Van's Mounts

Van's Aircraft has come up with a nice pair of ELT/Strobe power supply mounts for both the right and left sides of the RV 10. These are not part of the kit, but are available separately. At the time I installed these they did not make one for the right side. But with a little work I was able to get it to fit. As you can see they are mounted into the J channels with "pop rivets." They come pre-punched for the Whelen strobe power supply with the rivets and nutplates included. To mount the ELT I had to drill new mounting holes in the left mounting plate that matched the Emergency Beacon Corps unit. All in all these mounts make for a nice clean installation.

Modifcation of the Front Fresh Air Vents

Being value minded, when it came to the front air vents for the RV 10, I wanted a nice set of vents without paying an arm and a leg. OK well maybe just an arm. The simple solution was the fresh air vent AV125B available from SteinAir. Aircraft Spruce carries as well. Most people who use these are also using a custom instrument panel, however I had opted for the stock panel from Van's Aircraft. So how does one mount the vents without an extended panel? The idea for the fix came from the Matronics group. First cut off the bell end of the cabin side of the vent and then use a adapter made from a rubber pipe coupler from Home Depot. You only need one coupler and then cut it in half. Using fuel tank sealant I glued the coupler to the plastic vent and a hose clamp secures the vent in the coupler. One other nice touch is to take some stainless wire screen and glue it into the middle of the plastic neck with fuel sealant to keep the bugs out.

Lycoming Oil Sump Clearance on the RV 10 Engine Mount

A concern that comes up with different variations of the Lycoming IO 540 is will the oil sump clear the lower cross tube on the Van's Aircraft motor mount? The tube in question is pictured to the right and is the one that runs between where the two lower vibration mounts bolt on. This has become a big enough issue that Van's wrote a service letter on it: RV-10 Engine mount/Engine interference.

As you may recall the Lycoming IO 540 C4B5 I'm working with is from a Piper Aztec. The good news is there is no interference issues with this engine. The clearance was right at 3/8". I'm not sure if all C4B5 use the same oil sump, but the right engine on a 1974 Aztec works just fine:)

If there is interference there are two fixes I have heard about primarily through the Matronics RV 10 e group and these are: 1. get a different sump or 2. cut out the tube and weld in a new one that is bent to clear the oil sump. I'm just glad it was a non issue for me! If you are not familiar with the Matronics RV-10 Aircraft group check it out. It is a great resource: Matronics sign up

Lycoming IO 540 Ring Gear Assembly (flywheel)

Another item that is an optional change is the Ring Gear Assembly. Why would anyone want to change it? Well, the one that came with my engine was setup for a Hot Prop or deicing propeller. As you can see in the first picture the hot prop gear assembly has greater mass than the standard ring gear assembly shown in the second picture. In short it's a way to save some weight in the nose of the RV-10. The hot prop assembly weighs 8.86 pounds. Were as the standard ring gear assembly weighs 6.9 pounds.

A couple of things to keep in mind about this change out is to use the same tooth count on the starter ring gear that matches the starter being used. They come in 122 and 149 count. Also, you will probably want to stay with the same alternate gear pulley size. The standard Lycoming size is 9 3/4". This is the size recommend for use with Plane Power alternators.

While changes such as this are legal on homebuilt aircraft, it can change a certified engine to an experimental engine depending on the part used. Also, it's important to document changes such as this in you engine log book for later reference.

Manifold pressure tap on the Lycoming IO 540 C4B5

If you are planning on using an IO 540 out of a Piper Aztec keep in mind the manifold pressure tap is on the number 6 cylinder (this the left rear cylinder from the pilots view) whereas Van's has used a tap off of the number 5 cylinder (right rear.) I mention this as a heads up to make sure the old pressure tap off the number 6 cylinder gets properly plugged, otherwise that cylinder would run really lean if at all!



In the first picture you can see the number 6 cylinder with a new plug installed with fuel lube and torqued to the correct setting.










The second picture shows the newly installed manifold tap as used on the RV 10 aircraft.

Lycoming C4B5 Power Rating for the RV10

As we discussed earlier the IO540 C4B5 has a different power rating than the IO-540 D4A5 recommenced by Van's Aircraft. These are 250 HP at 2575 rpm for the C4B5 and 260 HP at 2700 rpm for the D4A5. Everything I have read points to the fact that they are the same basic engine and capable of running at either rpm/power rating. It's just Piper derated the C4B5 by running it at a lower rpm for the Aztec. If you would like to explore more about the different Lycoming 540 series aircraft engine try this link Lycoming 540 reference.

Lycoming engine mounting ears

To ready the Lycoming IO-540 C4B5 for the RV 10 the engine mounting ears must be changed. The C4B5 comes with the large diameter mounts. Where the Van's engine mount requires the small diameter ears. The accompanying picture is of a used example of the correct part. The required mounting ears are Lycoming's part # 70456. A none PMA'D experimental part is available from A.E.R.O. Here is a link to their website www.aeroinstock.com Also, they are available second hand or from Lycoming.

Changing the Propeller Governor

As we mentioned before there are some things that need to be changed to get the Lycoming IO-540 C4B5 to fit our use on the RV 10. One of these is the propeller governor. The original unit for the Piper Aztec won't work for several reasons. First it's too bulky to fit under the RV cowl, but more importantly being it is used on a twin engine aircraft it feathers the opposite direction from what we need.

In the picture you can see the difference between the original on the right and the MT governor on the left, which is available through Van's Aircraft.


Of course the fun doesn't stop here! As you can see in the photo the mounting flange on the MT unit is thicker. So the mounting studs will need to be replaced with the longer ones. These are available from Lycoming, however I purchased mine through ECI (Engine Components, Inc.) at about half the cost. Yes, they will deal with us builders. The ECI part number for the new studs is AEL31C16. If ECI sounds familiar it's because they make Titan engine cylinders and other aircraft engine parts. Their website is www.eci.aero.

Make sure you get you Lycoming engine manual out and install the new bolt studs according to the manual. If this is new to you ask your EAA technical conselor or and A&P. Engine cases are too expensive to mess-up!

Fitting a Lycoming IO540 C4B5

The prototype RV-10 aircraft used a Lycoming IO540 D4A5. The second factory plane used a Continental IO360. To save a few shekels we used a rebuilt variation on the aircraft engine the Lycoming IO540 C4B5 out of a Piper Aztec airplane. Of course there are some difference between the two engines such as:
Power rating

Engine mounting ears

Hot Prop Flywheel

Prop Governor

Prop Governor mounting studs

Manifold pressure source

Modifying the RV-10 lower cowl mounts

Experimental aircraft have the advantage of allowing the homebuilder to make modifications when needed. One that has come up with other RV-10 builders is the two lower cowl mounts will crack. The original Van's kit called for using aluminum hinge material. It's referred to on pages 41-7, 41-8, 47-6. Others have replaced this with 0.063 aluminum sheet and nut-plates with good results. We followed suit.

The dimensions of the 0.063 aluminum is 1.5" by 6 ". The smaller aluminum spacer is made per the plans. The hardware pictured consists of 8 each K 1000-8 nut-plates, nylon washer 5610-18-31 and AN526C832R8 stainless screws. These are all available from Van's Aircraft.

6,000 RV aircraft now flying!

Well it happen today the 6,000 Van's airplane kit is flying. As fate would have it, number 6,000 is an RV 10 registration number N510RV. That makes 166 RV-10s flying according to Van's website. Louis Palmenter of Rhome Texas is the latest happy builder.

Starting a RV-10 homebuilt airplane

OK this is more history than current. On December 27th 2004 we unpacked our Vans RV-10 tail kit and started a journey four plus years in the making. This was sometime ago but we will work at catching up this blog for the. If you are just joining us check back, as our goal is to provide weekly updates on building the RV 10 aircraft. Here are some pictures as we first got started on the tail feathers.

Past Airplane Projects

It's said aviation is in the blood, well maybe. This page is dedicated to some of our past aircraft. And yes we are still under construction;) If you want to see a larger image of the airplanes just click on a picture.





Here is the before picture of our 1965 Cessna 150E that I refurbished under the watchful eye of an IA.













Paint was restored back to the factory scheme and colors. Last time I heard the plane was in Alaska with its new owner. New seats and carpet are by Airtex. Seat belts and shoulder harnesses are from Wagaero.





A young Ethan give our Mooney a thumbs up when we bought it.