Jur's RV7 Aircraft Factory
3497 hours and counting

I bundled the work of the last couple of days in one article. When installing the Bill Lane Plenum, you are required to fabricate some additional custom made angles which do not exist in the standard Vans baffle kit. The primary purpose of these angles is to prevent that the lower front baffle  would rotate forward due to vibration. Especially on the passenger side where the propellor governor oil line passes, this could have disastrous consequences. In my case I have no such line as I have a fixed pitch propellor but nevertheless, I'm going by the plans and be a good boy.

On the passenger side, you have to make a bracket like the one below. The manual states you can also try to make this out of one piece but having them constructed out of 2 pieces rivetted together makes the fitting and tight fit on the engine much easier. Yes it's a couple of grams more weight but that's for the weight fetishists. I made the two parts below out of 0.063" sheet, bend the angle and then started grinding away material on the 3M deburr wheel until I got to the desired shape. Getting the holes for the engine bolt and the upper rivet holes in the right location was a bit tricky.

Here is what it looks like when it's installed on the engine. The front baffle will rest on top of this. As you can clearly see, the bottom angle hooks onto the cylinder base, preventing the whole structure from tilting forward.

 Then I rivetted both parts together with 2 AN426AD4 rivets 

 Reinstalled it in assembly with the front baffle. 

 The inner corner of the front baffle also has to be re-shaped quite a bit. The inward notch is the provision for the prop governor oil line. As said, I don't have that but I'm making it anyway in case someone ever wants to convert it to a constant speed prop.The 2 cleco's in the center right will be the positions where 2 AN525-8R screws attache the front baffle to the lower baffle. That's what the nutplates will be for.

 On the pilot side , this is what the Vans Baffle standard kit looks like. A single bracket attaches to the engine case.

 The Bill Lane plenum installation wants you to keep that bracket and fabricate an additional bracket underneath which will make use of the forward engine attach hole as well. Again to prevent rotation.
The rough shape can be seen below. 

 The little step up will hold an extra aluminum angle that will support the small section of intake ramp that will remain underneath the front baffle.

 Rivetted both together with 3 AN426AD4 rivets

 Some rivetting on the front baffle after closer trimming of the front diffuser fitting line.

 Another modification from the Vans Baffle kit. Vans has a small angle on the intersection of the lower front baffle and the side baffle to connect the corner.
As the Bill Lane plenum has an epoxy diffuser in that location, you cannot use that angle. Instead, you fabricate a larger angler that will sit on the outside of the corner.
I roughly cut the angle in the image below and placed it next to the small angle from Vans for comparison.

A new episode is starting. As the cowling is fully fitted and the Van’s baffles installed, I decided to take on the installation of the plenum.

This has been a long and expensive crusade.

I had first bought the Sam James plenum. In my naive thinking, I thought the Sam James plenum would be the perfect combination with my Sam James Long Cowl.

The first moment it arrived, I already had doubts about the shape and size of that plenum.

As I started fitting it, I soon found out that it would be way too low over my cylinders. I had already read about builders having to use shorter spark plugs, but what really did it for me was the fact that the plenum would even hit my injector lines on top of the engine.

There is no way to move the plenum upwards, as the diffusers are molded onto the plenum. It caused me many restless nights until a fellow builder from the Netherlands told me he had recently purchased another plenum for his RV-7 because he had been experiencing cooling problems with his RV and the SJ plenum.

The plenum he referred to is called the "Bill Lane Plenum", named after William Lane, who invented and built the first version of this plenum.

The big advantages of this plenum are that:

1. It is made to be used in combination with the standard Van’s baffle kit.
2. The diffusers are separated from the plenum roof, which gives you some flexibility during installation.

The diffusers also have a higher up-ramp, which positions the plenum roof higher above the engine, providing much more space over the injector lines and the ignition wires on the spark plugs.

After some research and, to my great surprise, I found out that Bill had sold his moulds to James Aircraft. You can find the link to it here.

I contacted James Aircraft, and they were kind enough to offer me a replacement if I would send back the SJ plenum and pay for the shipping costs of the new one. Getting a box that size back to the USA was rather expensive but in the end it was less expensive than buying the new one. When my replacement plenum arrived, I was very anxious to continue with this part of the build.

Now that I knew what the plenum would look like, I could continue working on the baffles.

First, I made the aluminum spacer, which is a reinforcement piece for the pilot-side rear baffle that holds the oil cooler. Many flying RVs have developed cracks in that corner and have an additional aluminum angle nested in the intersection. I also plan to do that.

 Rounded the angle. All this is off course very theoretical as the real height will be determined by the distance from the top cowling which I will measure when I get to install the roof of the plenum.

Next I started modifying the front baffle on the pilot side. The Bill Lane plenum uses epoxy diffusers which ride on the horizontal line of the front baffle. So you  can cut off the ramps from the Vans Baffles.
Only on the pilot side, you need to keep a small section on the inside. This will be the floor for the pilot side front baffle. I cut it conservatively for now, it will be trimmed down further as I get to fit the front baffle. 

 On the passenger side front baffle, you can cut off the entire ramp. It's not needed. I did keep a couple of mm's which I will final trim once the diffuser is drilled on.
The ramps interfere with the diffuser. You will not be able to position the diffuser with the ramp still in place.

Finally this picture. Learned something new today about my engine. In the center of the rear case sits this port. It is the Tach port or a connection point for a tach meter drive. I had already purchased the UMA tach sensor that mounts on the magneto so I will need to order a cap to cover this port. Andair sells these caps as TC875, "Tachometer cap". Spruce sells it as pn 10-06754. I got mine from PMM wingservice in Belgium.

A big day again in my project. Nothing substantially done but I have hung the propellor on the engine prop hub for the first time.
I kind of wanted an idea how everything would fit together and what is delivered by Catto with the propellor, spinner and saber extention.

I have a 4 inch Saber extention, spool type. This is required for the Sam James cowling installation.
It took a couple of tries to find the way to do this but it's pretty self explanatory once you understand things. The spinner is predrilled and cut and the holes in the spinner plate are also made with nutplates installed. This makes it pretty simple.

Short bolts hang the spool to the prop hub behind the starter flywheel. You bolt these in in a star pattern. I am just doing this temporarily so there is no torqueing involved yet. This will come of a zillion of times. The long bolts holding the propellor and everything forward of the spool extentions are very long. The threads also extend quite far through the extension. This is probably for having enough space if an additional weight plate has to be added up front.

Here is a view with the prop bolted on. This is pretty damned cool seeing this a first time.

Front picture.

Milestone day ! 
This is one of those days that you know mark the timeline of building your airplane. The moment you hang the engine in the engine mount.
After many days of thinking about missing any things on the firewall, I came to the conclusion that this is the right moment to hang the engine and move on to the firewall forward work. There are some more things I need to do on the firewall, but it's not possible to be sure about the exact location to drill large holes in the firewall until I can actually evaluate the position with the engine in place. i'm thinking of the mixture and throttle cable and alternate air cable. Other than those, I'm pretty sure everything on the firewall is in place.

The same thinking goes for the rear of the engine case. Make sure the 45° restrictor fitting for the oil pressure is mounted in the engine case prior to hanging the engine. It's almost impossible to install this once the engine is on the engine mount. Mine was already installed by PMM during engine assembly. While you are at it, also install the other oil cooler fittings in the engine case (in and out). These can also be done later but it's easier now.

First step was to remove the safety straps that held the engine to the wood pallet that was used for transport. I want to keep track of how this was done as this engine is a brand new engine that has not yet been on the test bench. When all is ready, I will need to unhook the engine and bring it to PMM Wingservice to have it running on the test bench for a first time. This has the disadvantage of extra work on removing the engine and all connections again and having to do it again after it has been run. On the other hand, the major advantage is that I do not have to worry about corrosion and idle time of the engine as it has not yet been running. The cylinders are as if they would be in a stock location on a bench waiting for an engine. There has been no movement of the cylinder heads on the cylinder walls and everything has an oil film on it as delivered from Superior Air Parts. Whether building takes me another 3 years or just 1, it won't matter. I'm gladly willing to take that extra work knowing there is no pressure.

The engine was protected well on the front and rear crankcase and supported in the front under the front with some wood block supports. I'll have to keep all this in stock so that I can re use it in the same way when I bring the engine back to PMM.

Using the engine hoist, we pulled it up, removed the pallet and moved it over to the front of the airplane. Alain helped me on this task to keep the engine in position. It's best having some extra hands around when you do this as the engine is heavy and the bolts are not always willing to go in as easy as you think it would. 

The last part of the moving is the most critical as you don't want your magneto's or fuel pump to bump into the engine mount. Having one person moving and another one guiding the engine is no luxury.

Also notice I leveled the airplane in flight mode. This is much easier to position the engine than if it would be sitting on all tyres which would require you to position the engine at an angle. This leveled way makes it much easier.

I found some documentation online from someone who did this before and described the process. I studied this carefully and upfront, had a close look at the barry mounts and dyna bolt set. You can read it following this link https://www.myrv14.com/buildlog/20150917/Engine_Hanging.pdf. Vans Aircraft also has some drawings available which are not part of the standard plan set that you receive with the kit. 

Study the plans carefully, the barry mounts have to be positioned so that the engine rests on the compression side in the bottom and the compression side in the back on the top mounts. The compression barry mounts are the ones that have a step in the rubber. The non compression ones don't have the ribble on it and look like plain rubber. If I remember well, the non compression ones also are a little larger. Also take care that the washers are in the correct locations. The barry mounts come with one big washer in the box. It's good to assemble the order of all this before starting to move the engine and have thing prepared well. I colored the position of the large washer red in the picture above.

There are 2 lengths in the dyna bolt kit. 2 x AN7-43A and 2 x AN7-44A. The longer ones go on the bottom side, the shorter ones go on the top. The difference is not much more than the length of one of the washers.

Start with the 2 top bolts. The first one is very easy... tighten the bolt but don't torque it yet, you'll probably have to loosen them again working on the bottom bolts.
You do need to tighten the first so that the barry mounts compress allowing the other hole to come in line with the engine case. Remember this is a dynafocal mount, the bolts point inwards. If the bolt is not tightened enough on one side, it's impossible to insert the second one. As you tighten the bolts, the barry mounts compress and also position themselves in the engine mount. That's important.

What I found very annoying is that you can't put a socket on the bolt head as the engine mount is in the way.  I used an extension on the wrench but that didn't make it easier.

The engine sometimes needs a bit of persuasion to get it in position :) Although I don't think this did much. Found out later it's more important to tigthen the other side and use the engine hoist to lower or lift the engine a bit in order to get a bolt in.

The large washer goes between the compression mount and the crankcase as a spacer for the bottom mounts. On the top mounts, I have put that washer on the compression mounts under the bolt head as you can see in the image below. The image has both top bolts in place and tightened.

From there on, things went less smooth and it took about an hour or 2 before I got the last bolt in so I did not take any more pictures until it was done.

I'll try to describe the further process I took.

As both top bolts were tightened, I lifted the engine a bit using the engine hoist. This allowed me to slip the barry mounts between the case and the engine mount. Don't forget the large washer between the barry cookie and the engine case. Don't forget the compression side of the barry mounts is against the engine for the bottom mounts. Then I lowered the engine again and after some wiggling I was able to put the 3rd bolt in. I did have to loosen the top bolts a bit though. 

The fourth bolt is the most difficult one. Looking with a mirror through the hole there was no way the bolt would go in. After a lot of moving up and down, I finally discovered my problem : the washer between the barry mount and the engine case was not aligned and the pressure on it is high enough that it makes it hard to move it. After lifting the engine a bit and tapping on it, I could get it more or less into place. 
A second trick I used was to take an old bolt which was smaller in size and grind down into a guide pin. Once I could slide that smaller bolt in, I was able to wiggle it around in order to get that washer and the engine hole into alignment. I put some grease on the final bolt shank and finally was able to put it in with only very light tapping of a rubber hammer.

I was feeling relieved as I bolted the final nut on that fourth bolt.

As final step, I torqued the bolts. These are AN7 which take 450 - 500 inch/lbs. I used the middle value of 480 inch/lbs. The engine will still need to come off as mentioned earlier but the position of the engine is very important when installing the cowling so I torqued it to the final value.

Took some pictures of the plane with the engine in place. This surely is a big milestone and is a "feel good" moment during the build.

Happy camper...

As I had some time left, I took out the fuel throttle body. This comes with a plastic spacer.

The orientation of the throttle body was a bit of a mystery at first but soon figured out what side was the throttle lever and which side the mixture. 
In the image below I installed it on the forward horizontal induction air intake at the cold sump of the engine. In the image below, the throttle lever is the gold colored arm.

Finally I covered the intake with some paper and masking tape in order not to get foreign objects entering the engine.

End of a productive day was off course celebrated with Alain with a good strong Belgian HQ beer.