Firewall prep, engine mount and gear reinstallation

The remainder of canopy work, mostly laying up the fiberglass front fairing, is on hold until warmer weather. So for the last two weeks I’ve been working on laying out and installing everything that needs to be on the firewall before the engine mount is permanently reattached.

Firewall hole layout

Throttle, mixture and prop cable penetrations laid out on firewall.

Cheap hole punches at work

Cabin heat control box mounting holes cut, using my inexpensive Lowe’s knockout punch to cut the throttle cable penetration.

Deconflicting the throttle and fuel bulkhead passthrough

Not a super clean hole, but better than I could have done otherwise.

Modified fuel reinforcement

Fitting the fuel line penetration doubler.

Firewall progress shot

The oil filter cutout and battery box are in temporarily installed so I can begin laying out battery and starter contractor locations.

Fitting starter/battery contractor doubler

Fitting the starter/battery contactor doubler.

Battery and starter conductors temp fitted

Battery and starter temp fitted, laying out location of ANL fuse holder and current-measuring shunt. The relative locations of the battery (top, silver) and starter (black, bottom) contactors was as close as I could get to Van’s plans locations while still accommodating the different style of starter contactor sold by B&C.

Doubler laid out for ANL holder and shunt

Doubler outline laid out, ready for fabrication.

Delayed by physical fitness

Mid-April – a running misstep led to a fractured ankle. No airplane work for a couple of weeks…this sucks.

Riveting things to the firewall

Back to work in early May despite the booted ankle.  With Ellen’s help, we got the contactor/fuse/shunt doublers and nutplates riveted to the firewall.

Electrical component doublers

The result of an evening’s work – battery and starter contractor doublers and nutplates riveted to the firewall.

Everything riveted to the firewall

Everything (almost) is now riveted to the firewall, ready to install electrical components, battery box and control cable passthroughs.

A mostly populated firewall

I was able to sneak away for a few hours and get most everything installed on the firewall. A few minutes of work for a nice little bit of visual progress.

2016-05-14 14.46.50

Fast forward a few days to finishing firewall prep and permanently reinstalling the engine mount. Ellen joined me at the hangar to help with fitting, bolting, torquing, hoisting and gear reinstallation. No more ankle boot, so moving around the airplane was a lot easier.

Fuse on the hoist for landing gear install

With the engine mount firmly and permanently attached, we hauled out the engine hoist and tow strap to get the fuselage high enough for the landing gear to be reinstalled.

Back on the gear for good

…and the fuselage is back on the gear for good. It’s engine hangin’ time!

Fun with brake installation

Back before we moved the project to KASH, I temporarily installed the engine mount and landing gear so we could move the fuselage more easily. Because it’s almost time to permanently reinstall both items, the brakes need to be installed before the airplane is on the landing gear for good.

This is probably the most poorly documented part of the project so far in Van’s instructions, in part because they reference Cleveland wheels and brakes – and Van’s delivered MATCO wheels and brakes with my kit. I don’t know why and I don’t think I asked for them, but whatever.

One of the big differences between Cleveland and MATCO wheels is MATCO’s use of sealed wheel bearings rather than Cleveland’s unsealed versions. Bearings with an integrated dust seal last longer, but they’re harder to pack with grease – I couldn’t use my spiffy Lisle bearing packer device which pushes grease through the bearings.  Instead, I had to put on rubber gloves and pack them by hand by shoving grease into every available nook and cranny.

Repacking brake

Yes, it’s a messy job.

One other thing to note about MATCO wheels is that the bearing races are milled into the wheels themselves, and the bearings don’t rotate around the axle. Therefore, it’s important to torque the wheel nuts sufficiently to provide enough friction to keep the bearings from rotating.

Wheel pant bracket

The drawings are also unclear about how the brake caliper and wheel pant support brackets are arranged on the axle. So for those of you who are scratching your heads over this as I did, here are a couple of pictures that show how the assembly goes together. In both pictures the large portion of the wheel pant bracket pointing up, is oriented forward with respect to the airplane.

Reinstalling wheel bearings

Another thing that wasn’t clear was how to get the brake caliper apart to fit it over the brake disc. It’s actually easy, there are two bolts on the back of the caliper that are removed, then it’s an easy matter to install the wheel, torque the wheel nut, then slip the caliper back in place and reinstall/torque the caliper bolts.

Brake caliper removed

Getting real

Over the last couple of weeks the heart of the Mighty RV arrived at the ThermosWorks. If you recall from past posts, I engaged Tim Hess at Unlimited Aero Engines to build, flow-match, balance and test a Superior XP-360 engine.

The heart of the Mighty RV

In mid-February, Tim delivered this work of art to the hangar. It’s been test-run on a dyne stand and produces 184.9 horsepower. The rocker box covers have been hydro-dipped in a carbon fiber weave pattern – Tim’s idea, and they look great…

Hydro-dipped RBCs

In fact, they look so nice that I’ll replace them with stock covers until the cowl is fitted!

A very red engine

The choice of color was Ellen’s, and as usual, she was spot on.  The engine is gorgeous, and my only concern is keeping it looking this way once it’s in the airplane.

The other chambers of the Mighty RV’s heart were drop-shipped from Piqua, Ohio by the good folks at Hartzell Propeller…

A big fan

Not much to see in the box, and the prop will stay there for awhile until it’s time to put it on the engine.

A closeup of the fan

It’s been a long haul to get to this point, and with the delivery of the engine and prop, everything has suddenly become a lot more real…it’s easier to envision this assemblage of aluminum, steel, plastic, blood, sweat and tears as an airplane.

An engine is born

I stopped by Tim Hess’s engine shop today to see major parts of the engine coming together as Tim joined the case halves.

Engine case halves

Just getting to this point involves a lot of work – Tim has already balanced the major rotating components, checked tolerances on the bearings (and in some cases replaced ones he wasn’t happy with) and flow-matched the cylinders.

Case halves bolted together

One of the reasons why I didn’t want to do this myself – the first time, at least – was that there are a lot of things that appear to be easy but can easily be done incorrectly, like applying the silk thread that’s used to seal the case halves, or laying down lubricants and sealants on the crank and cam.

Case halves on the stand

I’m very happy with how everything is coming together on this part of the project. Later this Fall or Winter, it’ll be time to hang this thing on the fuselage.

Getting a look at our engine parts

Today I visited Tim Hess to look at the Superior XP-360 parts that Tim will be assembling into the Mighty RV’s engine.

Tim and the engine parts cart

I was really impressed with Superior’s parts kit…everything organized very neatly.

Dave's crankcase

It’s almost a shame to paint this beautiful gold-alodined crankcase, but Ellen and I have agreed that the crankcase will be painted red.

Dave's cold air sump

Here’s the Superior cold-air sump. I was impressed with the casting and milling, and Tim pointed out several areas where the Superior sump is better than the stock Lycoming part which embeds the intake tubes in hot sump oil.

One of Dave's cylindersAnd here’s one of the cylinders.  These aren’t going to be painted…they’re just too nice to cover up. Superior makes very nice parts…

And the engine is…

It’s looking likely that I’ll be ready for an engine sometime this summer and over the last year I’ve been working through the various engine options for our RV. Many years ago I decided that the engine would be some variant of the 180 horsepower Lycoming IO-360-M1B with a horizontal sump and set up for a constant-speed propeller.  I’ve already purchased a finishing kit from Van’s that includes a cowl for this configuration.

When I first started building the RV, I planned to buy a certified Lycoming engine from Van’s because of the excellent prices they offer to RV builders. But since Van’s now only carries experimental versions of Lycoming engines, and there’s competition in the experimental market to keep prices down, we decided to expand our search and look at ECI Titan and Superior XP-360 experimental engines from other vendors.

An advantage to buying an experimental engine from one of these vendors is that they do some value-added work like flow-matching cylinders and balancing rotating components. I really want a smooth-running engine, and these tweaks apparently help. Had we been buying an engine a few years ago, we might well have worked with Mattituck Services on Long Island. They had an excellent reputation for customer service and sold experimental engines to many local RV builders. But they no longer exist as a custom engine builder, so that option was out. I had also been investigating engines from Aero Sport Power in Kamloops, British Columbia. Many west-coast RV builders, including my good friend Jim Piavis, bought engines from Aero Sport and have been very happy with them because of their great after-the-sale support. I defintely want that kind of support from my engine provider.

One of the factors in my selection process was the choice of fuel injection systems. I’d pretty much settled on a Precision Silverhawk EX system because it’s the experimental version of, and identical to, the proven Bendix RSA system that I’ve flown on Piper Arrows. Until recently, experimental Lycoming engines sold through Van’s came with the Precision system but as of 2014 Lycoming switched to Avstar fuel injection systems – essentially a knockoff of the Precision system. I’ve had several interactions with Alan Jesmer and the folks at Precision, and decided that I wanted my engine to have their FI system. Since Van’s wasn’t willing to customize the Lycoming engines they sell, this wound up being a vote against buying an engine from them.

I had almost decided to buy my engine from Aero Sport this spring, but decided to ask my A&P/IA friends around Boston about local engine providers. They all pointed me to Tim Hess at Unlimited Aero Engines at the Fitchburg, MA airport (KFIT). Tim was formerly the Crew Chief on Mike Goulian‘s Red Bull air race team, he’s built highly customized, high performance engines for Mike and Kirby Chambliss. In addition to continued support to the Red Bull Air Race organization, Tim runs his engine shop at FIT and has done overhauls and repairs for many of my A&P friends. In short, he’s a world-class aircraft engine expert.

At the suggestion of my good friend Captain John, I visited Tim’s shop a couple of weeks ago and asked him for a quote on an experimental IO-360-M1B engine. He came back with a very competitive price on an custom-built Superior XP-360 with a cold-air sump and horizontal induction, roller lifters, Precision fuel injection, one PMag and one Slick mag, with flow matching, balancing, test stand run and documentation. Tim seemed really interested in building an engine for my project.

I really like the idea of working with a local shop on my engine, and it’s not every day you get a chance to work with someone like Tim who just happens to be in my aviation back yard.  Plus, there’s the added benefit of having no sales tax in Massachusetts on aircraft parts. So, two days ago I wrote Tim a check for one of these…

Superior XP-360

…and sometime later this year our RV will finally have an engine.  I’m looking forward to working with Tim, and I’ll be updating the website as we continue toward delivery of the engine.

A battery diversion

I’ve been getting frustrated with the canopy and have also been waiting for some blind rivets and other hardware I need for finishing up the fuse. So, I decided to build the battery box as a small diversion. A quick day’s work except for painting…

Battery boxIn all likelihood I’ll mount it according to Vans’ firewall forward mounting plans but until I’m ready to do firewall stuff, the battery box will be waiting on the shelf.

Fire, ice and grease

Getting the gear legs attached to the engine mount turned out to be a pain in the posterior. For some of my friends, the legs went easily into the gear sockets but I wasn’t so lucky.

Heat Gunner

I wound up greasing the crap out of the gear legs to make them go in easier, but that only got them in part of the way. I had to get a little creative at that point – I grabbed my trusty heat gun and warmed up the gear sockets just a little to expand them.

Ice bags

I also put some bags of ice on the gear legs themselves to shrink the metal ever so slightly.

Socketed gearMy very good friend Burt also came over to help.  He kept a firm hand on the fuselage to keep it from moving while I pushed, pulled and twisted on the gear. Thanks Burt!

In the end, we got the gear legs in…but it was a lot of work.