Jan 03, 2024     Heat sink       Category: Engine

My fiend and fellow Hatz confidant AC Hutson came for a visit and pointed out that I might have too small of a heat sink for my ignition modules. So I ordered a couple heat sinks like what are used in electronics and fashioned new heat sinks. Should do the trick.

  Jan 13, 2023     Backup battery       Category: Engine

I've been concerned about having back up for the engine electronic ignition. I've been accustomed to magneto simplicity and no reliance on an energy source. I decided to install a small EarthX 12v battery that I can switch to in the event of battery/alternator failure. I installed diodes and a switch that allows the battery to be charged by the alternator when not in use, but will isolate the battery to one ignition side from the rest of the electrical system when called on. The battery is mounted on a try just forward of the instrument panel. I plan to instal a connector to all me to periodically check the voltage, as well as connect a trickle charger specific for lithium batteries for winter storage.

  Jan 07, 2023     Fuel pump shroud       Category: Engine

Since the fuel pump for the Rotec is mounted on the top of the engine, I have been concerned about hear induced vapor lock. I made a small shroud with cold air blast tubes to cool the pump.

  Dec 21, 2022     Firewall forward       Category: Engine

Completed installation of oil/fuel lines as well as firewall forward wiring. I used lacing in most applications with securing hoses and wiring. I had Aircraft Specialties manufacture all pressure oil lines as well as fuel lines. I had them use the interval fire sleeve type fuel lines and highly recommend them.

  Feb 24, 2022     Oil fill neck extension       Category: Engine

I wanted access to the oil filler neck to be as simple as possible, it being located on the top of the fuselage, so I opted to have it extend through the boot cowl. Also adds to the vintage look. I made a hole locator template and then transferred that to the cowl. When I fill the tank, SOP will be to have a rag placed around the neck to prevent spills causing a mess.

  Feb 22, 2022     Oil tank baffle       Category: Engine

One thing that has bothered me since I had my oil tank welded up is not providing for a way to decrease the chance of oil foaming. It's a problem that is emphasized to prevent when running a radial engine with a remote oil tank. As I had it, oil would return to the tank at the top of the tank, pouring straight down unimpeded. Like pouring a beer straight into a mug, and getting a whopper of a head. Add to that, the level of the oil would be reduced while the engine is running, making the length of drop even higher, causing even more foaming. So a simple solution was searched for before a wholesale revamp of the tank was done. I came up with inserting an angled baffle across the back of the tank positioned under the return fittings that directs the oil toward the back wall of the tank. Again using the pouring a beer along the side of a mug to prevent creating a big head analogy. So I made two slits in the tank and inserted a piece of .050 aluminum. Again, master welder Craig welded it up for me. I'm a bit more comfortable with the result, warranted or not.

  Jun 09, 2021     Speed ring primed       Category: Engine

Primed the speed ring with high fill primer. This required a few coats with glazing putty and sanding between. A long process, but I hate pinholes. Making the speed ring from a mold would have eliminated 90% of the pin holes, but I was burned out making the cowl mold to do another, soba one-off ring was opted for.

  Jun 01, 2021     Speed ring baffles       Category: Engine

Completed the engine baffle extensions including the flexible baffle, less that at the top of the engine where the lift point is. I'll complete that once the engine is mounted permanently. Pulled the project out of the shop with the cowl and speed ring mounted. Sometimes you have to savor the accomplishments along the journey's path.

  May 19, 2021     Rocker valve covers       Category: Engine

I had heard that the current Rotec valve covers have a tendency to leak and that Hans and Sam Gauchi had designed and produced a set that are milled and a bit stiffer, so I went ahead and installed them so I could get a good fit go them with the baffle extensions. I checked to see what clearance I had with the speed ring installed.

  May 10, 2021     Engine baffles       Category: Engine

Since I have decided to include a speed ring, I started making baffle extensions

  May 02, 2021     Mounting speed ring       Category: Engine

Made delrin mounts to work with custom rocker cover mounts. Two aluminum angle sets were mounted with bolts between them to squeeze the ring to the rocker cover mounts. Aluminum sleeve was made to cover the joint where the ring comes together.

  Apr 02, 2021     Speed ring fiberglass layup       Category: Engine

Waxed speed ring plug. Laid up 5 layers of 9 oz cloth and one layer of 3 oz cloth

  Mar 15, 2021     Speed ring plug continued 2       Category: Engine

Applied a coat of epoxy resin to harden the plaster skim coat

  Mar 11, 2021     Speed ring plug continued       Category: Engine

Applied foam and joint compound plaster to plug and sanded to shape

  Mar 10, 2021     Speed ring plug       Category: Engine

Decided to build a speed ring. Began making a plug from masonite and plywood.

  Feb 25, 2021     Cowl and engine trial fit       Category: Engine

Remounted engine and installed cowling top and bottom halves.

  Feb 18, 2021     Scat tub mounts       Category: Engine

Installed scat tho mounts in two baffles for cold air induction tubes.

  Feb 16, 2021     Intercylider baffles       Category: Engine

Constructed and installed inter cylinder baffles. Attached at the top with brackets secured with intake and exhaust studs. Secured at the bottom with music wire clamps. Shaped at the back of the cylinders to direct air to the back side of each cylinder.

  Apr 22, 2020     Throttle cables       Category: Engine

Preliminary installation of throttle, mixture, carbheat and primer cables. Mounted primer knob on left sub panel

  Apr 22, 2020     TBI throttle linkage       Category: Engine

Constructed linkage for TBI for better leverage and direction of travel

  Apr 22, 2020     TBI throttle linkage Category: Engine

Constructed linkage for TBI for better leverage and direction of travel

  Mar 22, 2020     Airbox mounting       Category: Engine

Mounted the airbox. I made a couple modifications to the airbox prior to installation. First, I made an aluminum support ring to sandwich the fiberglass box between the TBI and the ring. Didn't like relying on the fiberglass to be strong enough. Then I made an alternate air/carbheat door. Happily the box just fits between the TBI and the firewall. I installed a small tab at the outboard edge of the airbox for more support. I plan to isolate that with some neoprene rubber for vibration isolation. Otherwise it could fracture from the engine moving around.

  Mar 21, 2020     Remounted engine       Category: Engine

Remounted the engine to provide reference for airbox mounting. Mounted master solenoid

  Mar 19, 2020     batter box mount       Category: Engine

As the battery, in this case an Odyssey PC 680, is quite heavy, I also wanted it to have good support as well. I located the battery box and welded 4130 sheet to the fuselage tubular structure to support the battery

  Mar 16, 2020     Oil tank mount       Category: Engine

Mounted the oil tank. I am using a method recommended to me by an experienced builder where no tabs are welded to the tank that could fatigue and fracture. The tank is supported on the motor mount by a sheet of plywood. This sheet is attached to the motor mount with two clips. The tank is then strapped down onto this plywood mount with a stainless steel strap that is attached to the motor mount via two bushings with two bolts that are welded to steel plates that are in turn riveted to the stainless steel straps. Rubber bumpers stand the tank off from the firewall, and two angles with rubber bumpers keep the tank from sliding side to side that are located along side the lower part of the tank that extends through the plywood mount. It is quite secure.

  Mar 09, 2020     Electric scavenge pump mount       Category: Engine

As I am going with an engine that has a dry sump, a separate oil tank is used. Oil needs to get back to the main tank from a small sump on the engine via an engine driven scavenge pump. An auxiliary pump is recommended which I have purchased from Radial Conversions. The pump itself is quite hefty, so relying on the stainless steel firewall to support it is not a good idea. I fabricated a 4130 steel plate and welded it to the fuselage tubular structure for adequate support. Not a good demonstration of my welding skills. I was a bit rusty. Also mounted the gascolator and oil filter block

  Oct 05, 2019     Oil tank       Category: Engine

As my engine is a dry sump, a separate oil tank is required. The engine needs 2.64 gallons of oil, plus an airspace . I designed the tank to reside over the top of the engine mount. It's made out of .08 6061 aluminum.

  Sep 17, 2019     Engine hung       Category: Engine

Big day today, as the engine was hung.

I'm using a Rotec R3600. I realize many will recoil at that prospect due to negative reports about the engine that are found on the internet. While I acknowledge these reports, I am also making note of those that have the engine and are quite pleased with it. I appreciate those that have reported problems, as well as their solutions. I also appreciate Brian Kelly of Radial Conversions who supplies add on components that improve the functionality of the engine.

My main takeaway from all the research I have done on the engine is to make sure it is treated as the round engine that it is. There are care and maintenance issues that must be adhered to. I am not saying that those that have had problems did not do so, but I have come to realize you just can't operate this engine as though it were a flat four.