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Archive for the ‘Fuel Distribution’ Category

Oil Cooler & Aux Tank

With easy access to the inside of the oil cooler ducting, I used a little clay to radius the corners of the box. This is a pretty simple layout, but it still takes time because once you place the glass, you’ve got to wait a day or so for everything to cure.

Once I was pretty happy with how the diffuser box was going to mount to the oil cooler, it was time to bond the tubes to the cylinder intake plenum. I had originally considered making the tubes detachable from the plenum, but decided this wasn’t necessary.

Since the front half of the assembly hasn’t been bonded into place, I took advantage of the good access and applied a few layers of cloth to smooth the opening.

I decided to continue the tube to the front of the intake plenum to make sure the cooler received plenty of air. I used modeling clay to establish the shape.

It was a little difficult applying cloth and resin to the inside of the cavity, but you can see in this picture with the clay mold removed, it actually came out pretty good.

I made extensive use of my Dremel tool with the cone-shaped grinding stone attachment to smooth the rough edges of the fiberglass layup. With this portion completed, my next goal will be to join the front half of the intake to the rear half.

Keeping in mind that all of the stuff I’ve described above happened over the course of a few days, I’ve always found that it’s good to have something else to be working on while you’re waiting for resin to cure. I decided to start working on my auxiliary/ferry fuel tank. This is the big block of foam I started with.

I cut the big block of foam to the approximate size and shape and then added a few pieces along the edge to minimize the amount of filler I’d have to use to achieve the final desired shape. I glued the block of foam to the seatback so that I could test-fit the seatback to make sure everything fit.

Once the block of foam had been sanded to final size and shape, I applied Bondo to the foam. Bondo sands well and can be painted. My standard practice is to finish the Bondo as if it were going to be the finished piece. I sand and fill all the imperfections and then paint the Bondo so that (a) the fiberglass will release easier from the mold and (b) the finished surface of the fiberglass part will be very nice right out of the mold–minimal, if any, sanding.


Fuel Vent & Cowling

I guess I didn’t take a picture of it, but I finished the installation of my new fuel vent system. To recap, I somehow messed up my originally installed fuel vent system such that I was losing approximately 20% of my fuel capacity. When you’ve only got 3 hours fuel to empty, 20% loss is not an acceptable situation. The significance of this picture is (a) it’s related to the fuel system and (b) more importantly, it means that there’s hope I’ll be able to run auto gas after all. This Shell station in Ft. Collins claims that their 91 octane fuel doesn’t have Ethanol. I’ll test it to be sure, but I’d love to be able to run 91 Octane auto gas for $2.83/gallon rather than the more expensive 100LL. I’ll need to run 100LL for the first 25 hours engine break-in anyway, but after that, I might be good to go!

I am EXTREMELY happy to report that the paint shop called today to say that my cowling is finished. I picked it up this afternoon and it looks FANTASTIC. I think this cowling will absolutely make the airplane whole. Honestly, maybe it’s because I’ve been staring at it day in and day out for the past 6 years, but the mostly silver paint job seems boring to me. I think the checkerboard and red nose will add just the right amount of pizazz! Stand by for pictures of the completely assembled bird… Maybe tomorrow, we’ll see.

I knocked off at the airport a little early today to go on a motorcycle ride with a few friends from here in Loveland. We drove approximately 20 miles to the southwest to the small town of Lyons for sandwiches at a blues bar. A good time was had by all and I enjoyed the diversion. My bike is the one in the middle. Mine is a K1100LT and the other two are K75’s. They’re all about the same age. Mine’s a 1996.


Baffles, Primer, Manifold Pressure

It’s been long enough since I’ve posted an update that I actually had to go read my blog to see where I’ve left off. I have to laugh because less than a week ago I mentioned how it was warming up and I couldn’t wait to ride my motorcycle. It snowed yesterday and today. Welcome to Colorado, I guess.
In any case, here’s a shot of my newly-painted baffles installed on my engine. I think they look nice.

I’m using the standard bulkhead pass-throughs for my ignition wires. I installed nutplates in my cylinder barrel baffles to accept these pass-throughs.

I finally remembered to bring the Garmin 496 from home. It was one more thing I needed to install before I could button up the wiring and put the forward fuselage skin piece on for good. I think the panel looks nice all lit up like this. I need to make some labels…

I’ve been trying to verify the operation of all my instruments before I close out the top skin covering the fuel tank and the backside of the instrument panel. I was suspicious of my manifold pressure gauge so I called UMA this morning. My gauge is an electronic version–meaning it uses a transducer and wires rather than an actual manifold pressure line running to the gauge. My gauge was pegged at full scale showing 35+ inches of Mercury. I thought it should read ambient pressure which (at 5,000′ field elevation) should be somewhere around 25 in. Hg. Sure enough. UMA confirmed that my instrument was not reading correctly.
I spent HOURS digging through wires and breaking bundles of wires apart to test, probe and verify everything I could think of. I called UMA again and mentioned told them what was going on. He said it sounded like I was feeding 12 volts to the 0-5 volt sensor wire. This would cause the needle to go full-scale rather than reading ambient. I ended up pulling the gauge from the panel and bench testing the setup. Same results.
I started taking voltage readings from everything I could think of. I called UMA again and started telling him voltage readings. He determined that my gauge was calibrated incorrectly. It was calibrated for a 0 to 70 in.Hg. scale rather than the correct o to 35 in.Hg. scale. He had me pull the gauge apart and turn the trim adjustment until my gauge read 25 in.Hg. It was a little scary tearing apart a brand new gauge, but it turned out to be no big deal.
The whole ordeal consumed about 6 hours of time today. It also pretty well sucked the life out of me so I had a hard time getting motivated the rest of the day.

One of the little clean-up chores was connecting the capacitive fuel probe to the UMA fuel gauge. In the process of verifying the correct operation of my fuel gauge, I discovered a bad connection in some other wiring. After about an hour, I finally finished this 10 minute project!

For a simple little no-gyro VFR-only panel, I sure wound up with a bunch of little wires! I did my best to tie everything up and support it so I won’t be having intermittent electrical problems.

I made the final connections today for my electric primer pump and fuel solenoid. I decided to go with an electric primer system to avoid bringing the 1/8″ copper lines carrying fuel to and from the manual primer plunger valve. Since the aircraft doesn’t otherwise have an electric fuel pump, I installed this Facet pump just for the primer. The primer pump sucks fuel from the gascolator and then routes it through the fuel solenoid. I’ve got it set up so the solenoid opens at the same time the pump comes on. They’re both connected to a single, momentary contact pushbutton switch. Getting the right amount of prime will depend on holding the button down for the right amount of time. One-Mississippi, Two-Mississippi, etc.

This will be the next project: routing my spark plug wires. I spent the money for a “custom” harness for my O-200. Well, I’m not sure what makes it custom. From all I can tell, the wires are all cut to random lengths and I’ll wind up with just barely enough in some instances and way too much wire in other instances. I’m experimenting with circuitous routing to take up some of the excess wire. I still need to check on some internet forums to see if it’s possible to trim these babies down to size.

I installed the canopy so I just had to take a progress picture. Getting closer… I installed a string system to keep the canopy from springing open too far and damaging the hinge attach point. I was trying to come up with all kinds of spiffy brackets and mechanisms to hold the canopy open, but in the end I just decided to keep it simple and use a length of black nylon rope. Light, simple and effective. It’ll do.


Baffles, Primer, Panel, Canopy

The good news is that rattle can primer and paint strips very easily with Aircraft Stripper. The bad news is that I spent 2-1/2 hours this morning proving this. I purchased some Ace Hardware hi-temp gloss black and sprayed it over the top of my SEM self-etching rattle can primer. The two didn’t get along and I had to strip all the baffles back to bare metal.

It took about 2-1/2 hours to strip all the baffles back to bare metal. To avoid any compatibility problems this time around, I bought Rustoleum primer and Rustoleum gloss black. It worked out very well and I’ve now got a bunch of shiny baffles hanging from my hangar door while the paint cures. I probably won’t be back out to the hangar until at least Wednesday of this week so I’m hopeful they’ll have time to fully cure.

I wasn’t happy with the routing of the copper tube for my primer system. I visited the airplane aisle at Ace again and purchased 5 feet of 1/8″ copper tubing for $1 per foot. I have no idea whether this is more or less than what Aircraft Spruce charges, but I don’t really care. It was nice to buy the stuff locally and finish the project. I routed the line out of the primer solenoid horizontally across the firewall and then followed the engine mount to the center of the case just inboard of the left upper engine mount.

I also covered the copper line with clear rubber tubing from a oxygen cannula that they used on my Mom in the hospital. They were just going to throw it away so I snagged it. It sure made it simple to tie the copper line wherever I wanted without worrying about chafing. You can see that I also included a loop for strain relief just forward of the engine mount. I figure there’s a good possibility that there will be a little movement between the engine mount and the engine.

I took the canopy to the airport with me this morning. It had been sitting in my living room at home since I finished the Micro Mesh process a week or so ago. A friend, who’s far more experienced than I in terms of building airplanes, predicts that it’ll take me another couple of months before I’m ready to fly. I was hoping to be finished before that, but who knows… I’ll need to cover my nice, clear plexi so I started by running a strip of fine line tape along the perimeter of the plexiglass. It shouldn’t screw up the plastic or leave any residue the way that masking tape sometimes does.

I then covered the canopy with masking paper to protect the glass. It’ll be a big milestone when the day comes to remove the paper.

Here’s a shot looking into the cockpit with the panel mostly installed. I forgot to bring the GPS from home or I think I would have finished the entire panel installation. I’ll need to order the graphics to label the panel from Aerographics sometime soon. For the unfamiliar, Aerographics is a great company for all sorts of custom vinyl work for airplanes or other applications. I’m very lucky in that they’re local and have lightning fast turnaround if I need it. I’ll probably go see Marilyn sometime this week.

Here’s a shot of the current status of my panel installation from the backside. Don’t be too critical just yet. I’ve still got to install the GPS and its mounting bracket. I’ve got a couple of hard points built into the GPS bracket where I’ll use a couple of Adel clamps to firm up my wire bundles. It’s amazing how busy a fairly simple VFR panel can get.

Here’s an overal status shot taken just as I was ready to leave the hangar this evening. I just laid the black forward fuselage skin in place to see what it will look like. It’s pretty exciting to see the project taking its final shape. I think installing the newly-painted black baffles along with the plenum, routing the ignition harness wires and installing the canopy will make a huge difference. I can’t wait until the day comes when I can roll it out onto the ramp and give it a good wash job. It’s accumulated a fair amount of dust over the past few months. I’m sure it will also require a light polishing to remove some hairline scratches in the clear coat, too. Oh well, a labor of love!
I’m scheduled to give 6 Beech 1900 checkrides over the course of the next 3 days. With this much going on, I sort of doubt I’ll make it to the hangar much this week until maybe Friday. My vacation from Frontier is coming to an end and I’ll have to go to work for 3 days starting on Saturday. I’m nearly out of clean clothes because I’ve been spending so much time at my hangar so I may have to play Danny Domestic on Friday rather than going to the airport. We’ll see how much I can accomplish in the evenings over the next few days. i’d really like to get another day at the shop in before I have to go back to work. Stay tuned!


Baffles and Tank Installation

The weather has been absolutely freaky around here lately. It starts off looking like it’s going to be 70 degrees and sunny all day and then sometime about mid-day, it turns cold and windy and starts raining. In the late afternoon, the skies clear, the sun shines and it actually gets warmer. Oh well. The reason I’m telling you all this is that I was hoping to prime and paint all the metal pieces of my engine baffling today. I primed them with no problem, but then kinda got weathered out on the actual painting. As it turns out, the paint I picked wasn’t performing well anyway so I’m going to have to strip everything back to bare metal and start over tomorrow. Bummer.

Knowing that access is much more difficult once the tank is installed, I took a bunch of pictures showing how things are installed before I inserted the tank. Here are my throttle, carb heat and mixture cables along the left side of my cockpit.

I changed out my Home Depot tye wraps in favor of the heavy duty wire ties that came with my Click-Bond fasteners.

$140 worth of firewall pass-throughs. The top one is aluminum. The other 3 are steel. I went with the aluminum because I needed a big hole for the wire bundle that wasn’t available in the steel pass-throughs.

My power bus system. The one on the far left in this picture is my avionics bus. The center is the main bus and the right is my main ground bus. I plan on editing this photo to add labels showing what’s plugged in to where. I have all my wiring information stored on my computer in spreadsheet format. Every wire has a number.

This was today’s little “challenge.” Installing this fuel line was a pain in the tookus. For those of you who haven’t seen me in person, let’s suffice to say that I’m not shaped like a gymnast and/or contortionist. In fact, I’m shaped more like a left tackle from a college football team. To make matters worse, I had planned to use a 45 degree AN fitting from the gascolator through the firewall to attach to this hose. Well, the twist of the 45 degree fitting wouldn’t work out for me so I ended up going with a straight fitting. Not only did I have to steal the straight fitting off my fuel flow transducer, I also discovered that the lack of the 45 degree bend meant that my fuel hose was now approximately 2 inches too short! Arrgh!. I checked with one of my friends at the airport. His hose stretcher was out of service so I had to fabricate a new hose.

If I ever have to remove this hose again or this Adel clamp holding the hose in place, I’m going to go steal one of my brother’s daughters to do the deed. One of them is 5 foot tall, 80 pounds and smart as most adults. The other is a 42 pound 2nd-grader who also happens to be into competitive gymnastics. Ah, the cycle of life. Kids come along just about the time I’m too fat and too stiff to fit into these tiny places!


Spinning the Spinner

I woke up to snow this morning. Gotta love springtime in Colorado. I started the day by going to the hospital to visit my Mom at about 8:15. She’s recovering very well. I can’t believe she’s climbing in and out of their simulated car and up and down some stairs in the physical therapy room only 2 days post surgery. Amazing.

I left at about lunchtime and decided to visit the paint shop to see how they are coming on my parts. Our agreement is that my work is filler work for them so they’ll do it when they don’t have their usual flow of automotive work. We’ve worked under this arrangement in the past and they’ve always treated me very well. If anyone in the area needs any paint work, I highly recommend Choice City Auto Body in Ft. Collins, CO.

Since I’m getting closer to starting the engine, I asked the Choice City guys if there was any chance my spinner and backplate were painted. As it turns out, they had everything ready except for the cowling itself. I went straight back to my hangar with my CR-V full of freshly painted parts and installed my backplate, propeller and spinner. The spinner looks a little out of place without the cowling, but it should look great once the cowling is installed.

Mark and the guys at Choice City went the extra mile and even painted the back of the spinner backplate black and white. Very cool. I’ve dealt with other paint shops in the past who didn’t care about the big stuff, much less this kind of detail work.

I received another package this afternoon from Aircraft Spruce. It contained the mounting bracket for my primer solenoid along with the Facet electric fuel pump I’m going to use for my electric primer system. I spent a little time this evening running copper tubing for the primer system and mounting the pump and solenoid on the firewall.

My new ECI cylinders have primer ports in each cylinder just like Lycoming engines. I decided to prime two cylinders by splitting the primary input line using a steel “T” fitting. The Adel clamp fits nice and snug around the nut from the primer fitting. I started at the “T” and then worked my way back to the primer solenoid on the firewall. I covered the primer line with rubber tubing and then wire-tied it to the engine lifting bracket. I tied it to the lower half of the bracket so I can still lift the engine without having to move the primer line.

I used my string tie technique rather than Tye wraps. I also padded the tubing with clear tubing.

I put a loop in the tubing as it approached the firewall to allow some “give” for vibration. The whole mess is still a little “bouncy” so I will probably end up adding another Adel clamp on the firewall to stiffen things up a bit.

I’m using an Odyssey 680 battery and have no alternator or generator to charge the battery. I’m planning to just charge it up after each flight. There are many opinions as to the best/most appropriate battery charger for this application. Rather than wade through all the various opinions, I ended up just sticking with the Odyssey-brand charger. This particular unit provides up to 12 amps for a quick charge but also has “smart” capabilities where it automatically reverts to a maintenance phase when the battery is fully charged.


Primer, Manifold Pressure, Adel Clamps

My new-style ECI O-200 pistons have primer ports on each cylinder. I decided to go ahead and prime at the cylinder rather than just north of the carburetor in the intake spider. Updraft carbs are somewhat notorious for the possibility of an engine fire due to over-priming. I think it’s a little less likely when the prime is going directly to the cylinder. I’m going to prime 2 cylinders and then use another primer port for a line to my manifold pressure transducer.

Rather than cluttering up my firewall, I decided to mount my manifold pressure transducer using an Adel clamp on my engine mount. I’ve used Adel clams for a few things here and there in the past and have always cussed how hard it is to get them lined up and the bolts installed. Trying to get two clamps lined up is darned near impossible. I purchased this special modified vice grip tool specifically designed for Adel clamps. It comes with an awl that you use to get the holes aligned. Once the awl is in place, you use the vice grip tool with its forked jaws to squeeze everything together and hold it in place while you remove the awl and replace it with a bolt. It works VERY well and is worth the ~$30 it cost me!

This is an overhead shot of my primer lines running from a T-fitting to 2 cylinders. The other copper line you see at the lower left of the picture is a manifold pressure input to my manifold pressure transducer. I haven’t run the primer input line to the T at this point.

I started working with my firewall pass-throughs today. The firewall has a few extra holes in it from the original builder. I’ll do my best to make use of existing holes with the idea that I’ll cover them once all my pass-throughs are complete.

I received my Aircraft Spruce order containing the steel fittings for my fuel flow transducer. JPI spec’d steel fittings so who am I to question the experts. They cited a concern for galling problems with aluminum AN fittings. It’s hard to tell in this picture, but I managed to break the glue bond on my transducer bracket where it is [supposed] to be attached to the oil tank. The failure mode was interesting in that it basically sheared between layers of paint. The good news is that once I installed the hoses, the bracket is pretty much held in the same place as if it were glued. I’m going to re-glue it using a fresh batch of JB Weld. I’m kind of wondering if my original attempt was hampered by an old, less-effective, tube of JB Weld.


Hose Fabrication & Transducer Bracket

I decided to fabricate my own fuel lines out of Aeroquip 303 hose and Aeroquip 491 hose fittings. The EAA has a nice video tutorial and I thought I was good to go. It was a little more difficult than I had hoped.
I learned a lot as I went along. I’ll share the following tips if you want to try it for yourself:

  • Use tons of lubricant. Pick the slickest stuff you can find. I used Tri-Flow and motor oil. I think WD-40 might work just fine, too.
  • Once you’ve got everything set up and you’re ready to start threading the mandrel into the hose, you might try tapping lightly on the end of the mandrel until the shallow metal threads start tapping lightly against the metal of the gold sleeve. This way, when you start pushing and turning, you know you’re about to have thread engagement. Don’t bang too hard or you’ll damage the threads! Just a tap or two.
  • Don’t be afraid to back the mandrel out if it gets really hard to turn. I’d do this rather than continuing to crank the mandrel down tighter against the hose nut. Just back it out, apply additional lube and screw it back in.

Here are a couple of my completed hoses. I buggered up the fittings a little bit, but these were used fittings to start with so I didn’t put all the scuffs on them!

The official dip for fire sleeve is quite pricey at about $130 per quart. On the advice of a friend, I thinned a glob of high-temp RTV using lacquer thinner. It didn’t mix perfectly, but after sitting for a few minutes, it was at least acceptable. I made it a point to stir the mixture a little bit before I dipped each end of the hose. You can see that it wicked up in the hose pretty well.

I’m installing a JPI fuel totalizer. The installation instructions state that the fuel flow transducer should have something like 6 inches of straight flow before and after the transducer. Not gonna happen in my installation. With a gravity flow system, I don’t want to be routing fuel all over the engine compartment just to have 6 inches before and after the transducer. Instead, I just did the best I could and kept the fuel hoses fairly simple. I’ve seen installations that are far more “bendy” than mine and the owners claim their fuel flow system is still very accurate. I fabricated the yellow bracket as a mounting pad for the transducer. I glued it to the kidney-bean-shaped tank using JB Weld. I actually think it turned out quite well. I hope it works! [Oh. Before somebody scolds me… I am planning on using steel fittings as per the JPI instructions. The blue aluminum fitting was temporary for initial hose measuring and fitting. I’ve got steel fittings on order from Aircraft Spruce.]

This is the tool to install the stainless band clamps to secure the firesleeve. The tool was $18.65 and each stainless band cost $2.20. I didn’t price it out, but I’m betting I bought all the tools and supplies to make the hoses and still saved a little money. By using the proper tools and taking my time, I’m pretty certain I achieved an acceptable level of quality and saved a few bucks. On top of all this, it was very handy to be able to make, test fit, and re-make the hoses as necessary to achieve a perfect fit.

This is a close up of my finished banding at the end of the firesleeve. You initially bend the band at a 90 degree angle before you cut the band and remove the banding tool. I then tapped the band tight against the sleeve with a small hammer and cut off the excess band using a Dremel with a cutoff wheel. I tapped a little more with the hammer and then polished away the rough edges with my Scotchbrite wheel. I’m pretty pleased with the results.


Paint, Gascolator and Transducer Bracket

February 16, 2010. The time had finally come. I’m finished with all the sanding and filling on the remaining fiberglass pieces and they’re ready for the paint shop. I tried my hand at painting, but quickly realized I’m no good!

These are the parts and pieces of my gascolator. It was looking pretty ratty so I decided to blast it in my bead blasting cabinet and apply a little rattle can paint. It’s funny how when everything else is shiny and new how something like this sticks out like a sore thumb.

I decided I needed to fabricate a new bracket to hold my fuel flow transducer. At this point in the project (for good or for bad) I seem to have plenty of scrap aluminum lying around my shop.

Here are the gascolator parts after the strip and repaint. I’m hoping this won’t look so out of place when mounted on my freshly-painted white firewall.

Sorry some of these posts don’t fall neatly into a single category. At this point in the project, I’m no longer focusing on a single area in any given work day. It’s more a matter of wrapping up all the loose ends and keeping everything moving forward at once. That’s why pages like this are tagged with several different categories.