Details
Hits: 2123

Sunday I spent most of the day at the hangar. I redid the magneto timing, and now the engine sounds happier when running on mag only. I tried using my ancient automotive timing light to confirm the mag timing, but it didn’t seem to be working. I bought a new timing light, and found that while it worked on the electronic ignition, it would not trigger the strobe on the mag. Maybe the shielded plug wires are interfering with the inductive pickup. Maybe that old timing light was serviceable after all.

I had Dale Lamport, a local multiple RV builder sit in the cockpit while I tried to check the EI timing, but the sunlight was so bright that the timing marks were only very dimly visible. The timing appeared to be fairly close, but I probably should try it again just before sunset some day.

I also put safety wire back on the prop flange bolts. I installed the compass error placard, and corrected some setup errors on the EIS 4000 engine monitor. And, I did a test of the data recording from the engine monitor, EFIS and GNS 430. I found that I had somehow managed to delete a critical function in the engine monitor recording script - fortunately I use a version control system, and was able to dig back into the earlier versions and repair the damage.

Details
Hits: 2985

Yesterday afternoon I got the compass swing done. In principle, it should be done with the engine running, but I need to minimize ground running time as the engine is not yet broken in. So, I did it with the engine off, but the avionics system, strobes, etc powered. I’ll do another compass swing with engine running once the engine is broken in. The flux valve for the Dynon EFIS is in the rear fuselage, so I’m convinced it would not be affected by the engine.

The Dynon EFIS compass had extremely low errors after doing its calibration procedure. The errors on most headings were either zero, or one degree, with only two headings having two degree errors.

The standby compass was not so accurate, as it is apparently badly affected by magnetism in the steel roll bar. I have a line on a degaussing tool, and I will give it a try sometime after first flight. CAR 605.14(d) requires

a magnetic compass or a magnetic direction indicator that operates independently of the aircraft electrical generating system

For now, the way I read CAR 605.14, the magnetic compass in the Dynon EFIS is sufficient to meet the requirements, as I have the internal battery, which allows it to operate even if the aircraft electrical system is dead.

There was a C172 doing circuits, so I was able to get a radio check on both the GNS 430 and the Microair 760. The Microair 760 is hooked up to an antenna inside the left wing tip, which will provide less than optimum performance (but zero drag). I was encouraged that the pilot in the C172 said the signal was strong and clear. It will be interesting to hear how it does with longer range reception and transmission.

I'm relieved to get the radio checks out of the way, as there would have been an awful lot of wiring to troubleshoot if things hadn't worked - two radios, each with several wires going to the intercom box, several wires between the intercom box and the headset jacks, plus two antennae, etc.

Details
Hits: 3466

Success! The engine runs, finally.

I took the afternoon off to make yet another engine run attempt. I put the new battery charger on the battery for 90 minutes to make sure it was fully charged. Then I did a fuel flow test to be sure that I had adequate fuel flow at the fuel injector. I disconnected the fuel line at the fuel injection servo, and put it in a gas can. I ran the boost pump for one minute, and used a calibrated fishing scale to determine the weight increase - 4.5 lb, which equates to a fuel flow of 45 USG/hr. Way more than enough. I need to do the official fuel flow test later, with the fuselage pitched up to the maximum climb angle - but I am certain that it will make the requirement of 125% of the fuel flow required at take-off.

Then I pulled the aircraft out of the hangar and chocked it. The engine caught on the second cranking attempt. All the engine indications looked good, except the alternator load meter - it showed 5.2 amps load with the alternator switch OFF. I need to review the settings in the EIS for that one. The bus voltage did not increase when I selected the alternator ON, but I later discovered that the alternator field fuse was not installed, which almost certainly explains this snag.

After warming the oil, I ran it up to 1800 rpm and cycled the prop. It took a whole bunch of back and forth on the prop control before the rpm would respond. But, that was expected, based on reports from other builders.

The engine ran smoothly on the electronic ignition only, and with both the magneto and electronic ignition ON. But it ran a bit rough on magneto only, and the EGTs were higher. It seems probable that the mag timing is too retarded. Talking with Ron M. (Aircraft Maintenance Engineer based at Smiths Falls), it seems that perhaps I erred by trying to do the mag timing without having the pin that Slick calls for to lock the mag internals in place. I had assumed that as long as the mag breaker box light goes on and off at the correct crank angle, that everything would be OK. Ron gave me a spare Slick mag timing pin, and I’ll have another go at setting the mag timing tomorrow.

Life is good - I flew the mighty C182 this morning, I got the first engine run in this afternoon, and now I’m sipping a glass of wine and watching the first Canadian Football League game of the season (real men only need three downs to get it done :).

Thanks to everyone who e-mailed and phoned with advice on starting procedures. I appreciate your support.

Details
Hits: 2752

It's getting a bit tedious writing these "still haven't started the engine" posts, but it is what it is.

Yesterday I spent about 10 hours at the hangar. I assembled the borrowed, modular, engine hoist and removed the prop. The flywheel refused to come loose - one of its holes was a really, really tight fit on the prop bushing in the crankshaft. I made a trip into town to buy some penetrating oil and a rubber hammer. A bit of penetrating oil and some gentle taps from the rubber hammer did the job.

I then checked and rechecked to be sure I was putting the flywheel back in the correct orientation. There was an "O" next to one of the prop bushing holes on the flywheel that was supposed to line up to an "O" on the crank. I couldn't find any "O" on the crank, so resorted to putting the #1 piston at top dead centre by feeling in a spark plug hole, and putting the top dead centre mark on the flywheel in line with the crank case.

Putting the prop back on is a bit fiddly, as you can only turn each captive prop bolt a bit before another prop bolt end hits the prop hub. You have to go round and round, from bolt to bolt, turning each one a bit at a time.

I couldn't find my prop bolt torquing adapter - I had looked for it at home the night before, couldn't find it, so I assumed it was at the hangar. But I couldn't find it at the hangar, so that meant one more trip into town to the hardware store.

I just finished torquing the prop bolts when Dan from Canadian Airmotive Avionics showed up to do the transponder to altimeter correlation checks. That took about an hour, then I had a late lunch.

After lunch, I spent a good long time getting the mag retimed, then the same with the electronic ignition. Then I tracked down someone to be fire guard while I tried another engine start.

The first time I tried an engine start, I ended up with quite a bit of fuel that later drained out of the sniffle valve in the bottom of the induction manifold. I interpreted that as a sign that I had flooded the engine. So, this time I was perhaps a bit too cautious with the fuel. The engine fired several times, but I never succeeded in getting it to run. The fire guard said he thought it needed more fuel. But, the battery ran down pretty quickly, so I had to stop.

The battery seems to have a lot less capacity that I expected. I had completely drained it twice during the construction phase by forgetting to turn the battery master switch off when I was finished testing something. I had planned to replace the battery before I started the night and IFR phase, but I have decided to order a new one now.

Also, I did some investigation into the battery charger that I have been using. I compared its specs against what Odyssey, the battery manufacturer, recommends, and found that this charger (Battery Tender Junior), isn't even close to the recommendation in their "Technical Manual". And, it seems that my charger is putting out even less voltage than its spec sheet says it should. It looks like the battery has not been getting anywhere close to fully charged, and it may be a dodgy battery at that. So, today I bought a much nicer battery charger, recommmended by Odyssey, an ACI BCSC 7a.

It looks like I've been fighting perhaps four different issues:

  1. Ignition timing problems caused by flywheel angle error - fixed.

  2. Inadequate battery charger - new charger purchased today.

  3. Possible low battery capacity, which limits the number of start attempts - new battery ordered tonight. I may cobble together a temporary external power cart connection, as one of my hangar mates has a golf cart with an external power cable.

  4. Pilot who isn't yet sure what exact start technique his engine likes - I've received lots of good advice from several builders, plus I've looked at many POHs for type-certificated aircraft with this engine.

I was a bit bummed out last night, which is why I didn't update the web page with yesterday's story. But, I'm happier today. This aircraft has been over ten years in the making, and I'm almost there. A few days more delay to fight with this engine is nothing in the big picture.

I'll be going back to the hangar after lunch tomorrow. I'll throw the new charger on the battery, and give a couple of hours to top things up. Then I'll have yet another go at starting this blasted engine (assuming it isn't raining).

Details
Hits: 2649

This is a classical good news, bad news story. The bad news is that I made another attempt to start the engine today, and I did not succeed. The good news is that I discovered what the problem is.

When I tried to start the engine I noted that it kicked back when the magneto fired. Not good. I tried again, this time using the electronic ignition. It kicked back again. I stopped, and pondered what common cause could cause the timing for both the magneto and electronic ignition to be advanced. I pulled the top spark plugs out, and using a small screw driver in the number one plug hole, determined that the piston reached top dead centre 60° after the marks on the flywheel said it should.

I took a quick look at the starter, and couldn't see any damage from the kickbacks. I'll take a closer look tomorrow.

Thinking back, I had the flywheel off at one point. I thought I was careful to reinstall it at the same angle that it had been removed, but I obviously screwed that up. I borrowed an engine hoist to sling the prop from, and I am taking a day off work tomorrow. I think I should be able to get the prop off and on, and the timing reset tomorrow. If we get a break between showers I will make another attempt to start the engine.

I had three other RV-8 builders contact me with advice on engine start. Two of the three said that their first attempt was a failure too. They each told me what start procedure they use - all three were different. This morning I spent a few minutes in our technical library, looking at the Pilot’s Operating Handbooks for various aircraft that have Lycoming IO-360-A or -C series engines - Beech Sierra, Cessna 177RG, Mooney M20F, Partenavia P68C, Piper PA-28-200R and Socata TB200. Their recommended start procedures were all different, and none of them were exactly the same as what Lycoming recommends. This is a testament to how finicky these engines can be.

Details
Hits: 2907

I was on the road for most of the week, so today was the first chance I had to go to the hangar since Monday.

The big task I wanted to get done today was the first engine start. In the morning, I tidied up some loose wiring ahead of the firewall, and found ways to secure all the plug wires. I secured the Bowden cable for the alternate air door, to keep it from rubbing on the plug wires.

Then I pulled the two Mooneys out of the hangar, so I could get the RV-8 outside. It felt really, really good to finally have the aircraft outside. I put some avgas in the fuel tanks, then tried the boost pump - no fuel pressure - it was not managing to pull any fuel. This was an expected problem, as apparently the seals in the Airflow Performance boost pump dry out. About this time I realize that there was a major fuel leak in the cockpit. I discovered a fuel fitting that was very, very loose.

I disconnected the fuel line from the input to the fuel injector servo, then put a piece of flexible hose over the fuel vent from the left fuel tank, put the fuel selector on the left tank, and gently blew in the fuel vent line to push some fuel up to the boost pump. I selected the boost pump back ON, and immediately heard the sound change, as it was now pumping fuel - a stream of fuel was pumped out the disconnected fuel line. I stopped the boost pump, and reconnected the fuel line.

Next, I needed to crank the engine to build oil pressure before attempting a start. I removed the upper spark plugs, then cranked - the display on the EIS 4000 engine monitor died when I cranked, as the voltage dropped too far. But, the LOW OIL PRESSURE red light in the annunciator light group, is driven by an independent pressure switch. It extinguished after about 15 seconds, indicating that the oil pressure was greater than 15 psi. The display on the EIS 4000 came back to life as soon as I released the starter, and it showed 25 psi of oil pressure.

I pulled the aircraft out onto the taxiway in front of the hangar line, and chocked it. I grabbed my test card, climbed in the aircraft and strapped in. I ran through my test card, and got to the point where I was to attempt to start the engine. The engine fired, but I was too slow to get the mixture control to full rich, and it died. I cranked again - nothing. I reprimed it, and cranked again - it fired again, then died. I couldn’t get it to fire again, and the battery eventually started to run down, so I stopped. I pulled it back into the hangar, and put the battery on the battery charger.

Reviewing the sequence of events, I realized that I had made several errors. First, I had not taken the time to review the engine start section of the Lycoming Operators Manual. I had simply used the checklist I made, which was effectively a translation of the procedure in the manual. But, looking at the manual again, I see that I was way too slow to push the mixture forward. And, when I tried to reprime the engine, I now realize that I had left the throttle back, rather than pushing it full forward, so very little fuel would have flowed.

Assuming the rain holds off tomorrow, I’ll try again in the late afternoon. Meanwhile, I will read my collection of e-mail list messages about start techniques for Lycoming engines with Bendix fuel injection systems. The start procedures are quite different from the ones for carburetor equipped engines that I am more used to.

I was really looking forward to the first engine start today, but I'm not too bummed out, as I got fairly close. The big event should happen sometime this week.