Not So Fast, Buddy Boy

Or, should I say "It's not ready, till I say it's ready".

The weight & balance is done, and I was glad to see that it came in at 696 pounds, even with all the stuff I added, including extra batteries, heavier paint job, and TWO paint jobs.

I thought I just needed to get the vinyl lettering applied and a few more little items, when go taxi. But, why should it be that easy?

I thought I'd celebrate having the canopy on by running the engine a little. I got it up to 2,400 RPM, then it started getting rough again. What's the deal with that?

Rats.

Maybe that sensor bracket is still vibrating a little. I have a plan for that. Maybe the mixture still needs tweaking. I dunno.

We'll see tomorrow.

Anyway, here's some photos of the mostly complete engine installation.





Mixture look a little rich?

So Close I Can Taste It

I am 90% though my annual condition checklist and the thing is close to being ready.

Yesterday, I hauled it over to AvTech for weight & balance. I had the help of the instructor, Karen and two A&P students, Tom & Colin. I forgot to use my camera, but Colin grabbed these with his cell phone. Thanks folks!


I was happily surprised to see it come in under 700 pounds, 696 pounds, to be exact. I was afraid I would be in the 725 range, so 696 is good, considering all the stuff I've added. We weighed all possible combinations; empty, main tank, header tank, aux tank, pilot installed, etc. I'll figure all the arms & moments later.


Just to remind me that nothing should happen too easily, I intended to taxi the Q-200 over to AvTech for the weigh-in. Unfortunately, there was interference between my air induction tube and the cowling, which resulted in causing the lower cowl to bind against the spinner. So, today I'll have to modify the tube to better fit the cowl, blah, blah, blah.

Happy Anniversary

Today, June 22, 2009, is the 10th anniversary of my one-day trip across the U.S.A. in my Q-200. I guess it doesn't seem like ten years, then again, a lot has transpired since then (the best of which, was marrying Sandy).

Here is the link to the whole story Trip Across USA It's a pretty long read, so I suggest making yourself comfortable and pouring a cup of coffee first.

Here is the radar capture for June 22, 1999 - about mid-day. As you can see I had a bit of a time picking through Oklahoma.


It really is a shame that I can't celebrate properly and go fly today, but alas, I am still trying to hash out engine problems. (I think the engine now has more power than with the old system, I just can't get my back-up fuel injection to work yet). I guess I'll commemorate it by going to the hangar and giving the old girl a pat on the vertical fin.

This little plane has been one of the most rewarding, satisfying, challenging, expensive, hair pulling, bleeding, frustrating, and funnest things that I have ever been involved with.

Here's to my little Quickie!

I Got It ! - I Get By With a Little Help From My Friends

Finally... I know what was causing my woes (besides dain bramage). How long have I been working on this rough engine problem? Two months? Three months? Four?

The problem was finally traced to vibration of the bracket that holds the pickup sensors.

Now, how did I come to that conclusion?

Several of my advisers suggested getting my hands on an oscilloscope (see the previous post). After I sent out the results of that test, two experts said that my problem was the variation in amplitude in the signal - not a phase shift, and was most likely caused by vibration.


I got hold of Don Bartlett (who doesn't like me very much) and he welded a couple of gussets onto the new bracket made by Phil Lankford and Jeff Doddridge, in California.


When I first fired it up, I could tell that things were better, but still not 100%. It ran well on the mag, but not on the electronic ignition, but the fuel injection seemed fine. Fortunately, I had experience with this and figured it was just dirty spark plugs.

I let the thing cool off for an hour, pulled and cleaned the automotive plugs, then stuck them back in.

When I fired it up it ran just great! Wow!!! Did I say great? I really meant fantastic! I brought it up all the way to 2,370 RPM, which I hadn't seen in a long, long time! There was still a slight roughness when running on the electronic ignition, but nothing like before. I think I need some bracing of the sensor bracket, but at least I know what to do!

I want to thank all you guys who were helping me on this frustrating, teeth gnashing, hair pulling episode. I'm going to take a couple of days off for a Hoskins family reunion, but I'll be back at it on Tuesday.

Thanks again, all!

More chasing

Please take a look at these two sorrowful pages of sketches of today's oscilloscope output.

The engine always starts easily and idles very smoothly. Roughness starts around 1,800 RPM. Misfiring is very pronounced, really shakes the engine, and the exhaust is momentarily black.

Page 1.

First wave is pretty much what it looks like with both the 6" and 7 1/2" wheel, at idle. With the 7 1/2" wheel there is a little more of a hump in the middle of the trigger wave. The peak-to-peak amplitude is pretty even and is about 4 volts p-p.

2nd wave. This is what it looks around 2,000 RPM. Notice that the amplitude varies greatly, from about 3 V to 7.5 V p-p. We tried adjusting the air gap from .015 to .060 and didn't see a change here. We thought maybe the variations in amplitude might be from the prop bolts and flange lugs. Just speculation.
3rd wave. Another sketch at high throttle. Here, I tried to include the trigger wave. The trigger wave, at higher RPMs, always had a greater p-p voltage than any other part of the wave, while at idle, the trigger wave was the same.


Page 2.

There always is a consistent phase shift (skipping a tooth?) at any speed. In the sketch, I am attempting to show how it would bounce back and forth. We feel this is a key issue, but have no idea why it is occurring.

We also saw that the amplitude of the wave is pretty even at low RPMs, but at higher revs the amplitude varies a lot. Click on the sketches to better read the voltage ranges.


Other things we tried and noticed:

Changed from 1 1/2" to 6" wheel. no change seen on scope.
Removed the prop bolt closest to the trigger gap. - no change
Tried a smaller diameter sensor. - a little smoother.
Degaussed the crankshaft flange. - no change.
Ran on the single magneto only. - a little smoother.
An automotive timing light flashes consistently at low RPMs, but becomes intermittent, in sync with misfiring, at higher speeds.
Installed the 6" wheel and used the 7-1/2" sensor mount bracket. This caused the sensor to kind of be extended way out from the aluminum bracket. No effect.

I sent these sketches to Tracy Crook, at RWS and he thinks that the change in amplitude is the source of the problem and what I perceived as a "phase shift" is not an issue. Given that, I will be concentrating on eliminating all vibration in the sensor mount bracket.

Sam

Chasing the Noise

I have been corresponding with several of you and thought I'd put a week-end summary into one post. First off, I'd like to thank all of you for your help and patience while I'm going at this problem.

These things had a positive effect:

• Temporarily replacing the 1/2" VRS sensor with an old 3/8" sensor. Ran a little better.
• Centering the sensor over the trigger teeth. Got another 200 RPM and noticeably smoother.
  

These things had no observable effect:

Changing from a 6" trigger wheel to a 7-1/2" trigger wheel (photo attached), and sensor mounting brackets.

• Adjusting air gap from .030" to .055"

These things had a negative effect:

• Swapping the position of the primary and backup VRS sensors

This had an unknown effect:

• "Dressing up" the two tooth gap in the 7 1/2" trigger wheel. Actually, this was a bonehead move. I'm going to attempt repair it by having a pal fill it in with weld, then reduce it, so it pretty well matches the gap on the 6" wheel. The original configuration may help alleviate the phenomenon known as "phantom tooth".
  

This was a positive fix:

• Swapping my standard trigger wheel with Lynn French's aluminum bowl and trigger wheel setup.
  

This is what I know.

• When the engine is set at 6 deg. ATC, the primary sensor is directly over the first tooth in the gap. (photo attached shows the engine set exactly at TDC.).
  
• The air gap remains consistent all around the wheel, within a couple of thousandths.
• The engine starts easily and idles smoothly.
• When at about 700 RPM, the measured timing is around 38 deg. BTDC
• When running at full throttle (2,100 for now) the timing is about 25 deg. BTDC
• At high RPMs, the automotive style timing light flashes quite intermittently at the same time the engine starts missing, indicating, to me, that the signal is getting interference.
  
• Engine now runs pretty will up to about 1,900 - 2,000 RPM

This is next:

• Borrow an oscilloscope to view the VRS sensor signal.
• Repair the trigger wheel.
• Inquire into getting a duplicate bowl, trigger wheel and mounting bracket ala Lynn French.

Again, I invite suggestions and I thank you for the help.

Still Not Right

I am so frustrated. I just can't get the engine to run right. I started with a 6" trigger wheel and after much gnashing of teeth, I borrowed Lynn Frenches setup. I installed his parts, using my sensors, and the engine ran great. That much I know.

I figured my sensors were picking up noise from the rotating prop bolts and I hoped that a larger trigger wheel would help. (Please see the photos in earlier posts). I got a 7-1/2" wheel and had it modified by Phil Lankford and his buddy Jeff.

I didn't want to copy exactly what Lynn did, since he has a V-belt on his prop hub to drive an alternator. My alternator is on the pad on the accessory case.

Here's a couple pf photos of Phil & Jeff's parts.



I do have a couple of smaller diameter, and very used, electromotive sensors and I'll try rigging them up tomorrow, just to see if that makes any difference.

This sucks. Any comments, please?

Plane Progress - Slowed to a Crawl

Okay, Sam... What's the latest? Are you close to flying again?

Well, I am closer than before. Phil Lankford, in the San Diego area is working hard to get me a new trigger wheel and mounting bracket worked up. That should show up within a couple of days.

The new Bob Archer com antenna is installed, as is the remote compass for the Dynon D180.




Since I have gotten my system back-up battery installed, I should be able to permanently install the tail cone today or tomorrow.

My back-up fuel injection system is still buggy, but I have to get the engine running again before I can try that out.

So yes, I am getting close. When I get all the pieces back on and working I'll go through my entire Annual Condition Inspection checklist and make sure that I haven't left anything out.

One Reason Why Progress Has Slowed Down

On May 8th, a huge storm blew through southern Illinois. It wasn't just a thunderstorm, it wasn't an inland hurricane, it wasn't a tornado. It was a derecho, a term I don't recall hearing before. Read about it here: http://en.wikipedia.org/wiki/Derecho


I drove through the first wave as I left Murphysboro. I was half way to an airshow in Branson when Sandy called and told me they were getting blasted by the second wave, which the local weather guy called "the head of the comma". There were sustained winds of 90 mph and gusts over 100 mph.


Here is a technical description of the storm. Scroll down to May 10. http://www.weather.com/blog/weather/?from=blogredirect%3f


Here are a bunch of photos showing the impact. http://www.flickr.com/photos/thesouthern sets/72157618012419861/show/

We were without power for 6 days. Well technically, Sandy was without power for 6 days. I only was unconvinced for three nights because the first four I was staying in the Hilton in Branson.

Thousands of trees down, perhaps 2,000 utility poles broken and hundreds of utility workers from as far as Florida and Pennsylvania came in to clean up the mess.

We lucked out. Just a little damage to the gutter on the garage and a few tree limbs.

The big question is; How can we live in southern Illinois without a basement or storm shelter? How crazy is that?

Our house sits in what was the path of the 1925 Tri State Tornado, the worst tornado the nation has ever seen. http://en.wikipedia.org/wiki/Tri-State_Tornado Take a look at the photo of Longfellow School on the Wikipedia page. They never rebuilt the school but converted the land. Longfellow Park is about three blocks from our home.

While there was damage to some buildings at the Southern Illinois Airport, MDH, the T-hangars and the planes within them were unscathed.

I Finally Figured It Out

That's what my dad always used to say, "I finally figured it out". He was always talking about the meaning of life. In my case, I just want to figure out how to make the damn engine run.

Thanks to Lynn French, I definitely know the ignition problem is due to my trigger wheel and sensor assembly. Lynn was kind enough to lend me his parts, while his engine is down, and I bolted it on this afternoon. Lynn has the 7" trigger wheel, while I have the 6". I used my existing sensor and wiring.

The engine fired up just fine, as always. After it warmed up I ran it all the way to 2,320 RPM. I haven't seen the engine turn that fast and smooth in a year and a half. While I was at WOT I switched off the mag and the engine didn't miss a beat.

Here are some photos of Lynn's trigger assembly mounted on my plane. Compare them with my installation in my previous post, dated April 19.


So, without a doubt, the smaller wheel must be causing me to pick up noise from the crank flange and prop bolts.

That's the good news.

Now, I have to figure out what to do about it. My first inclination is to see if I can find a different sensor and use the existing wheel. I have a lot of $$$ in that trigger wheel, and looking at Lynn's parts, I'm sure he even has far more machining than mine. I know a rep for an industrial sensor company and I'll give him a call tomorrow.

Maybe I could use an aluminum plate, with the embedded magnets, like Klaus uses. I would have to know if that type of Hall Effect device would work with the EC3.



Any other ideas?

Figuring out the Electronic Ignition

Gee, no posts for a month. You'd think I wasn't doing anything. Actually, I've been stymied by the engine. The general symptom has been that I can't get full RPM. Before I started this conversion, I was getting 2,300 static RPM - now I can only get around 2,100, and it's rough.

Yesterday, I finally narrowed it down. The problem is definitely with my electronic ignition, and most likely my installation portion of it.

Yesterday, I ran the engine again, but this time I hooked up an automotive timing light to the #1 spark plug lead and kept the light in the cockpit to closely watch the flash and see what it was telling me. At low RPMs, idle through about 1,500, the flashes were nice and steady - just like when I did the Mode 8 check with the engine off.

However, as I started to raise the throttle, the flashes became intermittent.? It's as plain as day and I don't' know why it took me this long to see it. The faster the engine ran, the worse it got.

When I retarded the throttle, as I came back down to the 1,500 range the flashes on the timing light became nice and smooth again. So, now all I have to figure out, is why this is happening.

I still think there may be trouble in my 6" trigger wheel/sensor installation - possibly picking up noise from the crankshaft flange and prop bolt lugs. Lynn French's engine is down right now and he is kindly lending me his 7" trigger wheel and mount, and they should be here soon. Swapping those parts should quickly confirm or disprove that installation issue.

Air Intake mods - More Sawsall Art

I continue to plug away at programming the EC3 and things are getting better. The mixture plot is getting smoother and the engine is running better.


I have a fifth fuel injector, which is used as a back-up, but it barely ran. I found that it was over-sized, capable of delivering 87 lbs. of fuel/hour and the mixture was extremely rich. This seems to be out of the adjustment range of the EC3 so I ordered a 55 lb./hr. injector. It will be here next week, so in the meantime I am holding off on tuning the engine and will tend to a few other items on the list.

All along, I have been planning a radical change to my combustion air intake. This was successfully accomplished by Harry Hinckley and Greg Zimmerman in Greg's FAST Swearingen SX300. There will be a little scoop in each plenum snout. This air will be directed, through two hard tubes, to the throttle body. Here is a photo of the mock-up I made last year. I have since made the pipes, now I just need to get the scoops placed in the plenum.


As usual, I start with pouring in 2-part foam, held in place with paper dams & tape.


Then I get out my favorite shop tool; Mr. Sawsall:

I use the 14" saw blade to gently remove some of the foam I didn't want.

After rough trimming, I attached a couple of pieces of hard foam, using 2-part foam as glue. The hard foam will make a better foundation for the lip of the scoop. Some wire pins hold the hard foam in place while the 2-part expands.

Since it's cool in the hangar, I'll wait a day before I get into the detail carving.

This may all seem hare-brained, but what the heck. That's what experimental aviation is all about.

More forwards and backwards

The closer I get to the goal, the farther away it gets - at least, sometimes it seems that way.

My current challenge is getting the electronic timing correct, then to program in the mixture "map". To map the mixture settings with the RWS EC3 Electronic Control Unit (ECU), you will input a setting for each 1/2" step of manifold pressure; from idle, all the way to full throttle. You use the fuel/air gauge to determine what the mixture is, at that throttle setting.

This ultimately provides a look-up table for the ECU for any given throttle input.

Before I do that mapping process, I need to get the base ignition timing right. This consists of making a sole timing setting, the "base" timing. In my case, since I am using 9:1 pistons, it will be 25 degrees BTDC, with the engine at full throttle. By simply pushing a button, you use the ECU programming panel to advance or retard the timing.

So that's the theory. The reality of it all becomes more difficult, at least, for me.

First thing is the working conditions. While southern Illinois is hardly the coldest place in the nation, I am getting tired of winter.

I first tie the tail down to a front wheel of my car to keep it from going anywhere. In order to perform the timing, I have to beg a volunteer to come out and run the throttle for me.

In the above photo, (click to see it bigger) you can just see the toothed timing wheel, just aft of the propeller spinner flange. I mark some of the teeth for timing reference. Then I have to hook up a timing light and have the volunteer run it up to full throttle. I lean over the engine and hold the timing light within two inches of the spinning buzz saw. Since it's pretty bright outside I even have to shade the timing marks with my other hand so I can see the strobe flash. I actually kind of rest the side of my hand on the aft end of the spinning prop extension. I'm not sure that OSHA would approve.

I have to wear two jackets, goggles, hearing muffs and a hoodie to keep myself together. I calculated that at 35 degrees and 100 mph of prop blast, the windchill is 14 degrees. But that is really only half the fun. The other, is the sensory kick I get from the combination of the prop blast, the major engine vibration and noise, the snot blowing out of my nose fogging the goggles, and the inherent danger of working around those spinning parts.

So, after repeatedly (10 times?) doing all that, we found a few discrepancies. One, I made the sensor mounting bracket wrong and will have to re-do it. Two, for some unknown reason the engine runs worse when the timing is in the right place. Three, my digital tach bounces around so much I'm not really sure what it is telling me.

So whine, bitch and groan.

But, at least I keep working on it, and I guess that's progress.

Thanks, today, to John Eynon for patiently running the throttle for me.

Closer to the Goal

The recent effort has been directed towards getting the engine to run properly, with the RWS EC3 system. There are all sorts of variables to work through; new throttle body, injectors, homemade induction pipes, the list is long.

Right now, I'm working through getting the mixture and ignition timing properly adjusted. This is a pretty big deal and will take a while.

To complicate things, the readings from the mixture meter have been unreliable. Here is the one I'm using.

It turns out, I mounted the sensor too close to the end of the exhaust pipe. The O2 sensor is very sensitive and I guess that ambient air is getting sucked back into the exhaust pipe, between pulses, particularly at lower RPMs. This winds up showing the mixture to be too lean. As suggested, I clamped on a piece of pipe I had laying around and the mixture meter reading instantly got better.


Again, the use of this meter and sensor is only temporary, until I get everything calibrated.

Right now, I'm running the engine without the canopy installed, which is giving me a real wind-blown hairstyle. The best I have seen, at full throttle is about 2,200 RPM and 29" hg. I have old data that I had attained 2,340 RPM and 29", so I have little way to go.

I'm getting some of the wiring tidied up and pretty soon it will be time to, hook up the rudder cables, install the back-up battery and install the canopy.

On another successful note, my custom designed and built fuel flow circuit board works just great. The Dynon D180 allows you to connect a flow transducer. These transducers typically have a little fan in it, that rotates as fuel flows. A sensor picks up the pulse count and sends it to the D180 and indicates flow in gph. The problem with my system is that fuel passes through an open loop, starting at the header tank, running through pumps and filters, past the fuel injectors, and then back to the header tank. Because of this, any fuel flow transducer will sense ALL the fuel flowing and not just the fuel consumed.

Note: the flow out of the injectors is controlled by the duration of time that the injectors open. More fuel demand - the injector pulse width increases. Less demand - narrower pulse width. The number of pulses per engine revoultion is fixed.

Mike Dwyer to the rescue. Mike is a Dynon dealer and an electronics whiz. Mike designed a circuit that takes a signal from an injector. It converts an increase in pulse width to an increase in pulse frequency. It's all black magic, to me.
I got with Dennis Hannon, the avionics instructor at SIU, and an avionics student, and they fabricated and bench-tested the converter. I named the piece the Dwyer-Hannon Frequency Converter.
And what do you know? I works! Fantastic!


Mike designed in a calibration potentiometer, but the Dynon also has an adjustment multiplier. There is a little formula to dial in the calibration, so in a short while my fuel flow indicator will be correct.

Sweet!

Fowards and Backwards

Good news, bad news, good attitude.

The good news is the engine runs! Having said that, this is all extremely uncharted territory, and if it wasn't for Lynn French, I would be completely in the dark. Lynn is the character that first installed an electronic fuel injection and ignition, in his Tri-Q-200.

I used Bosch 24 lh/hr. fuel injectors, sometimes referred to as "blue tops". These are the same size that Lynn uses and it seemed like a good starting point. The ECU is programmable and you can adjust the fuel flow to your own particular application and injectors. When we first got it started, it was extremely rich. I mean rich, to the point where there was black smoke plainly coming out of the exhaust and now there are two major soot streaks running down the belly.

The first few times I ran it, it was kind of a sensory overload; all these new dials, buttons, and the like, to learn. And, it seemed like some features worked and some didn't. It was, and still is, a lot to sort out.

There is a fair amount of programming of the controller to do. The idea is to first match the basic flow of the injectors to the engine, then to map out the mixture tables.

Adjusting the mixture is interesting. First, instead of a mixture knob that you pull out, there is a mixture dial on the Programming Control Module (PCM). You use the dial for tweaking, but you use the Program Variable, Mode and Store controls to make your adjustments permanent. (Over simplification, really).

To adjust the mixture, you really can't use the conventional EGT. We welded a bung into one of the exhaust stacks and have installed a Bosch automotive oxygen sensor. This is connected to a gauge in the cockpit and it provides a digital presentation if the mixture is rich or lean. This gauge reacts much faster than a regular EGT and is easy to interpret. The first sensor I bought didn't work very well, so I bought a better one which has it's own heater.

The O2 sensor is temporary. They are designed for unleaded fuel and after a while 100LL is said to clog them up. I only need it though, for the initial mixture mapping.

All of this is so new to me and there is so much to learn. Sheesh!

After a while we (C-Rod and I), came to the conclusion that the programming button wasn't working. Now, we may be mistaken, but we think we have it right. Anyway, after lots of diagnostic e-mails, back and forth, with the controller designer/manufacturer, I pulled the unit and am returning it for evaluation.

I will say that the engine starts easily, and seems to run fairly well, considering. There are lots of unknowns here, I have an automotive racing throttle body, homemade induction system and lots of seat-of-the-pants engineering, so I am taking everything in stride.

I guess I'll work on my taxes while I wait the outcome of the controller.

My Red Letter Day

The engine started.

Yes, and I think it's starting to set in. It has been one year, two months, and 15 days since I last flew it, and the engine ran. But, who's counting?

The ice and snow is finally gone, so today C-Rod came out to help and try to fire it up. Hardly anything is safetied or tied down, I just wanted to see if the darned thing would run.


We tied it to my car, looked it all over and hit the button. The prop spun but no start. The EC3 controls both spark and fuel, so after a while I suggested that Charley spray in a little starting ether and see what that did.

I tried it again, and the engine lit and spun up! So, that must have meant the ignition part was working but there was something wrong with the fuel injector part.

We looked and looked, tore some wires fuel injector apart, checked pins, connectors, cables, wiring, all sorts of stuff. Still couldn't get the injectors to fire.


Then I said, "Let's see if maybe it's just the remaining magneto that is working and not the electronic ignition. Charley, spray some more ether and I'll try it with the mag off". It briefly roared and spun over fast as the ether fired up and tried to start.

But, I wondered if the magneto was really turned off. Maybe the mag was working and the ignition was not. "Charley, lets remove the plug wires and try it". So we pulled the Slick's wires, but the engine still tried to start on the ether.

"Charley, just for grins, pull the ALL the plug wires". So he did. To our astonishment, the engine STILL tried to fire up when boosted with the ether! Apparently, the high compression (9:1) pistons caused the either to diesel and ignite.

So, our initial supposition that the ignition must be working, was invalid. We decided to go back to the basics and make sure that the EC3 ECU was getting all the input it needed, and whattya know?

We found two wires reversed. It turns out the main power, from the "A" switch was being sent to the "B" side of the ECU, and vice-versa. Because of this the ECU, wasn't getting fed 12 volts.

I think we would have figured this out four hours earlier, if we weren't led astray by that goofy starting ether. After that was corrected it fired right up!



We ran it for about 15 minutes and seemed to be good. There is still a lot to be done, to be learned, and bugs to be ironed out, but it was a Red Letter Day!

Winter

Went to the hangar today, first time in a week. Too cold to work and enthusiasm was low. There is a ridge of solid ice, about 8" thick, all along the hangar door. If I hit the "OPEN" button, I would destroy the hangar door.

But hooray, tomorrow it's going to be in the 50s and the forecast is way above freezing for at least a week!

Maybe I can get the engine started next week. At least the oil in my new sump hasn't leaked out.