Fuel system makeover and engine rebuild.

Well its been a fair amount of work to get the plane back running again. I have been busy adapting the new Rotec tbi to the aircraft and doing a new fuel line system.  I have basically copied the fuel system off my other plane and fitted a one way valve and a fuel pump in parallel. Essentially it runs on gravity most of the time and the fuel pump can be used for takeoff and landing if desired and perhaps one day aerobatics.

There seems to be adequate clearance between my foot on the rudder pedals and all the components so hopefully all will be good. Obviously I still need to wire up the pump but I thankfully put all the wiring in place just in case long term I had to fit a pump. I honestly didn't think I would need to be fitting one at 1.4 hours but that's how it goes. 

I've had to make up all new controls, cable brackets and air cleaner spigots as well in the drawn out process of changing the carby over.  The new tbi also requires a primer so a 3rd cable was also required to be fitted to the aircraft. The controls were all ordered from Spruce and were here in a very short time after ordering. 

My dash looks a little like this now. Conventional throttle and mixture controls with an added 3rd cable for the primer. 

So it turns out I forgot to take photos of the brackets and spigot I had to make up to adapt this carb to the aerovee. You can see the TBI all fitted but the details of the brackets are a bit hard to see properly.   It all seems to work fine so a test flight I think won't be too far off.  I carried out a flight attitude gravity only fuel flow test after all the work was done just to be sure. Results were fine so not much to hold me back now. 

Let's hope this is the end of all the major issues and from now on it's all smooth sailing.  I'm really after that big grin after a successful flight. 

Ups and downs,round and round

Okay beware everybody, a bit of a negative post coming up again, sorry.  I have to be honest, I have been having a really hard time with this plane.

Well I eventually had a win with the Instruments. The Australian dealer came to the party and sent me a new Discovery lite. Long story. Well I assume it was new as it had the plastic wrapper on the screen and looked good. When I powered the unit up it didn't seem to have the default screen and it had extra things on it loaded like a weight and balance chart for a different aircraft. It had a few things missing like the battery voltage and amp gauges. I was not too worried as I could just load the old screens from my memory card that I saved them all to. So I go to load the screens on and guess what?! I cant't find the memory card. To say I searched high and low to find this card was an understatement. I looked everywhere. I did find some odd things searching through all my cupboards and so on as you do but no micro sd card. At a huge loss I rang the Australian dealer again who was away at the time. A few days later I got in touch with him again when he was home and he told me the card was in the old unit. Damn, I can't believe I was that silly to leave it in the EFIS. Oh well. He said he would post it no problems but I happened to ask if he could send the files via email if that was easier. "Yep, No Problem. I'll do it within the hour" So weeks later the email still hasn't come. I give up on that front as it's just too hard. It took me hours and hours to set the screens up again manually and basically I can only blame myself.  I did fly the plane again and "YES" everything works fine. I was so relieved and felt that little bit of a smile creep in. What was not good however still was the engine temps. Sky high once more but at least I could land with an ASI that was working and a fully functioning EFIS.


I had played with the mixtures again on the Aerocarb and tried to richen the baby up some more. It got to the point now where starting the engine was finicky as if I didn't have the mixture right it would flood and carry on. Still determined to get it right I flew it again. Temps still high. After scouring the forums I just decided to do what most builders do and open up the lower cowling. I cut out an extra 2 inches for a total of 6" x 13" lower outlet. I reinstalled the deflector lip and flew the plane. As per the video Below I flew the plane and the CHT's were drastically lower and all under 400f. WINNING.  The EGT's were a little high and I gave the carb a tickle richer and flew the plane again. Honestly thinking this was finally going to be my victory flight I was soon to be proven wrong. I took off and instantly noticed the mixtures were drastically wrong and I was in trouble. I felt the power loss in flight and carried out a very small low level circuit. Landed and taxied back to this.

It has spewed a massive amount of oil out the front prop hub and oil was everywhere and almost back to the tailwheel. I was soooo stoked I just wanted to give up.  Turning the motor over by the prop indicated 2 cylinders had no compression.

I pulled the motor down the next day and discovered the two rear cylinders had issues. One side had a leaking exhaust valve and the other side has a melted piston, snapped ring and a stuffed barrel.

One thing that is an absolute bonus about this engine is the price of parts and the availability. I had the heads tested and all 8 valves and seats re-ground. This cost me $125 at the local automotive machine shop. New piston rings cost me $124.50. I happened to have 2 x good condition second hand barrels from the first engine rebuild on the other Aerovee so that was good. I used one of the cylinders and pistons so I still have one good one spare in case I ever need it.  I then went and ordered a Rotec Tbi to avoid destroying another engine by running excessively lean mixtures!

I reassembled the engine yesterday and ran it for the last time on the Aerocarb. I didn't run it for long and only just long enough to make sure it was okay and running fine with no abnormal noises etc.  It ran fine and again a little smile crept in.

Today I started to carry out the Rotec Tbi conversion. I plan to get it mounted and running first just on gravity feed then decide about the boost pump. I took the old aerocarb off and set about making the brackets and so on for the cable attachments and additional primer set up. I am still dismayed by the lack of anything supplied for brackets or any forms of mounts especially for the air cleaner side. Talking to the factory regarding this was fruitless so I need to make them myself.  I really love the way the engine runs on the other plane with the Rotec Tbi so I guess I can put up with the lack of support and just forge on. I would like to add a fuel pump eventually as I noticed on the other plane the mixture control seems nicer for want of a better word to describe it. It just has a better feel. The other plane I can run gravity or the fuel pump as it has a one way valve and an alternate path for the fuel for gravity feed. It's still a pain on both as with the fuel pump on the fuel flow meter reads higher than what it is really using, I think due to the pulses from the pump. If I run gravity feed the fuel flow reads accurately but the mixture doesn't feel as linear. So we'll see when I get it running what I do long term.


Please bare in mind that this video is just my twisted thoughts on the matter. . Don't let my grumblings persuade you one way or the other in what carb or system you think is better. I'm still trying to get over the fact I'm rebuilding my engine one hour into the test flight phase. I'm actually wondering if this is some kind of record!

Instrument woes and overheating

Well I now have a total of four flights on the scoreboard and one hour on the grand total.  Achieving these milestones has been exactly that too. From the first flight I have been battling sky high temps and Instrument problems. My plan has been to try to get into the air asap after startup. Obviously though with common sense I have carried out all the pre flight checks and run ups and so on but I just haven't dawdled. I have attempted to climb out with moderate power until the temps max out then lower the nose and maintain height or do an ever so slight climb to try to keep the temps under control. Any attempt to speed up for more airflow results in a roasting motor again. On the longest flight of 35 mins or so I was maintaining about 4000 ft and temps were okay at about half throttle. Trying to get to a decent cruise setting sent them upward once more.

The MGL instruments I must say have been the biggest disappointment so far however. On the first flight my ASI was okay. On the second flight it decided to stop working. "Great" I thought, it was reading 70 kts and was stuck on that. I cycled the power to the efis thinking maybe it might just work for me again. Nope, and now it just read 0 kts,,, great.... so I chose not to panic and carried on as usual and made my base and finals approach nice and hot with plenty of wind noise over the canopy. Rounding out and touching down just fine.  I set about finding the issue with the EFIS. I have been over the wiring with a fine tooth comb. Every wire, power,earth and plug has been pulled apart and inspected and tested with my multimeter whist giving a good twist and so on to try and replicate the issue.  I had noticed that the local time had kept needing to be set so figured that the memory battery being flat could somehow contribute to this. I changed the battery and refitted the EFIS. With gentle wiggling of the wiring I had a solid reading for the ASI and thought I must have it sussed. I flew the plane again and YEP no ASI again. Getting really frustrated with this I landed. Bare in mind while I keep losing my ASI and causing stress I seriously don't need I am also battling the overheating issues to top it all off. Quite a recipe for disaster If I don't say so myself. Before this flight I had modified the Cowling inlets and Outlets as Per instructions from Sonex. I had also done the mod to the heads in regard to opening up all the airways around the exhaust ports and in between the 2 cyls on the heads like perhaps others have seen pics of  before.

All these passages have now been opened right up for added airflow. I wish I had taken some photo's of them opened up but I can do that next time I am at the airport.

These pics are a bit of a before and after in regard to the cowling Lip added. It is basically 2" long over the original 1" long and has the tapered sides as well.  On the last flight I did I saw 390 f on three cylinders and the one cylinder still skyrocketing up and over 450 f.  I seriously think I have run over a black cat that was pregnant with thirteen black kittens. The mods certainly have reduced three of the CHT's , I just wish all four had been okay.  I have also been playing around with the baffle seals a little and replaced a section that was in three pieces with a singular piece in the hope the air has not been bypassing the joins. I have also spent some time just trying to work out why 1 x CHT would  be so much different. The sensors all read the same when turned off and warming up. It's just when I get airborne one heats right up.

I am hesitant to modify anything now while I have no Instrument and flying obviously is not going to happen so I now just need to sit on my hands and wait.

I rang the Australian Dealer for MGL and asked how he was progressing with the checking of the ASI and EFIS in general.  It seems highly likely now that it will be heading off to South Africa for a proper test. I honestly wonder what next. I am thankful it is still in Warranty having only bought the whole system around 10 months ago. Let's see what comes of the testing and progress from there. I mostly bought a MGL system as my original one in the Aeropup has performed flawlessly from day one. I fully expected the second system to be the same in terms of reliability but perhaps I was just unlucky.

Well sorry everyone for such a negative update. If I can get on top of these two issues I think it will then be smooth sailing. I am just a little frustrated that's all due to the fact that I have to fly forty hours in one calendar year to finish the test hours off or I have to go through the whole registration process again including all registration and inspections costs so the clock is ticking. Secondly winter is fast approaching and right now almost to the day the best weather for the flying season is upon me. Calm winds, blue skies and no big thermals inland. With the EFIS heading to South Africa most likely I will be grounded for a Month at best guess. Time to twiddle some thumbs.

The culprit

Back in biz it seems after a short delay.

I managed to change the coil out and back in business I was. It's hard to imagine a part failing so early in the programme and I was a little worried I had misdiagnosed or made an error somewhere. It turns out I worried over nothing and it's all good now. The coil had a few slightly different markings but was identical in all major aspects so I bolted it on and gave it a whirl. The engine fired up and ran great on both ignitions. Happy days once more. Now to just sort out this overheating issue.

This was the little bad boy here. I should just throw it straight in the bin but I think I want too look at it for a little bit longer in disgust, then chuck it away.

First flight video

Unedited video from the first flight. We had a proper video camera on the day and completely forgot to use it in all the excitement.  Mobile phone video was all we managed to obtain.

First flight

Well I can officially say I have flown the plane !!!!!

It didn't go quite according to plan but nonetheless it was a good outcome. I have to say I was very nervous before the event. I ended up with quite a crowd which was not ideal but expected.

I did have on hand one man on the ground who was my emergency situation guy. He had the car airside, handheld radio and a few different fire extinguishers just in case the worst happened. I just felt better knowing he was ready and close by. Not that either of us thought anything would happen, still we just wanted to play it as safe as we could.

After a good clean of the windscreen (as you would be amazed how much dust can accumulate) I was taxiing for runway 21. There was lots of talk of this and that and people giving advice which I respectfully didn't want to hear as I had my plan in my head of the flight and that's what was going to happen and did happen, to a degree.

I had an issue with the ASI at one stage and I hadn't seen a reading on the dash in this regard during the taxi out and line up. I made the decision and taxied back to double check it. As luck would have it it was fine but I felt better checking.

 I strapped in again and set off once more for runway 21. Another aircraft was in the circuit, as it happens a good friend so he extended downwind and I lined up. Radio call made, accelerated and it just seemed to leap off the ground like a jack rabbit. I climbed out watching airspeed, climb rate and the CHT's passing into the yellow. I was at about 33" manifold setting and climbing out at 85-90 kts in  a very shallow climb to increase airflow. I then saw the gauge hit the red and leveled out for a 500 ft circuit. Throttled back on a short crosswind and turned downwind on a very low power setting. I was throttled right back and seeing 95-100 kts. The gauge began then finally to drop somewhat and turning base called and final right after for a very bunched up circuit. I was very high at 500ft for the markers so landed about 1/3 of the 2km runway down. Touchdown was perhaps not ideal as it felt like the tailwheel definitely touched first then the mains. It was a event free landing so taxied back to the hangar for a total of 6 mins flight.  That also was my first ever flight in a Sonex.

I had known almost from about 100-200 ft I had the engine set too lean. It heated up way too fast and I knew I was going to have to get back quick. I had heard all the reasons why builders shouldn't test fly their own planes and so on as if there is a problem that they will try and save the plane and not themselves, well I don't think that is the case with me. I don't think I am that attached to it. From all the flying I had done in the other Aerovee I knew the temps and so on and flew accordingly and not dangerously I feel. I have always practiced low level circuits so there was a good reason to do one with this Sonex.

Back on the ground and a while later I took the cowl offs and richened up the Aerocarb. I was quite ashamed of myself by how much I had actually had to richen it. I think the next flight will be ok now the engine is getting a heap more fuel. It made a big difference on the last plane so am sure it will make a big difference on this one too.

I was about to go fly the plane again and when I carried out a Mag check found I was running on 2 cylinders only on the primary ignition. Figuring I had melted some ign leads or something I took the cowls off again and everything looked ok. I had found which cylinders weren't firing as the EGT's dropped significantly on number 3-4. Well actually number 1 and 2 but I am a little bad and number my cylinders on the efis the opposite way as it just seems to make sense to me. Anyway the lower coil wasn't firing. I took the cut off wire off and tried again. No change. I took the plugs out and changed them. No change. I checked the coil with a multi meter and compared it to the top coil but it seemed the same. I checked to make sure the coil had the additional earth and that it was ok. No change.  I closed the hangar doors and gave up.

Somewhat very despondent I looked up the Sonex site and thought about how long now I was going to be grounded waiting for parts from the US and the cost. I looked up the builders website and saw the number for the replacement coils from a local mower shop. I cross referenced the numbers here in OZ and my brother ordered me one via his work that specializes in this industry.  The coil as it turns out arrived today in the post. It looks the same as the original from memory and I will change it out tomorrow and see if the engine runs again on the primary ign.  It was about 1/3 price total delivered if I take into account the foreign exchange and freight. I like to support Sonex but can't justify the time and cost on this one. A failed coil after 6 mins flight is infuriating. I am not blaming Sonex as it is in no way their fault but still frustrating to have a failure of such a new part.

The weather is looking great for flying on the weekend so if all goes well I will be reporting some fine flights very soon. I also want to change the needle to a number 3 from a number 2 in the Aerocarb so that may happen this weekend too.

Oh I almost forgot to tell you how it flies :)

 Well..........

  Downwind was about the only time I got to semi relax. It seems quite touchy in the pitch and the roll is quite responsive too. It has the extended ailerons so putting it down to that. I had to hold a bit of right aileron to keep it level so will need to add a trim tab of sorts. I didn't have enough time to really get a feel for the vision over the screen but it seems a good forward visibility is attained in cruise. I was all over the place in regard to height and I did try somewhat woefully to try and trim it out with the dial a trim. The trim worked fine but I just didn't have time to look at the dash and fly and set up for landing so that's a job for another day.  I am happy by the way it flew and think it will be a really nice plane once I get some time on the Hobbs.

CofA

Well I have now finally received my CofA.

 It was a great feeling to have that hurdle ticked off. The day went ok and mostly it was sorting out log books, maintenance release paperwork and all the little things required for CASA and the SAAA. The inspectors had a good look over the plane with a keen eye and were happy with what they saw. I had some help from a local club member and fellow builder during the day which helped beyond all measure.

The guys flew up from Perth in the RV7 for the day. 

The Inspectors and myself for the happy snap just b4 departing back for home in the RV7.