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!
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