So while I was looking up the part number for a replacement diaphragm spring, I noticed that they looked nothing like what I had in my carb (I.E. they were shorter).
I called a local outdoor equipment dealer and asked about a Walbro diaphragm spring and they said they had it. I told them it was for an HDA carb and the guy just said "yeah..."
I took my carb with me when I went to pick it up and spent a whopping $0.60 on it. The pic below is the spring that is my carb originally after the slight stretch on top, the new spring, and a spring from a WB that I was curious how it compared (it's a smaller diameter spring). After seeing this, I began to wonder if my spring was defective (it happens) so I rebuilt the carb with the new one. I also took off the velocity stack from the motor and put in one of the FlowMasters from EF. The water bottle I was using was too long to make the connection from the front of the tank to carb a pain to remove.
So I took my Edge with the new set up out to the field today. I found that if I choked the motor it would start but wouldn't transition to anything past 1/3 stick and then quit (I.E. too lean). So keeping
@Terryscustom guide to tuning in mind, I kept richening the low until it transitioned. I finally got it to the point where it would transition but the idle was a little rough so I killed the motor and richened the low a little bit more. When I restarted the idle was better and it still had a nice transition so now it was time to test it out. I took off and flew around with 0 problems. I first tested inverted downlines and no hesitation or bogging so then I tried knife edge and then rolling harriers (all high up) with no problems. The only problem was the throttle curve was different. I had a linear curve before with the velocity stack so I landed, adjusted and went back up.
After landing, I shut down the motor and checked the temp. It was around 180F. Just to double check my low, I richened it 1/8 of a turn. Next flight, again no problems until I was harriering around for a while and then went high and came down at idle. I started to pull up to check the transition and it started to go but then died. I was high up so I landed OK. Checked the cylinder temp and it was around 160F. So my guess is that the engine loaded up and then the idle was a little too low from the rich condition and died. Took out the 1/8 of a turn on the low and went back up. I flew around for over 12 minutes at a high altitude constantly testing. Transition in straight and level was perfect and then I tried going from idle to full power on both 45 and straight uplines. Transition was still good and maybe a very slight on the straight uplines which was to be expected. At the end of the flight, I put it in a hover and punched it. Engine revved up and no problems pulling out.
Cylinder temp was back to around 180F at the end of the 3rd flight. So it seems I finally have this thing running right.
