Sunday, April 5, 2015

Airplane is down for troubleshooting

Yep, it looks like N1605A is down for at least a week or two.  This past week I didn't get to do much flying due to weather and work but I did get to fly with Amy yesterday.  We flew to Friday Harbor for lunch with Harry in his rocket.  The flight was a bit bumpy coming home but since it was Amy's first flight in the airplane it was a great flight!  However, that's where the fun ends....

After Amy and I got home Travis and I took the airplane out so he could get his first ride in it.  During the flight the engine was not running like it should so we cut the flight short and went back to the airport.  After pulling the cowling we found a couple of possible causes but nothing that was obviously the culprit.  So we went to dinner with Harry and he offered to come over on Sunday (today) and do a little troubleshooting.  We started by pulling the fuel servo from his Rocket and putting it on my engine to see if we could replicate the issue.  Sure enough, at full throttle the engine started to bog down with mixture full rich.  Harry could even see black smoke coming from the exhaust pipes (mixture was too rich).  So we decided to pull the mufflers off of the engine and run it that way.  Guess what?  No black smoke and no bogging down of the engine at full throttle!  We then re-installed my fuel servo and tried it again.  Same result!  So it looks like we have found one more duck to knock off in the never ending journey to airplane nirvana!  I have an email in to the guy who built my exhaust to see what he thinks but right now it seems pretty clear that mufflers are not a good option for this airplane.

Amy at the Friday Harbor Farmers Market...I think there we at least 3 booths!
This is one of the troubleshooting steps I completed.  Here I am checking the cam to crank timing alignment.  This dial indicator is set to tell me when the valves start and stop moving.  The Dial indicator is courtesy of my brother Jim and his son Jesse.

Moving this "red cube" fuel flow transducer  from the firewall near the exhaust to this location seems to have eliminated most of my idle roughness.  Simple fix but so effective...so far anyway.

This is the bottom of that red cube where the fuel goes from the fuel servo to the flow divider.  I am getting a new fuel hose that is a bit shorter since this one is way too long now.
I took several photo's of the fuel servo replacement project today.  This is a picture of the throttle linkage washer configuration so that I would know which washers went where.

This is a similar picture but this one shows Harry's fuel servo configuration.