Dave Gallagher Zenith 601XL
Dave Gallagher: Zenith 601XL, Cincinnati, Ohio
My name is Dave Gallagher and I have a Zenith 601XL flying with a Jabiru 3300 engine. I started to build in September of 2006 and rapidly progressed through the various kit sections. At Oshkosh 2007, I approached Pete Krotje at the Jabiru USA booth and ordered an engine along with their firewall forward kit. In November, I received a call from the local Conway trucking terminal that my two crates had arrived. At about that same time, I was notified of a FWF seminar that would be held at the Jabiru USA facility in Shelbyville, TN., later that month. Talk about excellent timing!
The 2-day FWF seminar was a great experience and I highly recommend it to anyone also getting ready to install their Jabiru engine. Interestingly enough, Jon Croke of Homebuilthelp.com was there to film the workshop so I ended up being in the DVD that he sells. If you cannot make the seminar in person, the DVD is certainly a close second.
My engine installation was very straight forward and the FWF parts went on pretty much as advertised. The only thing I had to play with was the dual throttle installation. With a long, thin torque tube going across between the two push-pull throttles, it is very important to get all the friction you can out of the system.
In July of 2008 I received my certification and on July 24, I made my first flight. During my entire flight test period, I did not have any significant engine issues to address. As expected, I had to make a few carb jet changes to get the right combination. Even though I did my initial break-in and flight testing in the summer, I never saw CHT’s that were too hot that I ever had to discontinue a test point due to them. This included several climbs from take-off right up to 10,000’. The CHT’s were a bit warm, more so during the break-in period, so I did tweak the ram air ducts some to attain lower cylinder temperatures. Initial oil temperatures were OK, if not a bit on the warm side also, so I sealed around the oil cooler and probably gained around 5 degrees. The item I played with the most was the addition of a flow divider in the air inlet to the carb. It really helped smooth out the air flow, narrowed the spread of the EGT’s from cylinder to cylinder and added a noticeable amount of power to full-throttle climbs.
Prototype flow divider installed in elbow upstream of the carb inlet
The following is an extract from my Dynon engine monitor during my flight to Oshkosh 2011: Under a cloud deck that kept me in blistering 93F heat at 2000’ MSL, my economy cruise RPM of 2700 resulted in at oil temp of 225F, CHT ave. of 293F and EGT ave. of 1349F. When I was able to later climb up to 4500’ MSL and lower my cabin temps to 78F at 2650 RPM I saw an oil temp of 210F, CHT ave. of 279F and EGT ave. of 1282F. I am strictly an economy flyer as you can tell by the RPM’s I run above so my average cruise speed when by myself is around 110-115 MPH. When both seats are filled, this goes down to about 105 MPH. The fuel burn at these speeds is between 4.5 to 5.0 GPH on a consistent basis. My rate of climb by myself can easily hit 1500 FPM but I am usually not trying to set any time to climb records while flying. With two people at max gross, I can easily get an honest 1000+ FPM when I want to. I have never formally measured my take-off distance, but I imagine I am getting off in around 500-600 feet, certainly sooner than any C-152 I have ever flown . My empty weight, after the 601XL wing mods is 789 pounds.
My Jabiru powered Zenith 601XL flying over the USAF Museum in Dayton, OH
I now have just over 200 hours on my Zenith 601XL/Jabiru engine combination. Oil consumption with 15W50 oil is very low. As recommended by Jabiru, maintain your oil level on the low end of the dip stick marking for best performance. Other than regular oil changes and replacing the spark plugs at 100 hours to install the iridium plugs, I have not had any undue maintenance issues. I did just notice one of the muffler retaining springs was broken during my last oil change and ordered a replacement. I also plan to change the ignition components, as recommended at 200 hours, during my upcoming condition inspection.
