I've had this 601xlb with 3300 engine with Bing carb for 2 weeks now. This plane and engine are new territory for me. It ran great with no problems for the ferry flight from Michigan to Kentucky, Due to weather, I've now only been able to get it out twice, and both times I had the same issue.

I followed the checklist, and the engine cranks, but fails to start. I eventually ran the battery down, both times. I charged the battery, which took about 20-25 minutes. Then, I just hit the key, and the engine started immediately. Subsequent starts were immediate, too.

It runs great, and this is the only issue I've had with the engine. Could it be that I'm not priming with the electric fuel pump enough? The checklist calls for 4-5 seconds of prime, then pump off. I don't think I'm flooding it. I'm not familiar with this carb, though, so I don't know.

Any advice would be greatly appreciated.



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Jabiru, being from Australia, doesn't like the cold. There is a mod to open the starting jet in the float bowl to allow for a richer mixture during starting. Also, battery has to provide good cranking speed for the magnetos to work. The fuel pump won't overprime. Just makes sure the float bowl is full. When the electric pump builds up pressure, that's enough. Throttle closed, start cranking, engage choke, if engine starts ease off the choke. My method, others my use different method. I have electric heat on the sump. Again, battery has to be good. No need to run it down. If battery starts to degrade, stop. It's not going to start. 

Thanks Jay! Your answer explains to me why the engine started right up when we got the plane. There's an engine sump heater, like yours, and the previous owner had the heater plugged in for a couple of hours before we arrived. I'll have to start plugging it in for a while before I get the plane out.

I have a new Odyssey battery, and keep it charged. I just ran it down from the repeated attempts at starting. I stopped when the cranking became sluggish, not wanting to completely discharge the battery.

Unless the engine is warm, I always pull the throttle closed when starting, winter or summer. A closed throttle is necessary for proper functioning of the choke port that channels air flow at cranking speed to draw fuel through the choke jet into the engine. The choke on a Bing is like a mini carburetor such that if the throttle is open slightly, airflow will bypass the choke port through the main venturi and eliminate the choke's function.

During warmer temperatures a closed throttle is still needed to draw fuel through the idle jet. Hopefully, the quick starting will continue for you with a strong battery.

Thanks, Don, for teaching me more about this engine and carb. I will be able to plug in the sump heater while in my hangar, but was concerned about what to do when away from home. I'll give your method a try next time I'm at the airport. The learning never stops!


Since you are a new Jabiru owner, you should go out to the Jabiru.net.au web site and read through the support tab for Service Bulletins, manuals and such.  Here is a cold start article that covers some of the comments already listed here and more.


Welcome to the club and good luck,

Dave G


Thanks for the direction to the Jabiru.net website. I will begin studying the information they provide. I saw that Arion Aircraft is a Jabiru dealer in Shelbyville, Tn, and that's 92 miles SE of me. Hopefully I can fly down there when I get more familiar with this plane. "Any excuse to go flying!"

Thanks, again


As Jay mentioned, this engine needs a good cranking speed for the magnetos to produce a healthy spark.  One comment that I have seen many times is that (if you don't already have one) switching to an EarthX lithium battery markedly improves starting, especially in cold weather.  Lithium batteries have a higher resting voltage and almost no internal resistance, so they spin the engine much faster and that helps the mags produce a strong spark.  I've used an EarthX for years - I'm in East Tennessee, so the winters and temps are relatively mild here, but even on those rare, sub-freezing days, I've never seen the engine fail to start!



I was watching one of my videos recently and realized the first 10 seconds show a "typical" cold engine start of my 3300 with the EarthX battery. Full disclosure:  obviously it was a beautiful day and the OAT was likely 40+F and my 3300 has a Sonex/Aeroconversion "AeroInjector" throttle body carb and not a Bing, but the point is the EarthX spins the prop so fast it almost guarantees instantaneous starting!  :>)

I have a 4th gen Jabiru 3300 in my 750 Cruzer.  I also found that it started MUCH better with the EarthX battery.  I initially switched from the Odyssey to save weight, but the improved starting is a real bonus.  

I am a new 601 with  3300 owner also and had the same problem. Jabiru Pacific LLC has an article on cold starts that has worked for me. Mags and master off! Pull the throttle and choke completely out, turn the prop 6 times, then start. I hold the choke out during starting. Works everytime


The weather was finally nice yesterday, and I was able to schedule time with the CFI. I plugged in the sump heater for about 2 hours, and I'm happy to report that the engine fired right up, and ran great.

Unfortunately, I had to abort the takeoff, because the canopy latch popped loose on my side, but that's a discussion for another thread. Today, I'm going to the airport to investigate that, and I think I'll pull the plane out and try a cold start, using the techniques presented on here. 

Thanks to everyone for the help.


Good news again! It was 38 degrees F when I got to the airport this morning, so I decided that the first thing I was going to do was attempt a cold start. I followed the advice I got on this thread, and was so happy to have the engine running after about 3 seconds of cranking. Thank you to everyone!


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