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Hi,
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.
Thanks,
Darrell
Tags:
I do not turn electric pump off until engine running.
We replaced the lead battery by a high power LiFePo battery that work very fine.
Hello all,
I have a zenith 601 with a Jabiru 3300. (new in 2006). I worked all day trying to get it to start. It was about 38 degrees when i started trying and didn’t get much warmer all day. Not one catch. I kept recharging the battery and trying again. I pulled the choke out (literally pulled on the knob while cranking) and I had the throttle off. Nothing.
I did discover something that certainly looks wrong. The P-lead connector on both coils (the fact that it’s both of them give me most doubt) are shorted to ground. Did BOTH of my coils go bad at the exact same time? To explain, I an take the p-lead wire off and there is continuity between the p-lead pin on the coil and the frame of the plane (see pic for what I a calling the p-lead). Is this normal? Do the coils short to ground until the engine reaches a certain RPM?
Hi Ernist
Those wires should only be shorted to earth with the ignition OFF. Check the Jabiru installation manual for details. I notice your starter motor earth lead is corroded. That may also need a repair.
Looking at that picture I would remove the corrosion on and between the ignition module and magnets on the flywheel, then check the gap.
Back in 2008, Jabiru issued Service Bulletin JSL 005-1. This calls for the starter motor grounding cable to be attached directly to the starter - it appears this has not been done on your engine. I would either clean up the corroded cable or get a new one and attach it directly to the starter per the service bulletin.
The Jab has a permanent magnet alternator and depends on a vigorous spin of the prop to fire the engine. I've heard of a lot of complaints about difficult starting in cold weather, but I followed the service bulletin and replaced my battery with an EarthX battery and have never had a problem - ever! The EarthX is a lithium battery and has almost no internal resistance, plus it has a higher resting voltage. It spins the prop so fast it has to start!
But if you indeed have a healthy battery that spins the engine well, first follow the service bulletin!
John
N750A
I cleaned up the corrosion, re-gapped my coils, and most importantly, I re-routed my starter ground to the back of the starter per Jabiru directive below. Starts perfectly!! I encourage all researching this problem to try the starter ground re-route before spending a lot of money on alternative ignitions. Time will tell, but I think my cold-starting issues may be greatly lessoned now.
https://jabiru.net.au/wp-content/uploads/2018/05/Starter-Motor-eart...
Glad it worked for you, Ernest! BTW, off-topic, but it appears from the picture your air-oil separator is clamped with a stainless band clamp directly attached to an engine mount tube. Unless it's there and I just can't see it, I think that tubing should be padded with a wrap or two of silicone "rescue tape" to protect it from erosion should the stainless clamp vibrate and eat into the chrome moly tubing, or, rig up a mount utilizing a padded Adel clamp on the tubing.
John
Thank you John! I will take care of that the next time I'm at the airport. I have only had the plane a few months and am trying to find and fix all the potential problems.
Ernest, that is great news! I'm glad that this problem is fixed. You did a good job cleaning up the corrosion, and it really shows when looking at the "before" and "after" pictures.
Merry Christmas, and Happy New Year!
Darrell
Hi Ernest,
I'm no expert on these engines. You can tell from my first post that I'm new to it. In 4 days I'll celebrate having this plane for 1 year, and I'm always grateful for the help I've received in this forum.
I understand engines, and have always understood that when an engine won't start, it's generally one area out of three....air, fuel, or ignition. I think we can rule out air as your problem.
For the other two, only work on one at a time. My problem turned out to be the carburator (fuel) and my lack of understanding of it. With the advice I got on here, I was able to operate the Bing carb correctly, and my starting issues were solved.
Seeing the corrosion on your engine, I would focus on the ignition. You checked the P-lead and said they're shorted to ground. Turn your ignition switch on, first to both, and check the P-lead to ground on each lead. Then check each (left on switch, right on switch) separately. They shouldn't show a connection to ground.
Pull at least one spark plug and inspect. Is it wet? If so, is it fuel, or wet from condensation?
Is there corrosion on the flywheel magnets? Ignition module?
You didn't state how well the engine turns over. Some have recommended a battery. They gave me the same recommendation, but my engine turned over really good with a new Odyssey battery. I just ran it down trying to start the engine.
Have you checked the distributors? I'm not sure, but I think you've had a lot of rain recently, and moisture could have gotten in the distributor. A hair dryer would be helpful there.
Finally, do you have the 3300 Operation and Maintenance Manual? If not, you can download it from flylightning.net
For what it's worth, I always used a strip of brass shim stock with 0.010" thick between the coil and magnet as this is the MINIMUM clearance as per Jabiru. Clean all corrosion off both magnet and coil to get the true clearance 1st.
Loosen coil and pull away from flywheel, then temporarily snug them to hold coil up till you rotate the magnet back under coil. Insert brass shim stock, let the coil back down on the brass covered magnet, tighten coil bolts, rotate flywheel by hand while pulling on shim stock to remove. Turn through several rotations to "feel" for any contact, look for any rubbing.. Yer done!
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