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Poor cranking - my problem resolved.


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Since the onset of winter, my Jabiru 2200 powered Cheetah has been unwilling to start on the battery alone. Fair enough I thought - many Jabirus exhibit this behaviour.


Some people solve it by using external warmth before starting. I've been solving it by using a jump-pack. Lately it hasn't even been starting on its own battery (Odyssey) after warming up.


This morning, it wouldn't start at all. With the jump-pack, it turned over pretty well, but not a single fire.


Checked the spark - as weak as the Liberal party.


Disconnected the battery and tried just the jump-pack in case the battery was stuffed. It barely turned over.


Wondered about starter earth as discussed in Jab forum at Narromine. Tried earthing the starter with a jumper lead. No better.


Measured voltage and resistance here and there, found the starter solenoid wasn't right. Not enough voltage getting through, and too much resistance between HT posts when activated. Tried connecting jump-pack directly to the positive on the starter side of the solenoid and the negative to block at starter. Starter turned the engine over really well, but the earth wire between solenoid and battery melted.


This seemed to prove that the solenoid had been leaking to earth, to the point where 2 batteries were required to turn the starter, and eventually there wasn't enough spark left to power the ignition as it deteriorated.


Went into town to get another solenoid. Only Super Cheap was open, however they had the identical solenoid. What does that tell you about the one Jabiru supply?


I bought it as a short term fix, fitted it and a new earth wire.


It still didn't start off the battery, but I figure it was flat by now.


Used the jump-pack and it fired straight up.


Went for a short 2 hour jaunt. Charging system seemed fine. Got back and shut down, then started it off the battery a few times. No problem.


The acid test will be the next cold morning, but I'm betting it will be good.


So, if you are having trouble starting your Jab, I highly recommend a closer look at your solenoid. This was the standard one supplied by Jabiru, and you can find them at Super Cheap (SupaCheep?). 'Nuff said?


I figure a good test is to disconnect your battery and bridge it straight to the starter and the earth at its base. Probably best to disconnect your solenoid first, in case it leaks to earth like mine did. If the battery turns the starter a lot better this way, the solenoid isn't doing its job right.


Note: I'm not a LAME, so run it by one first. I had a LAME helping me diagnose, so it wasn't all cowboys and pot shots.


Cheers, and let's be careful out there.





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Wow - spare parts at Supa Cheap :thumb_up: - spark plugs, leads, caps, oil filters, and solenoids. (What else?) Not that many years ago people joked that you could just about buy Holden parts at the local deli (or just grab a bit of fence wire from the side of the road and repair what ever was broken). These days of course the Holden car is quite a sophisticated vehicle. 040_nerd.gif.a6a4f823734c8b20ed33654968aaa347.gif


I guess what I'm trying to say Slarti is I don't see being able to buy parts at Supa Cheap as a reflection of Jabiru qualtiy - I bet any Rotax, Continental and Lycoming driver would love to have spart parts available at automotive prices in so many locations across the country. If ya get my drift. 011_clap.gif.c796ec930025ef6b94efb6b089d30b16.gif


I would also think that an auto solenoid would be quite a robust unit, given its intended workload.


Just my 2 bobs worth.







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I hear what you're saying Pete. You can get some great stuff at great prices there.


But this solenoid was generic, looks cheap and light, and was cheap. It definitely failed progressively, and it was only 6 months old.


Given the symptoms match the problem a lot of people have with Jab motors, I just thought I'd share my findings in case it helped others. I didn't set out to vilify Jabiru for using cheap components. That's how a company keeps costs down.


This was not a robust unit. I will be buying one of those.



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Guest brentc

20 thou plug gaps,


10 though magnet gaps,


clean distributor caps,


15w50 oil,


manual crank by hand on propellor first,


fuel pump on first,


works for me!


PS: Oil Cooler from Repco, Toyota Camry starter & Falcon lifters (in the old model engine)



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Guest brentc

Nelson, your engine starts every time no matter the temp because of your carpet lined centrally heated hangar with built in love nest, so you don't have to worry. I wish we all that that luxury.


Oh crap, I just realised I missed my 1,000th post. I was going to have a party.



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Who's counting?


Run that by me again. What has a faulty solenoid got to do with the choke adjustment, spark plug gaps, magnet gap, choice of oil, craking and fuel pumping ?


Slarti carefully explains the fault was down to the solenoid shorting to ground on activation.


An interesting and unusual problem that would defy the logical process of fault finding ! Yes it was broken, and he fixed it. Any Jabiru engine owner with engine starting problems might really benefit by checking the solenoid, which was the reason for writing the post.


So what was the point of the subsequent posts ?


Jack. 071_yawn.gif.43c7f5f86675fec124ffe33bd2e896f0.gif071_yawn.gif.ed9fe9d0060bea1ba30edf7c498c2aed.gif



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Guest brentc
So what was the point of the subsequent posts ?

Because we all like to discuss and theorise. It's just what we do.


Whilst the solenoid may have been the problem on this occasion, the other points I posted are also important to cold starting - you can't have one without the other so all valid in my opinion.


My thoughts are that this problem may not be relevant for Jabirus because the engine is fitted into a different aircraft type and different wires and or fittings may have been used in the build. Hence my post.



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  • 2 weeks later...

I figured this thread was SO appropriate because I have been having increasing trouble with cranking my J230 (approx 60 hours old). I did lots of trouble shooting and the idea that the Solenoid may have been at fault was attractive. I replace the solenoid and guess what!! No change. Everything pointed to the starter motor and this proved to be right. I fitted another one today under warantee and all is well. The starter is the last place I would have looked!!



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Because we all like to discuss and theorise. It's just what we do.

And they were trying to help .... Jack.


I didn't hear Ross complaining that he receieved too many suggestions of where to have a look.



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Cold starting


Last winter and so far this winter two of the jabs here have been using HOT water poured through a funnel and hose onto the carbie, eureka!! Seems that when the temp is down to below 8-10 deg this method is required. We have no power at the hanger, so use either gas kettle or thermos. I have thought about heating the wheat bag used for injuries on the micro wave before leaving home and positioning in around the carbie to see how this would go, perhaps someone could try this.


Changed to thinner oil last week at 100 hourly, may make some difference to the temps mentioned above.







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I think you will find that the main cause of bad starting for Jab engines is Qdyssey batteries. Contrary to their advertising they do not have good cold starting ability. You have to turnover the engine at about 300rpm to get a spark of enough intensity to start,


If you remove the steel case that contains the battery body, you will find a great improvement, the battery proper is held in the case with silicon.


It is possible to fit a Kettering system to provide a battery powered retarded spark to get you going. The kettering system gives a full spark at low rpm, but it involves a bit of fitting.


I have this problem and have found the best system is to prime, using choke and pull through a few props, then use a jumper to aid the battery.



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Actually I noted in the last magazines, wasnt sure if it was pacific flyer or the RAA one, that there is a lithium ion battery now specifically for Aircraft. I noted that the article went to great pains to point out that the chemical composition wasnt the same as the higher energy density, but perhaps more dangerous LiIon batteries used in mobile phones and laptops.....


Anyway the purpose of this email was to see if there is anyone who has tried one of these new tech (from an Aviation perspective) batteries.


the downside that I can see (and it may not exist) is that most LiIon batteries that I have used have a lowest voltage you should discharge to. Usage beyond that voltage leads to damage. If that is also true of this checmical composition then we will need to add circuitry to prevent discharge beyond flat. The upside (and maybe downside!) is that the change in upfront battery weight is going to have plenty of impact on CofG that may be good or bad depending on your particular install, but wont be harmed by the added weight of the additonal circuitry.







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Wally at Narrandera was telling me that about a 5 minute stint with a hair dryer sitting on the inside edge of the lower cowl outlet will let his J230c start with just a touch of the starter button on these cold mornings lately. It would soon heat the whole outside of the engine and get the chill off the oil after a few minutes.



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I think you will find that the main cause of bad starting for Jab engines is Qdyssey batteries.

Now you tell me Ian. 036_faint.gif.544c913aae3989c0f13fd9d3b82e4e2c.gif


I didn't mention that while replacing the solenoid fixed the big problem (wouldn't start at all), it hasn't fixed the cold starting problem (and yes - I do all the usual stuff mentioned earlier). I have another test to do this weekend that will prove whether it is the battery just being rubbish when cold or not.


Ross, the LSA55 Jab I used to hire a lot is also treated to a thorough warming before attempting a cold start. It was -7 when I was leaving to go to the Camden Haven flyin last year. I put the paint stripper gun in the cowl as usual, and while my attention was elsewhere, the gun slipped and moved against the cowl. By the time I noticed, it had bubbled the fibreglass pretty badly. I nearly didn't go at all. It has since been replaced at my expense. So pre-warming has its down side.


Assuming the battery just doesn't have enough cold cranking amps, does anyone use a good motorcycle (or otherwise) battery which does start a Jabiru on -7 degree C mornings question.gif.c2f6860684cbd9834a97934921df4bcb.gif


Recommendations please.



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Lithium Iron Phosphate (LiFePO4)


The battery mentioned in the magazine article was a Lithium Iron Phosphate battery (LiFePO4 chemical symbols).


The word Ion refers to an electrically charged atom, radical or molecule not necessarily an Iron molecule or atom for which the chemical symbol is Fe (short for the Latin word for Iron)


The following points in italic text are adapted from the article "Lithium Iron Phosphate (LiFePO4) Batteries for Aviation Applications" in the July issue of the Pacific Flyer pp.10-12.


The Lithium Iron Phosphate battery was a safer battery than the Lithium Ion battery and was classed as "Not Restricted" and meet the requirements of IATA Special Provision A45.




Safer than earlier Lithium Ion batteries and even safer than lead acid batteries.


Light weight, half the weight of equivalent lead acid battery.


Extremely long life up to 20 years typically in excess of 2,000 cycles have actually Passed 7,000 cycles under test.


Battery can be used for high power applications as well as stand-by power.


A 12V 20AHour LiFePO4 battery weighing 4 Kg is all that is required for engine sizes up to 3,000 cc.




No explosive Hydrogen or other gas produced under charge so will not catch fire or explode with overcharge.


Extremely low self discharge rate compared to lead acid battery.


Can be operated in any orientation including inverted.




There were a few more very useful benefits mentioned in the article including discharge and voltage characteristics plus a website URL not repeated here.






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Good point. They aren't cheap either.


The article only has an email address [email protected]


Their website is here.


I found a better looking Oz supplier website here. They are for electric bikes, but seem to give an indication of price. A 12.8v 20aH LiFePo4 weighing 2.8Kg and measuring 185 x 170 x 75 is $453.



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Guest Bendorn

Hey Ross,


I was flying in Swan Hill on Monday and Cliff Banks was talking about Jabbies and cold morning starts and how to rectify it with a 10c washer. (I'm sure there's a bit more to it then that.)


I cannot recall what was done but give him a bell at Suncentre on 0429 346 650 and get the low down. :thumb_up:





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