good idea

BJ64- Yes that's EXACTLY what it does as you mention. It too started by getting a little further along in the start cycle, but decreased to just the propane now.
I will continue to isolate now.

I've have not changed anything prior to this problem, but who knows?

fw190- will try disconnection the plug immediately and see what happens-will have to think about how to do it fast.

will break out the blower if the other ideas are failing.

I will be out starting it in the morning so will let you all know how it's going-we'll get it solved

thanks

Jack

Vortex

I was out for a few flights last night with my JJ1400 in the Boomerang, and on the first start attempt it failed which is unusual as it very rarely does apart from cold gas etc. But the funny thing was the display showed your 64200 well more a flicker between 64200 -64600 it never showed a start bad message or made any attempt to spin the turbine again.

I switched off and tried again, I heard the glow plug tone then again the rpm figure flickered around 64K.

I did have the turbine out as I have been playing around with pre load.
I have my Glow Plug wires down one side and the RPM/EGT down the other, and I have about 6 flights since I took out the wren so know it was ok before. Glow plug wires are twisted or twitched as the call it in Aus (sorry BJ could'nt resist).
But I may have had the wires closer together this time, I did also have the glow plug wires cable tied to one leg of the starter housing.

So I snipped of the cable tie and pushed the wires back as far as I could to the sides, tried again then got a series of glow bad messages so after replacing the plug I decided to top up my ECU battery as I have suspected this battery in the past as getting a bit iffy if was charged the day before flying, needs to be charge before each flight.
I am using a jetcat 6 cell 1200mah Nicad in the Boomerang, and used a 2 cell lipo 1000mah in the bobcat which I charged every flight.

It then fired up as normal once I topped up the battery and replaced plug, moved wires etc.

The reason I am mentioning all this is, I got the same message as you, but not sure why but this is what I did and it went away.

Separated the glow wires as far as possible to the RPM wires
Fully charged my Battery,
Replaced the glow plug, (as the glow bad messages made me suspicious)
Un plugged/plugged in and out my Rpm cable (I have it on an extension) as it had been disconnected when I removed turbine.

I would try the above with one extra, try another battery. When I first got my turbine and new nothing I had endless problems getting it to start, when I went to a friend who new more about turbines, he fitted a different battery to save waiting on mine to charge and our problems were solved.

Fit a new plug, and make sure the contact is also very good, especially if using the booted connector, I once had a series of glow bad messages caused by the spring in the connector sticking.

LoL @ the "twitching" Xair..

On the subject of the booted glow wire lead - just in case you don't know Vortex, take extra care when clipping the glowplug wire down onto the plug it you're using the standard JetJoe glowplug boot. It is extremely easy to push the whole silicone boot down too far and end up shorting the hot lead down on the plug base without even realising it. And if that happens, you can toast your FADEC (blow one of the controllers MOSFET's).

In fact, I was so worried about accidentally doing this, that I carefully pulled the boot back off the plug. Once I'd done that, I got a better appreciation of how the whole thing works. It's a pretty simple system, and when all goes well, the 'clip' pulls back just far enough to clear the diameter of the positive pole of the glowplug and then locks into one of the two small grooves cut into the pole. There's not a lot of room for error in this design, and it's really easy to miss the grooves on the pole and end up pushing the whole unit down too far so that it hooks onto the base of the glowplug, hence creating a short. If this happens, you'll know it pretty much straight away - your FADEC will die.

It's a really simple thing to get wrong without even knowing it - and it's pretty fatal.

Hope you get her sorted...

BJ

Hi Guys,

I just have a quick question, What size is the restrictor diameter ment to be in the bearing lube line? I thought I read somewhere that it is dia 0.4mm but I'd just like to make sure (for jj1400).

Cheers,
Paul.

It is a 26 gauge hypo needle cut down.

Noticed a little orange glow the last evening in the low light so took a pic, wonder what it is ?

Just looks like the normal 5-o'clock hot-spot to me - Smithy?

You should fire it up just after dark - you can really see where the hot-bits are http://www.youtube.com/watch?v=Nh0xpEQlAK4

BJ

Xairflyer, Mark, BJ and others

Well, after unsuccessful starts in the airplane again, I removed the entire turbine and accessories from the aircraft and set it up on the bench.

I attempted another start and after 'ignition' was displayed, removed the plug wire and Voila! it continued to cycle as normal. (no 64200rpm)

The glow wire does have a lot of EMI coming off it out to 3-4" from the wire while the ignition cycle is on. using an alternate ground wire from the plug to the case and case to the ECU plug ground cable didn't help.

I confirmed this with a scanner/receiver set to around 500khz. I had a strong signal all along the wire 3-4" away back to about 4-5" from the ECU. The ECU had minimal EMI.-so that's good.

So, at least I know what I'm dealing with-EMI

So, I will re-visit the twisted wires, look for shielding to encapsulate the starter and glow wires. It's probably getting right to the hall effect sensor vs the wiring.

not sure why it all started.

I also changed out the glow plug.

Jack

Try lowering the glow power 5 or 6 and pull the element out pretty far. With the stock OS A-3 34 to 36 works good. The thermocouple will also cause this problem if it is too close to the Glow plug as well.

In the bobcat as the fuselage is narrow I wrapped the glow plug and starter wires in an aluminium screening tape, it is a sticky back aluminium tape sold on a roll, if you are not sure what it is like have a look at my website, I sell bits for an ultralight that I fly & distribute and we use it for electrical screening and heat protection of fuel/oil pipes.

I also use it to protect inside of a fuselage from turbine heat.

www.xairireland.com select the aerobits button on the left then buildparts and then electrical link and scroll down through the items.

You might be able to find a similar product near you.

Good to hear that you've at leasted sourced the problem

Now you just have to figure how to get it started sans having to remove the glow-lead after the gas pops off...

BJ

re-twisted all the wires, and used a 3/16" ID ground strap to put around the Plug and ground wires for about 15". I grounded the braided wire to the plug ground and quick disconnect on the plug-It's a brass cap used for remote starts that requires only an 1/8 turn to lock it on.

Now all works well. Still some EMI but only about half as much is seen on my receiver, and this doesn't seem to cause any problems. so far so good.

will have some pics soon

Jack

Just gotta love them lil rogue electrons, huh?

LoL

BJ

hi guys , I have a jj1400 and want to put it into my 35% yak (as a turboprop).
I need a turboprop part as i have the turbine, jet joe does not make one as of yet. so does anyone know of who makes one seperate of the turbine.

I really dont want to have to bue another turbine as i like the jet joe.

thanks chris

Here's a couple of pics of my EMI fix on the Plug wire
the other end of shielded wire has been subsequently secured

hopefully I'm back in business

Jack

Heya Chris.

I'm not sure how well you'll go with your project.

AFAIK, TurboProps run the Turbine 'backwards' i.e. the inlet to the compressor comes from the rear, and the exhaust comes out the front - diverted by backwards facing curved exhausts. Have a look here: http://www.waoline.com/detente/hobby/hobbyturbines.htm

In addition to that, you'll notice that the Turbines shaft (from the exhaust end) feeds a gearbox arrangement - I don't think that that is simply a 'bolt on' attachment - your Turbine's shaft would need to be replaced with a longer one with the correct drive-gear etc. attached.

It would be interesting to read how you get on.

Please keep us posted...

BJ

Hmmm...interesting pics Jack.

Your Turbine is actually the dead-opposite of a JJ-3000. All your tubes come out of the Starboard side of the donk, whereas on a 3000 they all come out the Port side. Not that that's an issue - just an interesting difference.

One thing I do notice in your test-bench pic though is that your RPM sensor lead is running right past the fuel pumps 'hot' leads terminals. I would move it so that it's pretty much in 'fresh air'.

Also noticed that your glow ground lead is under the glowplug itself (?) May not be an issue, but I run mine to where the Turbine is bolted to my steel mounting bars, and on the opposite side to where the RPM lead comes out of the Turbine.

Either way, I'd get that RPM sensor wire as far away from any kind of wiring as possible. That's the one that will pick up any stray EMF, and if you're firing the Turbine up with it right across the fuel-pump contacts, it's not going to be doing you any favours.

I've reconfigured my test bench a couple of times now - and ended up starting with putting the FADEC in the best possible position so that the RPM sensor lead would have a clean run from the can to the FADEC without crossing any other leads.

Might be a bit difficult in an airframe scenario, but you really do need to keep it as far away from any other wiring as possible. It's a fairly sensisitive thing.

BJ

as from what ive seen the wren is normal turbine with a second stage gearbox for the turboprop(no direct connection from turbine to turboprop)

i could be wrong but it looks like it is a bolt on unit

I'm sure there are other differences. For one, the turbine wheel is different for this application.

What do you think,is it good decision to buy Jet Joe engine(JJ1800 or JJ3000)?

I am in huge dilema.

Size of the turbine depends on what size aircraft you wish to fit it in

Yes - I was going to ask the same question as Xair - what are to going to put it in?

I guess there's two main things to consider right up front:

1 - the weight of the aircraft you are trying to push. An all-up Weight/Thrust ratio of 1:1 is more than plenty of power for some flyers. e.g. A 10kg aircraft (including the weight of the Turbine + Fuel etc) should fly ok on a 10kg Thrust Turbine.

2 - what dimensions do you need to work within? There's a fair bit of physical size difference between an 1800 and a 3000. Go to the JetJoe site and check the total length, diameter and weight of the various thrust Turbines and maybe work backwards from there.

And don't forget, a JJ3000 producing 13+ kg of thrust is going to drink fuel like a fish when comapred to a 8kg thrust JJ1800. So you would need to decide on what sort of flying time you are looking for and then work out what amount of fuel you'll need to achieve that time. If you use 0.8 kg/litre of fuel, you won't be too far out. For example, a JJ3000 drinks about 16oz of fuel per minute on full noise. Thats about 473ml per minute. Call it 500ml = 1/2 litre of fuel per minute. A 5 minute flight would therefore require somewhere around 2 1/2 litres of fuel - make sure you calclulate enough left over to land with, or you'll be dead-sticking it in all the time LoL And don't cut the calculation too fine - you might need to abort a landing and go around again - you'll need fuel for that. Better to land with left over fuel rather than crash due to no fuel...

Continuing with this example, apart from 2 1/2 litres of fuel adding around 2 kilograms of weight at take off, you also need somewhere to put it. Try to visualize what amount of space 2 x 1lt coke bottles will take up in your airframe.

A JJ1800, on the other hand only consumes around 9oz of fuel per minute - roughly half the power for half the fuel consumption.

What kind of craft are you looking at powering?

BJ

OK guys, here are 2 short video's I shot this morning using my wife's camera. ok I admit it's not the best but going to try again later to make a better video.



This is the start up:

http://www.youtube.com/watch?v=maeFkiTqXcU


And this is the run up:

http://www.youtube.com/watch?v=hhbZdm_GCI8