RE: JetJoe OWNERS thread
 

Yes there seems to be so many guys out there who said they have one and they are crap, so I'm sure they would be more than glad to sell them cheap to get rid of them, anyone got any for sale ?

RE: JetJoe OWNERS thread
 

Guys the new JJ 3000 is out now intro price of $1900.00 for full auto start ECU, accessories, and fuel pump.

RE: JetJoe OWNERS thread
 

Since this thread is 3 1/2 years old, I'm sure anyone who bought one of these "engines" and wasn't happy with their purchase unloaded it a long time ago.
It is interesting reading though, all the twists and turns needed to make one of these things run.
You guys have more patience, and free time, than I do.
BRG,
Jon

RE: JetJoe OWNERS thread
 

Biggest problem with people who buy JetJoe engines tend to be first time turbine users, (I was one of them) a lot of the problems could have been avoided with expert help.
I now can have any of them setup and running perfectly in as long as it takes to bolt it on a test stand or in a model.

I bought a S/H one from a guy last week for £200 he said it never ran, just went on fire a few times:D and been lying in his shed for 2yrs, when I looked at it the ecu had been fried, it needed a new starter and a good look over. Cleaned it up, new pipework, used my ECU, new starter, new plug and it fired up on third attempt, only changed one backscreen parameter from mine and it now runs perfectly.:D

RE: JetJoe OWNERS thread
 

Tell me this, Does the turbine come with a setup, run and trouble shooting manual like all others I've seen? Or does JJ rely on RCU for this function? As you say.."newbies" seem to be their market. (I won't say those in the know know better)

"Can I download a operation manual for it?"

Dave

RE: JetJoe OWNERS thread
 

Xairflyer,

I concur. JetJoes do take some experience to get running on your own. I cut my teeth on turbines with a JJ1400. By the time I had it purring, I understood turbine operation.

A lot of hiccups can be avoided, as stated many times in this thread, by buying a engine from the two US vendors, Australian, UK or NZ vendors that setup and run the engines prior to shipping to the customer. A couple extra bucks saves a lot of learning/fiddling around.

And, to be fair, every one of my 5 turbines took tweeking to get to operate smoothly at my flying conditions (humidity, elevation etc.) The ECUs are not smart enough yet to 'AUTO TUNE' or 'AUTO SETUP'. They probably would need a couple extra sensor to do that.

DW_Crash

RE: JetJoe OWNERS thread
 

I think if it is bought direct from JetJoe you get the turbine, ecu and bits and you figure it out yourself, i'd expect that the ecu comes with its manual, I have never seen a JetJoe manual as such, but they may be one.

I have seen four different ECU's supplied with the turbines, each will have its own setup, mine has the gasper Au-540 same as supplied by wren before the newer model came out.

You will find that the owners who have had success with these turbines either know what they are doing or they have bought it from one of the Better JetJoe dealers who set it up before they give it to the customer.

RE: JetJoe OWNERS thread
 

"Does the turbine come with a setup, run and trouble shooting manual like all others I've seen?"

Guys,
If you're after a reasonable setup manual for the JJ's 12/14/18 which is actually written in English rather than Chinglish, Rob and I have come up with a useful one for the relative newbies.

I can supply one for you, just PM me and I'll shoot one off to you.

I'll be doing one for the JJ-3000 in the not too distant future, watch this space.

Cheers,
Smithy.

RE: JetJoe OWNERS thread
 

I have two jj the 1400 and 1800 Ive had problems with the 1400 ,was still under warranty a jj central Mark replace it no questions asked. I felt that the service was great, thats why im getting a 3000 as far a resale, im in this for my own personal flying pleasure. If I happen to have sale one of my plane with a jj in it, I would welcome any interested buyer out to the flying field. thats the only way I would do it. sort like see for your self type of thing.

RE: JetJoe OWNERS thread
 

Hi all,
I first time join your forum. But need a help from your experiences.
I got a jj-1200 with a start problem. Some start attempts with semi auto ECU were failed due to high EGT over 800 degrees. Engine disassembly is good. JJ support told me increase the max. temps to allow rotor runs up to idle. I think this is the worst means and suspect ECU setting should be the cause.
In my ECU the start point is auto+2 and start ramp is 002, are them ok?
What is the best rmp at which fuel come on? every time fuel in fuel line can't go into the engine until PW value approach to 70 because starter make the rotor runs up to 14K rmp within 2s while fuel pressure seems not overcome the air pressure at this point. I have to disengage the starter intermittently to allow fuel in and speed not drop too much. But the time taken by this process make higher PW value and surge fuel goes into CC.
Waiting for your good idea!

RE: JetJoe OWNERS thread
 

Hello

Which pump are you using?

Good Luck

RE: JetJoe OWNERS thread
 

What pump and ECU are you using ?

My settings are Auto+4 and 002,

You should not get that high of EGT, you must be getting a hot start, could be too much gas or not being turned off, it should be off at around 25K.

The fuel is turned on by the ECU registering 100°c from the thermo probe, is your probe calibrated correctly? it should be within a few diegrees of the actual temperature you are operating in.

RE: JetJoe OWNERS thread
 

I use JJ pump powered by 7.4v li-po battery.

ECU brand is Regal semi auto FADEC. I really want to know what is the meaning of AUTO+X(X=0-8)? does the greater number set less initial fuel capacity?

Normally I turned off gas at once fuel began to burn. I still wonder why fuel can't go into engine at pump PW lower than about 70. One time a funny thing that fuel in line was backward to fuel tank then air bubble raised in tank occurs when starter make rotor run at 14k rmp with lower PW value. Gradual increasing of PW should be given for a suitable fuel/air ratio. How can I do? Should I reduce fuel ramp to 001?

JJ turbine casting is not fine because many mold lines still remain specially on the trail eadge of blade. It severely affect turbine effectivity. I have to finish it with small file.

Thermo probe on my engine has a little error within 10 degrees higher than atmosphere temp.

RE: JetJoe OWNERS thread
 

The JJ pump (or at least the one I bought) is very poor and will allow fuel to be blown back by combustor pressure.

Even JJ themselves suggest that these pumps are only suitable for bench running (and even then I'd say you'd be wasting your money). You'd probably get much better results with a *decent* fuel pump.

RE: JetJoe OWNERS thread
 

I have heard the JJ pump is not very good and most like me use the fliteworks 200.

The pump start point Auto+ 2 etc, is the minimum pump voltage where it starts to turn, mine likes Auto+4 which is the flightworks 200 pump and a 2 cell lipo, the JJ pump may need more or less.

The pump start ramp sets the rate of increase in the fuel flow during start up, mine is set to 002 but there are also backscreen parameters that effect this also ramp1, 2 & 3.
The value set here will effect how fast the turbine gets to idle, a low value may make the turbine longer to start and settle at idle but will prevent Hot/wet starts that the higher values will cause.

10deg is a lot of difference in the probe as the error will increase higher up the scale, in the back screen parameter 1 you need to increase the value by 5 (2deg per unit)

RE: JetJoe OWNERS thread
 

If the engine is only running at 14k, when fuel is introduced, the engine will be unable to accelerate on it's own and will give a hot start. Normally the fully auto ECU is set to cut off the starter motor above 20k so I would suggest keeping the starter motor engaged and leave the gas going until you hear the engine start to run of kero, then disengage starter and switch off gas.
Your ECU settings look quite normal and I would letting the starter motor help with the RPM some more ebfore changing too much.
I use flightworks pump as well.
My 2c.

RE: JetJoe OWNERS thread
 

Thanks Xairflyer.
Two start attempts were done just now per your recommended setting. Unfortunately EGT is still high and does not reach to idle speed.
Engine hangs at 33K rmp with PW wandering about 106. This may be due to EGT 770 degree or pump poor pressure which limits fuel ramp.

Is it necessary to replace with flightwork pump to finally address this issue?

RE: JetJoe OWNERS thread
 

It probably is the cause as Xjet mentioned, I know the JJ pump is only for bench running, but it should still allow it to run.

Are you manually controlling the starter ?

What are the settings in the back screen for ramp 1, 2 & 3

RE: JetJoe OWNERS thread
 

I use flightworks 200 pump on jj1400 and propane to start at lowest setting. I use no gas solenoid or onboard gas. I have a checkvale in gas line. I manualy turn off gas at 29-30,000. You my have a fuel leak under your front cover or perhap an internal leak as 100 seem a high number at idle. diferent pumps, injector needle sizes,fuel filters will change these .
"Cycle","Page","Aux","Temp","RPM","Throttle","Pump ",#2008-09-17 18:30:24#
91,220,0,556,45000,257,66 idle
91,228,0,636,161000,996,332 full
You are better to use power max or a butane to start as it wilkl start slower and warm more even and your pump will not overshoot idle as much.

RE: JetJoe OWNERS thread
 

I use JJ pump only for bench run so far.

Yes I manually control the starter because of semi auto ECU. Now I also suspect the weak starter because the engine can be motoring only by starter at max. 16K rmp, is it not enough? Normally I engage the starter until 31K rmp. Do you know the detail of full auto start such as fuel on speed, starter disengagement speed and their related PW value? thanks so much!

Start fuel ramp is setting at 002 in ECU. I disassembled the engine last night and no abnormal findings except that rear bearing inner race discolors due to high temp. What can I do to rescue my engine?

RE: JetJoe OWNERS thread
 

14K rmp is engine speed by starter driving only.

I usually turn off gas at once kero is burning and keep starter engaged until 30k rmp. is it necessary to supply gas until 30K like idleup1 said. But I don't know why the rotor accelerate so slowly. Starter or drag on the rotor?

RE: JetJoe OWNERS thread
 

I turn my gas off at 25K, that is all I do the ECU does the rest, if using the gas valve the ecu will also turn it off a 25K so is long enough.

RE: JetJoe OWNERS thread
 

If you have the engine apart still, try checking that you have even fuel flow to all the fuel injectors. You can do this by taking the fuel ring, running gas through it and then lighting the needles (it takes only a veyr small amount of gas). If you have an uneven flame from one or some of the needles or no flame, then that will be causing a hot spot, which may be aligned with your EGT probe.

The ECU will be holding the rpm due to high temperature. If the pump was a limiting factor, then the PW would continue to increase as the ECU tried to get more fuel flow.

RE: JetJoe OWNERS thread
 

I have a question about my latest JJ1400:

The engine runs and starts OK however I cannot reach max RPM of 160,000. It reaches max 138,000. The EGT at idle is 550, at mid throttle like 650, above 120,000 RPM egt reaches suddenly upto 800 C. I am thinking: since the ECU is set at 800 C max temp this maybe the reason for not reaching max RPM. Shall I increase this setting to reach higher RPM's or shall I assume there is a mechanical problem with the turbine?. The balance of teh turbine is almost perfect...Another reason might be smaller diameter of the NEW exhaust nozzle creating higher temps at higher RPM's. Are such temps acceptable?.

I appreciate comments.

Murat

RE: JetJoe OWNERS thread
 

you must shorten your tail cone enough to get temp down under 750 or 700 to be safe. 42mm is the smallest I have.Stock motor will take 45 to 46mm opening probably.