BJ64

That's entirely your choice.

But... you can crash a $20,000 plane just as easily as you can crash a $1,000 plane....

http://www.youtube.com/watch?v=OcuHOU0VnC8

BJ

rorrock

JJ arent then only turbines that fail.. a jetcat did at a jet meet here..
There has also been issues with Kingtech's out of the box..

AdriFlyBoy

What do you think about buying jetjoe 1800 from jetjoe US(not from China)?Are they tested before selling?

rorrock

If you are talking about mark at [link]http://jetjoecentral.com/index.html[/link]jetjoe central.. then yeah. he is pretty good with the jetjoe's...
Even if you went a king tech I'd recomend mark as he's just a pretty good guy all around..

AdriFlyBoy

Yeah,I thought about buying one from him.
So,it is much better than buying from China?If yes,it is great for me!

dw_crash

My Feedback: (6)

The ONLY way to buy a JetJoe. Mark goes through the engine and then sets it up and runs it. You then get a tested, running engine.

DW_Crash

AdriFlyBoy

Ok,thanks guys!I will see what are my other options and then make the right decision.

soupcandogs

Xairflyer, I would like to take a minute to shake your hand! I have had a real hard time getting my jj1400 running correctly. I recently got my engine back from Gabe here in the states for a vibration issue. After finally getting it back in my jet I too got the 64k reading on the monitor on start up. I too tried everything like completely tearing the jet apart to reroute wires and such. I was ready to side arm this turbine into the dumpster after all i had been through. Low and behold here you are with the solution 3 minutes after i logged in.I put the ground eyelet under the gloplug and presto! It now starts and runs perfectly. If only I would have checked this thread before all the crap I just went through. THANKS MAN!!!!!!!!!!!!!!!!!!

Xairflyer

My Feedback: (1)

The beauty of the web and these forum's being able to find answers while sitting at your computer drinking tea

I think if you have info that may be of use to others post it ! that is why I put up the thread on rebuilding my turbine, I have had loads of emails from guys since who have got something out of it, unmasking one of the big secrets in the turbines world [sm=teeth_smile.gif]

Xairflyer

My Feedback: (1)

Well I have been playing around with preload springs & spacers (to learn more and because I can't leave it alone) I found a few times that my preload was not there (sticking) so when checking the fit of the spacer and spring in the tunnel I found the spacer to be tighter than I would like.
Having spoken to Smithy who said it should really fall out under it's own weight, I decided to put the spacer in the lathe, turn it down and polish up the finish. It now runs must more freely in the shaft tunnel.

Having got a new tunnel in the post recently from wren for my Wren54 I noted no rear O ring groove.
Talking recently to a friend who has built a KJ66 plus reading a few things on the GTBA forum I thought about removing my rear O ring as every time I remove the preload spacer I find bits of O ring on the side of it. I dont think the groove in the Jetjoe tunnel is deep enough for the O ring as it normally needs to be shaved off a bit when new.

I took a fit on Saturday night before I went to bed to take it out (knowing I was going flying next day)
I have one of the mick reeves quick release turbine clamps on my Boomerang so taking the turbine out is easy, I just then take of the front starter cover (leave it connected in the plane) and unplug my rpm wire and festos.

With a permanent marker, I mark one of the turbine blades to NGV, and one blade of the compressor to intake, then I mark the spinner nut to the compressor, I remove the spinner nut (left hand thread), and then mark the shaft position to the compressor, tap the shaft out through the compressor withdraw the turbine wheel and shaft.

I then pulled out the O ring and cleaned it all up and re assembled by fitting the compressor onto the shaft and lining up the marks. I have found you need to offset the compressor on the shaft about 3mm as the tightening of the spinner nut makes it turn slightly on the shaft. Check the turbine blade to ngv marks and the compressor to intake marks all line up and you are good to go, if not loosen it and do it again.

Had three flights yesterday and noticed a big drop in EGT's about 60deg, with no drop in thrust, so I am assuming because my preload is actually now working much better. So for now like the idea of no rear O ring.

AdriFlyBoy

Xairflyer,I sent you the PM.

BJ64

Any idea why the O-ring is there in the first place, Xair?

BJ

Xairflyer

My Feedback: (1)

From what I have read it seems it was noted that turbines fitted with O rings ran quieter and also helps to stop the outer case of the bearing from rotating.

If not using a rear O ring then you would need to be certain the bearing is a good fit in the tunnel. My old Jetjoe tunnel was 16.01 at the front and why I fitted a new one when I rebuilt it, the new one I have for my wren is 15.99

vortex00

My Feedback: (22)

Anyone have any experience using some type of carbon cleaner injected in the fuel line to clean up a suspected fuel ejector?
JJ or any turbine.
vs disassembling the engine?

Jack

Jetbono

Thats a first one for me , I never heard of this on micro turbines..
I think you might still have to take the engine apart

Xairflyer

My Feedback: (1)

Even when on the bench fuel needles are very difficult to clean, most turbine manuf would replace it rather than take the time to try and clean them. So not much hope doing it without dismantling.
Easy enough to strip down, check out my trubine stripdown thread if you have not done it before.

f6hlct

My Feedback: (4)

I have just purchased a JJ1200 used, and am about to start it up for the first time. I can spin the turbine by hand and it feels smooth, but it has more drag than my JetCat. I am not new to turbines, but I have concern about trying to start it in this state. I have tried to spool it up with the hair drier just to get a sense of how much drag there is, but it does not spool at all. I also noticed that there is no preload movement when pressing in on the exhaust turbine. Is this just a case of dry bearings, or is this telling me something more.

Xairflyer

My Feedback: (1)

It depends on how long it is lying up, yes it will seem stiff if the bearings are gummed up, also the preload could be stuck, I would strip it, you only need to undo the front spinner nut and pull the turbine wheel/shaft out as one unit, that way you will have access to the preload as well.

f6hlct

My Feedback: (4)

Thanks for your reply. I guess I will have to delve into the turbine at this point. In you rebuild thread, it was not clear if you use Thread Lock on the Spinner nut. I do see your recommendation to put oil on the mating faces of the nut and compressor wheel in the following statement. “ tighten the compressor nut adding a slight smear of oil on the face to prevent fretting”

I will let you know how things are going.

Xairflyer

My Feedback: (1)

No, I have never fitted thread lock on the spinner nut and don't think it is needed, you do want this nut to loosen before the turbine one and thread lock may prevent that from happening.
I just tighten to my own feel, but there is a torque quoted somewhere in the stripdown thread. Remember left hand threads.

Post 2676 above basically goes through what you need, if you want to get at the front bearing then you will also have to take off the front intake.

I bet the preload is bunged up with bits of dirt and O ring

Jetbono

Hey all ,

I have jj1400 which has no filter ringbehind the diffuser and also no mesh , I want to run this engine, will the lubrication still work fine without the ring and mesh or will I get no air pressure to help push oil in shaft tunnel ?

f6hlct

My Feedback: (4)

Well I took things apart and reassembled in just a little over an hour.  I also fixed a few things along the way, but overall, it was not as big a job as I would have thought.  I now have the preload spring back as expected, and look forward to the run-up.  It will have to be another day, as I do not want to scare the neighbours near dinner time.  As for the torque on the spinner nut, I have worked on many small engines, and I have a good sense for what is right.

Thanks for your help.

Dave

Xairflyer

My Feedback: (1)

My JJ1400 dos'nt have it either, and anytime I take it apart the back bearing seems to be well lubed and inside the tunnel there is always a coat of oil. If the back bearing was'nt getting any oil it would'nt last very long!

Jetbono

Thanks Xairflyer

I will run it has it is then .

Cheers

Jetbono

Hey all ,

Does anybody have a second hand JJ1400/1200 Starter motor with clutch for sale ?

Please PM me if so ..

Thanks