Vettster

Hey Kingtech experts.. I hope you can shed some light as to why all of a sudden there are large yellow flames coming from the exhaust pipe and it is glowing red hot!! It eventually spools up and the tail cools down. This happen quit suddenly over the last 3 starts. First start was just a bit of flames... second start there was no mistaking the flames and took longer to spool. Third start took very long to spool and produced flames about 1.5 feet long. Unfortunately my GSU was not with me so no reading are available. Once fully spooled up it performed the same in the air. Seems to be a ramping issue

Any thoughts? What can I do to correct this?

Thanks!

Ps... This is on Diesel with Shell 560. 20c 10v battery

chuckk2

Talk to Kingtech?
Sounds like a lubrication related problem to me.

mr_matt

My Feedback: (10)

Turbine wheel rubbing? Distortion of the aft EGV causes localized rubbing, this slows acceleration artificially and the ECU over compensates on pump voltage. Once everything heats up the rubbing goes away. Does it do it on a second (immediate) start with a hot turbine?

Vettster

Haven't tried starting it immediately after running. Though I will take a look at it now for rubbing while its cool.

Thanks

Vettster

oops! I thought I had posted this under the Kingtech help forums

Vettster

Thanks Mr Matt... You are correct. The wheel does not turn freely so Im guessing the bearings are gone. There's no one to blame but myself as I ran 2 stroke oil early on. When the 100 first came out there was wide spread rumor that 2 stk oil was ok. Well KT never made that claim and went as far at put it in writing.. to late for me though. lol But Now I can get the upgraded compressor wheel done at the same time

Joe Westrich

My Feedback: (95)

It's a bummer that you have to send it in for repair.... However, it is refreshing to see someone take responsibility for their own actions. You see less of that in today's world.

Cheers

Pepperpete

Yup well done Vetster.

mr_matt

My Feedback: (10)

I have never seen bearing wear cause flames on start up. Is the turbine making funny noises when it is finally running normally?

basimpsn

My Feedback: (5)

I think Kingtech engines are sensitive to certain brands of oil. I ran out of turbine fuel and use a friend of mine's fuel but after the flight my engine wouldn't cool down and turning the compressor by hand feels gummy, I quickly drain the last 50 ounce out of my tank and ran it thru which fix the problem. Not sure what brand oil my friend was using.

P.S Because of the gum-up bearing during start-up will cause excessive flames but will start eventually.

CRX Turbines

How many hours on the motor? I highly doubt you caused this issue with 2 stroke oil. This will be an argument to go on long after the cows come home and leave again. All of these motors are similar in many regards but different enough to say that they are branded with different names. When you have it taken apart, since you have already been forthright in saying that you ran an oil not approved by the manufacturer, it would be interesting to see the condition of the chamber. The bearings might have overheated and then the issue arose not so much that the bearings caused the problem, so it might be something unforeseen or undiagnosed yet as to what caused this.

Andy Fioretti

chuckk2

Anyway Your problem reminded me of a problem with turbochargers called "coking"

http://www.exxonmobil.com/lubes/exxo...OilCoking1.pdf

What's interesting is that the same process was once considered to be helpful
in extending the engine life of "worn engines"! The varnish deposits, when not take to extremes,
did help. Interestingly enough, I have two vehicles, both gasoline powered that can have
problems. One has a supercharger lubricated with "turbine oil", the other a water cooled turbocharger
that is lubricated in common with the engine using synthetic 10W30 oil.

mr_matt

My Feedback: (10)

Yes I can see this, but in my experience anything gummy in the bearings gets washed away pretty quick. The OP says he was getting it on every start up.

What I HAVE seen is distortions in the rear bearing housings, EGV, etc or of course some schmutz that gets on the ring and starts to transfer metal from the turbine blade to the EGV ring, that gets worse and worse. These caused flames on start up.

basimpsn

My Feedback: (5)

That could be the case.. but I'm seeing it more often with my friends engines and certain brand oil. after using X brand now they can't start the turbine without turning the compressor by hand before flight.

Vettster

[QUOTE=mr_matt;11808420]I have never seen bearing wear cause flames on start up. Is the turbine making funny noises when it is finally running normally?[/QUOTNope.. Sounds perfectly normal when all when fully spooled and in the air.

Yes gummy would be a good way to explain how the wheel feels when I turn it

[QUOTE=afioretti;11808739]How many hours on the motor? I highly doubt you caused this issue with 2 stroke oil. This will be an argument to go on long after the cows come home and leave again. All of these motors are similar in many regards but different enough to say that they are branded with different names. When you have it taken apart, since you have already been forthright in saying that you ran an oil not approved by the manufacturer, it would be interesting to see the condition of the chamber. The bearings might have overheated and then the issue arose not so much that the bearings caused the problem, so it might be something unforeseen or undiagnosed yet as to what caused this.

Andy Fioretti[/QUOTI will check the hours soon. Just got home. But it not a lot. I will not be taking this engine apart. I will let KT do that and add what ever they find with the operation info I give them so thay can add it to their data base.

actually only in the last 3 starts.

Thanks guys for your input... Im going to head into the garage now and this time with the GSU hooked up Ill start it and video for your analysis.

Trevor

Vettster

Video on the way guys.. Its not a gumming problem. Its a serious coking problem. There is white residue everywhere. The wheel was difficult to turn at first but after about 20 turns it started to free up, so I thought Id try to start it. You can see in the video the results. Once it hit 850c I shut it down and the engine just seized up and would not go into to cool down. I had to put the blower to it and MAN does the diesel make a lot of smoke.

I just changed from 2 stk oil to shell 560 at the beginning of the flying season (3 weekends ago) and all of a sudden this!! Its a no brainier that I was better off with the 2stk oil... but it doesn't matter now as I now have 2 gallons of KT oil on hand. I will for sure be dumping fuel thats in her now.

Any suggestions guys? Should I try flushing the bearing out with fresh fuel/KT oil and try again?


https://www.youtube.com/watch?v=I5yQ...ature=youtu.be

Vettster

sorry guys.. I screwed up and didnt get the video of the start. Nothing to see but 2' long flames!!!!

mitchilito

My Feedback: (7)

Boy, would I like to take that engine apart and have a look around.

mr_matt

My Feedback: (10)

What oil were you using??

Vettster

aeroshell 560. Engine only has 14hrs on it. I have no doubt that the oil is the cause since it was only 3 weeks ago that I changed to that oil.

The engine cooled down again and the wheel was stiff. 20 or 30 turns again and it now spins freely.

So How do I flush the bearings.. Just stand the motor on end and keep priming while turning the compressor?

The girlfriend says "get into the garage and get the gum off your balls!" LOL

gunradd

My Feedback: (9)

I have a ton of hours on my kingtech180 with aeroshell 560 and its doing great. Nothing wrong with 560. stop messing with it and send it to Dirk at Kingtech before you cause more damage.

FlyEng

My Feedback: (5)

My thoughts as well.

Vettster

Me 3

basimpsn

My Feedback: (5)

Geee!! the back end of that engine looks bad lol.. from the looks of the turbine wheel and the cone..there is now some serious rear (bearing cooking) worse it's Kero start. That means if there was repeated hot start eventually the rear bearing is going to bake. My friend have the Propane start version so it less heat on start up.. I wouldnt start it again, time to send it in.

P.S I would send it with all supporting equipment so Barry can find tune it ...That's a tough engine lol.

Good luck

mr_matt

My Feedback: (10)

That looks more like the EGV and bearing retainer is distorted from over heating and the rear bearing is hosed.

Aeroshell 560 did that?? I find that incredible.