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Wren 160 failures

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Old 02-24-2014, 11:03 AM
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jacojet
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Default Wren 160 failures

Wren 160 failures:

If you read this and have something to add, good or bad, please feel free.
I did try to argue the matter with wren before posting here and was told to "do your worst"
All the cases below is of relevance to the Wren 160 only (35 failed engines, and some of them twice!)


These are only the ones I know about. There will be lots of others.
Most if not all of the 160’s below, failed within the first 5 hours of use.
When repaired or upgraded they failed within the first 9 hours of use.
I have spoken to Leonie at wren about the failures, at first she admitted that there was a problem and then said I should not put words in her mouth when I mentioned it again. They refuse to admit that it was a wide spread problem.
The 160 was introduced in 2009, it came with a cast compressor that was discovered later to be unreliable and caused multiple failures by shedding its blades. An “upgrade” could be done; witch you had to pay for, and consisted of a machined compressor witch lasted longer, but still failed eventually. I think that the compressors are not to blame, but rather a design flaw. The air intake to the compressor is too shallow and allows the compressor to be buffeted by turbulent air entering the turbine (This is only speculation on my part, but does make sense). Wren certainly did not do sufficient development work and testing to predict the problem, and then when it manifested, did nothing to protect its customers and its product, but rather allowed it to run its course in the knowledge and hope that most 160 owners will not be aware of other owners with the same issues, and they capitalized on this by charging most owners for a repair and upgrade that should have been wren’s problem. Jetcat had a similar problem with their new P180, but they recalled and replaced all affected turbines with new ones, free of charge.

Now consider this:
Costumer 1 buys a 160 for a project and it takes a while to actually get it in the air. He then flies it a couple of times and everything seems perfect. Some time has now passed and he is now into his second or even third year, yet the turbine has only seen a couple of hour’s runtime. So one day he ventures out to the field with his jet for a flight or two and the turbine sheds a blade thru the fod guard and in some cases through the fuselage! Lucky for him it happens on the ground and the jet is not damaged. So he sends the engine to wren, who tells him, that since the engine is out of warranty they will repair it for x amount. The customer accepts this and also the offer from wren to upgrade the engine for x amount and do a kero start upgrade for free! He gets his engine back and starts flying it again. The engine flies for the rest of the year and about 7-9 hours, then suddenly fails again. The customer sends the engine back to wren. Wren then proceeds to quote the customer the full amount to repair it again. In total, the customer has had about 9-11 hours use of the turbine witch by then cost him the equivalent of two brand new turbines! And wren would have profited by selling the engine, and then by repairing it twice! Indeed, the 160 must have been the most profitable turbine wren ever made!

Customer 2 buys a brand new wren 160 and it too sheds a blade in its 4[SUP]th[/SUP] or 5[SUP]th[/SUP] hour. It too, gets sent back too wren. But as the turbine is only 1 and half years old, wren offers to repair it for free with the known defective compressor, free kero upgrade and no guarantee, or repair it with the “upgraded” compressor, but then charge the full amount for the repair and give a 12-month guarantee. What kind of solution is that?
Are they prepared to repair an engine with a known defective part for free? And by giving no guarantee admit that it is going to fail again?

Customer 3 also buys a new 160 and it also sheds a blade on the compressor, but since it is still under warranty it gets repaired with the upgraded compressor for free. Once the customer gets it back, it failed within a couple of hour’s of use. But now wren refuse to repair or even sell the parts so the customer can repair it himself.

Customer 4 buys a 160 secondhand with only 6 hours of use. (Now, bear in mind that wren has in various cases admitted that there was a problem with the 160, but has never issued any kind of statement or communicated with 160 owners, that a compressor upgrade was mandatory. So it would be easy for a potential buyer to buy a secondhand but low runtime 160, and not be aware of the danger it poses). This engine also sheds some blades and is sent of to wren. Because this engine is now 5 years old, even though it has only 6 hours runtime, Wren refuses repair or even consider a compromise where both wren and the customer can benefit by offering at the very least to repair at cost. At this time wren said that the parts needed for repair is no longer available in any case, so no repair would be possible, even if the customer was prepared to pay the full amount. Customer can of-course pay the full amount for repair and get a free kero upgrade! (If the parts where available)
No parts for a 5 year old turbine!!??

  1. Luis P - 1wren 160 serial nr: 56260809
WREN UNPROFESIONAL ... 160 Broken
Spain
ALARM .... a turbine with 10 hours of use ..... wren breaks unresponsive .... are you the owner of a wren 160? Be careful you can be very very expensive 200 dollars an hour flight


Thanks Wren for unprofessional

They do not repair or provide parts replacement solution

About Wren 160 ..... my whole relationship with Wren described in this thread ..... RC universe Wren's answer is negative.... never took care of their manufacturing error....






Tomorrow I will send you the serial number of my wren .......... I could not win with them



They are of the lineage of the legendary British pirates

2.Toby - 1wren 160
Bloemfontein SA
Toby lost a compressor blade and gave the turbine to Oloff. Refuses to even consider sending it to wren.

3.Gregory Donaldson- 4wren 160
Johannesburg SA
Bought 4 engines, 2 broke, sent 2 back for repair and 2 for upgrades, 2 failed again and was sent to Dean from aerial concepts. One is making a noise, so is not used, and the other now has about 7 hours, but is not considered reliable enough to fly anything other than a boomerang.

4.Frans van Niekerk - 4wren 160
Parys SA
Upgraded 4 engines after they failed, broke 1 after upgrade

5.Oloff - 2wren 160
Johannesburg SA
Got 1 engine from Toby and 1 new, sent both for repair and upgrade. Paid for upgrade to new engine in an effort to make it reliable! Paid for repair to other engine even though it had only a few hours of runtime.

6.Dean Groblaar - 6wren 160
Johannesburg SA
Sold 6 engines that failed and had to pay for repair, very negative responses from wren.

7.Jaco Strydom - 1wren 160 serial nr: 55280809
Sasolburg SA
Bought from Graham Dewaveren , failed after 4[SUP]th[/SUP] flight. Wren refuses to repair
According to records the engine received an ecu upgrade in 2009, witch the original owner paid for, within the first year because of flame-outs and inconsistent running. The engine then promptly failed on the 4[SUP]th[/SUP] flight. The engine was sent to wren for assessment. Now they state that no parts are available for repair!



8. Xantos - 1 wren 160 serial nr: 04080109
Bought a new turbine, it failed and was rebuilt by wren- 110310 and failed again

With due respects to Mr Dosu's different perspective to the whole Wren matter I would like to present some facts with regard to my experience with Wren.
I had one of the early Wren160s that shed a compressor blade .
Wren was good enough to replace the compressor wheel and rebuild the turbine in March 2012, I was still a little apprehensive about the repair and questioned Wren if they were sure that the replacement compressor wheel used in the rebuild was from a a new lot of compressor wheels.
The reply I got was most certainly unprofessional - Wren had NO record of the rebuild and therefore couldn't confirm whether the replaced component was indeed defect free. i.e. From the older lot of defective compressors or from a newer lot.
Two weeks ago the same rebuilt engine threw a blade again.
I have attached some pics from the latest incident.
Please bear in mind the engine was nowhere close to its service interval and thrust was limited to 112k RPM on the ECU
Wren of course has been gracious enough to request me to send the engine back.
The engine is back with Wren.
But the fact remains that Wren deliberately chose to ignore this matter and as a result I have a hole in my fuse and unnecessary damage sustained to the airframe.
One of the preceding posts refers to home repairs as a running/ticking time bomb
In my opinion how is Wren any better or more responsible?
Multiple reports of similar incidents with their 160 and the fact that they knew and accepted there was a problem with a component, should have initiated a recall.
Wren simply ignored the issue and wished the problem would disappear and in the process have simply endangered people’s safety.
So regardless whether the company is a handful of engineers with fantastic ideas or simply a Mom and Pop operation it certainly isn't acceptable to ignore the risk and the potential for damage
Any responsible manufacturer would have be expected to recall product that may have been released to the market with defective components.

9. Bigbri - 1 wren 160
Wren replaced the compressor and it failed later

10. NZJET - 1 Wren 160 serial nr: 031010
New Zealand
Wren 160 keeps exploding
He’s not the only one with a wren that keeps exploding..
I have had 2 wren 160’s the first I cannot tell you the SN of, lasted around 1 hour when the compressor failed destroying the entire engine.
Ron from wren replaced this motor with a brand new one, sn 031010 this motor had the new machined compressor design.

This turbine failed after around 4 hours. I believe the turbine wheel lost a blade. Wren would not repair any more but sold me parts to repair myself, which I paid $900 usd for but then they couldn’t sell me a turbine wheel so the engine sits as a paper
weight.

This is more about how crap the 160 is and the fact we have to keep paying to fix a engine that shouldn’t keep exploding. The story on my engine is the first one destroyed itself after 5 or so hours, ron replaced it with a new one which to went bang after 2 hours, sold me replacement parts for it (around 1k i think) and now i cant get a turbine wheel for it so its sitting as a door stop, i guess where it will stay!

11. Assimat - 1 Wren 160
Wren 160- 1 failure

12. Chatty c-makhija –6 Wren 160
India
All of the 160’s failed
Hello Jaco,

We had 6 wren 160s here in India, every single one of them failed. This was back in 2010 and wren repaired mine FOC for me. Unfortunately my friend was not so lucky and got a big bill from wren for the repair. After the upgrade I sold my 160 and the new owner had a crash due to different reasons.
Please let me know if I can be of any help.

Best regards
Chatty.
Failed out of warranty and repaired free of charge- Mike Murphy admitted it to be a manufacturing problem

13. In the haze -3 Wren 160
Idiot # 3. ( that is what he calls himself)
Cape Town SA
3 failed engines
Indeed, we have 3 160's that are lying in pieces with broken compressor wheels, too expensive to send back for repair.........



14. Jim Cattanach –1 Wren 160
Wren repairs out of warranty engine
I had a Wren 160 that destroyed itself in the air. It didn't have many hours on it, but was out of warranty. I sent it back to Wren.
Wren said it was too badly damaged to repair & sent me a new one, free of charge.
I thought the service I received was very professional.

Hi Jaco, I had a lot of problems dealing with Wren on previous occasions prior to the one where my 160 blew up. I decided, after getting nowhere with them, the only chance to get a satisfactory outcome, was to go public on RCU.
My case created quite a lot of negative interest for Wren & in the end, they gave me a brand new 160 free of charge, after admitting liability.
I would certainly be annoyed with the service you got & if a satisfactory solution was not forthcoming, would go on RCU & describe what happened & how you were treated.
Mentioning other cases of a similar nature, like mine, may help. They hate bad publicity.
I no longer have any Wren turbines & have no intention of dealing with them again.

Good luck
Jim


15. Phillip- 2 Wren 160
Damages his Viper when engine failed on take-off. Sent both in for repair and upgrade.

Still waiting to hear from wren.

Last edited by jacojet; 02-24-2014 at 12:12 PM.
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Old 02-24-2014, 12:03 PM
  #2  
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jacojet. You sent me a private message asking for my help & you have posted my PRIVATE REPLY TO YOU. It seems you think it correct & proper to post replies given in confidence, so in exchange, I will post your original PM to me, so everyone knows who you are.

================================================== ================================================== ================================================== =========================


Hello Jim!
I have a wren 160 that I bought secondhand with 6 hours on. On the 4th flight it lost some compressor blades. Wren is charging me 900 pounds for a repair. The engine was inspected by wren UK in December 2012 and the ecu was upgraded. It only lasted another hour after the upgrade and then failed. I would like to know how you resolved your issue with them and how they dealt with you, if you don't mind? I feel that they are not dealing with this in a fair manner as it seems there is a known issue with these engines. I am compiling a list of serial nr' s of failed 160's, and would appreciate it if you can provide the serial nr of your engine and any others you might know of. Also any advice or info on how to deal with this would be welcome.

Thanks in advance
Jaco Strydom

================================================== ================================================== ================================================== ================================================== ===================

I did indeed get a new replacement turbine, but may not have done, had I not mentioned it on RCU. However, in the end, Wren did the right thing by me.
I also object to being called idiot number 3. In my opinion, the only idiot on this thread is you.

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Old 02-24-2014, 12:33 PM
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Mentioning other cases of a similar nature, like mine, may help

Hi Jim, I am very sorry to have used your reply to me, I was not under the impression that it would not be ok? I did not call you Idiot#3, that was what In The Haze called himself, I have moved it. Yes, I might be an Idiot, but only for believing there is a right and a wrong. You might have been lucky and it worked out for you in the end, but what about all the others that has not been so treated?
I am sorry to have offended you, it was never my intention.
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Old 02-24-2014, 12:37 PM
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Sounds like a serious matter - I was very close to getting a Wren 160 myself.. However, to me, it looks like "idiot nr 3" is a nameless guy from Cape Town, South Africa - and that Jim tells Jaco that he may have to mention "other cases, like mine" on RCU to make Wren react. Am I reading this wrong??
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Old 02-24-2014, 03:26 PM
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It's sad to see a turbine company once regarded as one of the best companies to deal with get bad press like this.

I've never had a Wren 160 but I have had stacks of Wrens over the years without any real problems. It does seem the 160 is the only one of their engines with issues.
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Old 02-24-2014, 03:53 PM
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..................

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Old 02-24-2014, 05:01 PM
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Hello Jaco,
I guess I'm one of the IDIOTS who bought a Wren 160.
besides that there's not much to be said.
Wren's business ethics obviously are far from honourable .
Other brands have had compressor failures recently and they reacted far more responsibly by initiating a widespread recall .
Wren doesn't care and their attitude is " Do Your Worst "
We all learn from experience and I will never buy or recommend a Wren ever again
Xantos
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Old 02-24-2014, 06:54 PM
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Oh geez, here we go again!
This thread ran a few months ago - and now is back.

Seems that the OP wasn't happy, didn't get the response he wanted, or didn't get enough of a jolt from blasting Wren, so he wants some more ..... have seen a few of these posts.
YES, I had an engine fail, and YES it was taken care of ....... and YES I bought a second 160.

Having seen JetCats blow up, and knowing the time frames getting them taken care of .... but none of this washing of dirty laundry in public, I have to wonder about the OP's motives, certainly not for just educating the public!

Greg
Owns or has owned PST, Jet Central, KingTech and Wren
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Old 02-24-2014, 07:49 PM
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mavrick
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I had the same treatment 10 years ago with Wren would never buy another one, I have since had 9 new turbines from 2 different manufactures and been well looked after.
Cheers
Mav

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Old 02-25-2014, 07:48 AM
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When 2.4 was first introduced JR and Futaba had their share of problems and the consumer paid the price. These two companies never had a recall did they and it took the hobbyist to force their hand. The poster is doing the same thing and should be applauded.
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Old 02-25-2014, 08:35 AM
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Has anyone had an objective look at the motors both running and damaged to see what might be causing this issue and possibly correct it?

Originally Posted by flycatch View Post
When 2.4 was first introduced JR and Futaba had their share of problems and the consumer paid the price. These two companies never had a recall did they and it took the hobbyist to force their hand. The poster is doing the same thing and should be applauded.
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Old 02-25-2014, 08:58 AM
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Originally Posted by afioretti View Post
Has anyone had an objective look at the motors both running and damaged to see what might be causing this issue and possibly correct it?
The cast wheel, from a turbo wasn't meant to be spun or loaded as hard as they are in our engines. that's why the new gen engines have gone to a cnc wheel.


Now... to defend wren a little....

They don't offer a "life time" warranty like some companys do. the engines failed out of warranty... so it is what it is. a have a little wren 44 that ate a few sets of bearings, and they wouldn't warranty them. but, it doesn't make them a bad company. When you buy one of their engines, you know how long things are covered, and that you have to send it in to be worked on. so... if it sits in the box for a year... or it's second hand... or if you get mad because they wont send you parts... then it's what you agreed to when you bought it.


Now... stop whining like little kids, and pulling up the same BS... and go fly.

Last edited by Dr Honda; 02-25-2014 at 09:01 AM.
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Old 02-25-2014, 09:08 AM
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I own a wren and I find it to be a reliable motor. I was thinking about the 160 and now I don't know. How does warranty come into play here? If the motor has an underlying design flaw as it seems may be the case here, then fix it, dont cover it up and why would the motor not be covered. If I leave it in a box... I may not put it into a plane for 6 months so the warranty is out in some cases before its maiden flight? I would think that this sort of circumstance would be taken into consideration.

Originally Posted by Dr Honda View Post
The cast wheel, from a turbo wasn't meant to be spun or loaded as hard as they are in our engines. that's why the new gen engines have gone to a cnc wheel.


Now... to defend wren a little....

They don't offer a "life time" warranty like some companys do. the engines failed out of warranty... so it is what it is. a have a little wren 44 that ate a few sets of bearings, and they wouldn't warranty them. but, it doesn't make them a bad company. When you buy one of their engines, you know how long things are covered, and that you have to send it in to be worked on. so... if it sits in the box for a year... or it's second hand... or if you get mad because they wont send you parts... then it's what you agreed to when you bought it.


Now... stop whining like little kids, and pulling up the same BS... and go fly.

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Old 02-25-2014, 09:16 AM
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I have never seen a compressor come apart in this manner, CNC or cast. Has anyone dismantled one of these motors to see what the root cause might be?

Originally Posted by Dr Honda View Post
The cast wheel, from a turbo wasn't meant to be spun or loaded as hard as they are in our engines. that's why the new gen engines have gone to a cnc wheel.


Now... to defend wren a little....

They don't offer a "life time" warranty like some companys do. the engines failed out of warranty... so it is what it is. a have a little wren 44 that ate a few sets of bearings, and they wouldn't warranty them. but, it doesn't make them a bad company. When you buy one of their engines, you know how long things are covered, and that you have to send it in to be worked on. so... if it sits in the box for a year... or it's second hand... or if you get mad because they wont send you parts... then it's what you agreed to when you bought it.


Now... stop whining like little kids, and pulling up the same BS... and go fly.
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Old 02-25-2014, 09:45 AM
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Does anyone know the diameter of the 160 comp wheel?

JG
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Old 02-25-2014, 10:02 AM
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Originally Posted by jgracco View Post
Does anyone know the diameter of the 160 comp wheel?
They all start off at 160mm but get smaller with each run !
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Old 02-25-2014, 10:11 AM
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I think the question of diameter is definitely a valid one.. anyone know?

Originally Posted by Couch Potato View Post
They all start off at 160mm but get smaller with each run !
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Old 02-25-2014, 10:17 AM
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Originally Posted by afioretti View Post
I have never seen a compressor come apart in this manner, CNC or cast. Has anyone dismantled one of these motors to see what the root cause might be?
I suspect that the air intake to the compressor is too shallow. Air entering the compressor is too turbulent and is buffeting the blades. If you look closely at the attached photo you will see that the blade that is cracked, but not broken of, is bent in the opposite direction than what you might expect of a blade coming of because of material quality. It is clearly bent towards the inside, as opposed to the outside because of centrifugal force. That shows that a force was applied to the top of the blades, causing them to bent to the inside and eventually break.
Even 160's that was upgraded to the new machined compressor also failed, although some lasted longer because of the stronger compressor, they eventually fail, or will fail. This proves that the stronger compressor did not solve the problem but only prolonged the phenomenon.
Compare the intake bell with any other turbine, and you will notice how shallow it is.
Sorry, don't know the diameter of the compressor.
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Old 02-25-2014, 10:28 AM
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Well if this is the case then lengthen the intake. Correct? I am curious about the diameter and whether 126K is excessive for the design.

Originally Posted by jacojet View Post
I suspect that the air intake to the compressor is too shallow. Air entering the compressor is too turbulent and is buffeting the blades. If you look closely at the attached photo you will see that the blade that is cracked, but not broken of, is bent in the opposite direction than what you might expect of a blade coming of because of material quality. It is clearly bent towards the inside, as opposed to the outside because of centrifugal force. That shows that a force was applied to the top of the blades, causing them to bent to the inside and eventually break.
Even 160's that was upgraded to the new machined compressor also failed, although some lasted longer because of the stronger compressor, they eventually fail, or will fail. This proves that the stronger compressor did not solve the problem but only prolonged the phenomenon.
Compare the intake bell with any other turbine, and you will notice how shallow it is.
Sorry, don't know the diameter of the compressor.
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Old 02-25-2014, 10:38 AM
  #20  
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Originally Posted by afioretti View Post
Well if this is the case then lengthen the intake. Correct? I am curious about the diameter and whether 126K is excessive for the design.
I am no expert, but looking at the way it failed and comparing to other brands of turbines, it would seem logical to increase the intake length to straighten out the incoming air. But doing this might also decrease the intake area behind the FOD guard. RPM does not seem to be the problem, mine failed at 116000 rpm and another failed at 112000 rpm. Most of the failures in SA was at reduced rpm's.
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Old 02-25-2014, 10:46 AM
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I am sure someone with the math knowledge can chime in. Based on the reported RPM being lower (112 - 116), this does not sound like a material or workmanship issue. I have seen the 160 CNC comp wheel. It is a nice piece of workmanship. My first hunch would be to lengthen the intake and try a modification, even if to try a makeshift outer shroud to test the theory... if it resolves the issue then make an intake that is deeper.


Originally Posted by jacojet View Post
I am no expert, but looking at the way it failed and comparing to other brands of turbines, it would seem logical to increase the intake length to straighten out the incoming air. But doing this might also decrease the intake area behind the FOD guard. RPM does not seem to be the problem, mine failed at 116000 rpm and another failed at 112000 rpm. Most of the failures in SA was at reduced rpm's.
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Old 02-25-2014, 11:32 AM
  #22  
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Originally Posted by jacojet View Post
Wren 160 failures:

If you read this and have something to add, good or bad, please feel free.
I did try to argue the matter with wren before posting here and was told to "do your worst"
All the cases below is of relevance to the Wren 160 only (35 failed engines, and some of them twice!)


These are only the ones I know about. There will be lots of others.
Most if not all of the 160’s below, failed within the first 5 hours of use.
When repaired or upgraded they failed within the first 9 hours of use.
I have spoken to Leonie at wren about the failures, at first she admitted that there was a problem and then said I should not put words in her mouth when I mentioned it again. They refuse to admit that it was a wide spread problem.
The 160 was introduced in 2009, it came with a cast compressor that was discovered later to be unreliable and caused multiple failures by shedding its blades. An “upgrade” could be done; witch you had to pay for, and consisted of a machined compressor witch lasted longer, but still failed eventually. I think that the compressors are not to blame, but rather a design flaw. The air intake to the compressor is too shallow and allows the compressor to be buffeted by turbulent air entering the turbine (This is only speculation on my part, but does make sense). Wren certainly did not do sufficient development work and testing to predict the problem, and then when it manifested, did nothing to protect its customers and its product, but rather allowed it to run its course in the knowledge and hope that most 160 owners will not be aware of other owners with the same issues, and they capitalized on this by charging most owners for a repair and upgrade that should have been wren’s problem. Jetcat had a similar problem with their new P180, but they recalled and replaced all affected turbines with new ones, free of charge.

Now consider this:
Costumer 1 buys a 160 for a project and it takes a while to actually get it in the air. He then flies it a couple of times and everything seems perfect. Some time has now passed and he is now into his second or even third year, yet the turbine has only seen a couple of hour’s runtime. So one day he ventures out to the field with his jet for a flight or two and the turbine sheds a blade thru the fod guard and in some cases through the fuselage! Lucky for him it happens on the ground and the jet is not damaged. So he sends the engine to wren, who tells him, that since the engine is out of warranty they will repair it for x amount. The customer accepts this and also the offer from wren to upgrade the engine for x amount and do a kero start upgrade for free! He gets his engine back and starts flying it again. The engine flies for the rest of the year and about 7-9 hours, then suddenly fails again. The customer sends the engine back to wren. Wren then proceeds to quote the customer the full amount to repair it again. In total, the customer has had about 9-11 hours use of the turbine witch by then cost him the equivalent of two brand new turbines! And wren would have profited by selling the engine, and then by repairing it twice! Indeed, the 160 must have been the most profitable turbine wren ever made!

Customer 2 buys a brand new wren 160 and it too sheds a blade in its 4[SUP]th[/SUP] or 5[SUP]th[/SUP] hour. It too, gets sent back too wren. But as the turbine is only 1 and half years old, wren offers to repair it for free with the known defective compressor, free kero upgrade and no guarantee, or repair it with the “upgraded” compressor, but then charge the full amount for the repair and give a 12-month guarantee. What kind of solution is that?
Are they prepared to repair an engine with a known defective part for free? And by giving no guarantee admit that it is going to fail again?

Customer 3 also buys a new 160 and it also sheds a blade on the compressor, but since it is still under warranty it gets repaired with the upgraded compressor for free. Once the customer gets it back, it failed within a couple of hour’s of use. But now wren refuse to repair or even sell the parts so the customer can repair it himself.

Customer 4 buys a 160 secondhand with only 6 hours of use. (Now, bear in mind that wren has in various cases admitted that there was a problem with the 160, but has never issued any kind of statement or communicated with 160 owners, that a compressor upgrade was mandatory. So it would be easy for a potential buyer to buy a secondhand but low runtime 160, and not be aware of the danger it poses). This engine also sheds some blades and is sent of to wren. Because this engine is now 5 years old, even though it has only 6 hours runtime, Wren refuses repair or even consider a compromise where both wren and the customer can benefit by offering at the very least to repair at cost. At this time wren said that the parts needed for repair is no longer available in any case, so no repair would be possible, even if the customer was prepared to pay the full amount. Customer can of-course pay the full amount for repair and get a free kero upgrade! (If the parts where available)
No parts for a 5 year old turbine!!??

  1. Luis P - 1wren 160 serial nr: 56260809
WREN UNPROFESIONAL ... 160 Broken
Spain
ALARM .... a turbine with 10 hours of use ..... wren breaks unresponsive .... are you the owner of a wren 160? Be careful you can be very very expensive 200 dollars an hour flight


Thanks Wren for unprofessional

They do not repair or provide parts replacement solution

About Wren 160 ..... my whole relationship with Wren described in this thread ..... RC universe Wren's answer is negative.... never took care of their manufacturing error....






Tomorrow I will send you the serial number of my wren .......... I could not win with them



They are of the lineage of the legendary British pirates

2.Toby - 1wren 160
Bloemfontein SA
Toby lost a compressor blade and gave the turbine to Oloff. Refuses to even consider sending it to wren.

3.Gregory Donaldson- 4wren 160
Johannesburg SA
Bought 4 engines, 2 broke, sent 2 back for repair and 2 for upgrades, 2 failed again and was sent to Dean from aerial concepts. One is making a noise, so is not used, and the other now has about 7 hours, but is not considered reliable enough to fly anything other than a boomerang.

4.Frans van Niekerk - 4wren 160
Parys SA
Upgraded 4 engines after they failed, broke 1 after upgrade

5.Oloff - 2wren 160
Johannesburg SA
Got 1 engine from Toby and 1 new, sent both for repair and upgrade. Paid for upgrade to new engine in an effort to make it reliable! Paid for repair to other engine even though it had only a few hours of runtime.

6.Dean Groblaar - 6wren 160
Johannesburg SA
Sold 6 engines that failed and had to pay for repair, very negative responses from wren.

7.Jaco Strydom - 1wren 160 serial nr: 55280809
Sasolburg SA
Bought from Graham Dewaveren , failed after 4[SUP]th[/SUP] flight. Wren refuses to repair
According to records the engine received an ecu upgrade in 2009, witch the original owner paid for, within the first year because of flame-outs and inconsistent running. The engine then promptly failed on the 4[SUP]th[/SUP] flight. The engine was sent to wren for assessment. Now they state that no parts are available for repair!



8. Xantos - 1 wren 160 serial nr: 04080109
Bought a new turbine, it failed and was rebuilt by wren- 110310 and failed again

With due respects to Mr Dosu's different perspective to the whole Wren matter I would like to present some facts with regard to my experience with Wren.
I had one of the early Wren160s that shed a compressor blade .
Wren was good enough to replace the compressor wheel and rebuild the turbine in March 2012, I was still a little apprehensive about the repair and questioned Wren if they were sure that the replacement compressor wheel used in the rebuild was from a a new lot of compressor wheels.
The reply I got was most certainly unprofessional - Wren had NO record of the rebuild and therefore couldn't confirm whether the replaced component was indeed defect free. i.e. From the older lot of defective compressors or from a newer lot.
Two weeks ago the same rebuilt engine threw a blade again.
I have attached some pics from the latest incident.
Please bear in mind the engine was nowhere close to its service interval and thrust was limited to 112k RPM on the ECU
Wren of course has been gracious enough to request me to send the engine back.
The engine is back with Wren.
But the fact remains that Wren deliberately chose to ignore this matter and as a result I have a hole in my fuse and unnecessary damage sustained to the airframe.
One of the preceding posts refers to home repairs as a running/ticking time bomb
In my opinion how is Wren any better or more responsible?
Multiple reports of similar incidents with their 160 and the fact that they knew and accepted there was a problem with a component, should have initiated a recall.
Wren simply ignored the issue and wished the problem would disappear and in the process have simply endangered people’s safety.
So regardless whether the company is a handful of engineers with fantastic ideas or simply a Mom and Pop operation it certainly isn't acceptable to ignore the risk and the potential for damage
Any responsible manufacturer would have be expected to recall product that may have been released to the market with defective components.

9. Bigbri - 1 wren 160
Wren replaced the compressor and it failed later

10. NZJET - 1 Wren 160 serial nr: 031010
New Zealand
Wren 160 keeps exploding
He’s not the only one with a wren that keeps exploding..
I have had 2 wren 160’s the first I cannot tell you the SN of, lasted around 1 hour when the compressor failed destroying the entire engine.
Ron from wren replaced this motor with a brand new one, sn 031010 this motor had the new machined compressor design.

This turbine failed after around 4 hours. I believe the turbine wheel lost a blade. Wren would not repair any more but sold me parts to repair myself, which I paid $900 usd for but then they couldn’t sell me a turbine wheel so the engine sits as a paper
weight.

This is more about how crap the 160 is and the fact we have to keep paying to fix a engine that shouldn’t keep exploding. The story on my engine is the first one destroyed itself after 5 or so hours, ron replaced it with a new one which to went bang after 2 hours, sold me replacement parts for it (around 1k i think) and now i cant get a turbine wheel for it so its sitting as a door stop, i guess where it will stay!

11. Assimat - 1 Wren 160
Wren 160- 1 failure

12. Chatty c-makhija –6 Wren 160
India
All of the 160’s failed
Hello Jaco,

We had 6 wren 160s here in India, every single one of them failed. This was back in 2010 and wren repaired mine FOC for me. Unfortunately my friend was not so lucky and got a big bill from wren for the repair. After the upgrade I sold my 160 and the new owner had a crash due to different reasons.
Please let me know if I can be of any help.

Best regards
Chatty.
Failed out of warranty and repaired free of charge- Mike Murphy admitted it to be a manufacturing problem

13. In the haze -3 Wren 160
Idiot # 3. ( that is what he calls himself)
Cape Town SA
3 failed engines
Indeed, we have 3 160's that are lying in pieces with broken compressor wheels, too expensive to send back for repair.........



14. Jim Cattanach –1 Wren 160
Wren repairs out of warranty engine
I had a Wren 160 that destroyed itself in the air. It didn't have many hours on it, but was out of warranty. I sent it back to Wren.
Wren said it was too badly damaged to repair & sent me a new one, free of charge.
I thought the service I received was very professional.

Hi Jaco, I had a lot of problems dealing with Wren on previous occasions prior to the one where my 160 blew up. I decided, after getting nowhere with them, the only chance to get a satisfactory outcome, was to go public on RCU.
My case created quite a lot of negative interest for Wren & in the end, they gave me a brand new 160 free of charge, after admitting liability.
I would certainly be annoyed with the service you got & if a satisfactory solution was not forthcoming, would go on RCU & describe what happened & how you were treated.
Mentioning other cases of a similar nature, like mine, may help. They hate bad publicity.
I no longer have any Wren turbines & have no intention of dealing with them again.

Good luck
Jim


15. Phillip- 2 Wren 160
Damages his Viper when engine failed on take-off. Sent both in for repair and upgrade.

Still waiting to hear from wren.
Jacojet maybe you should let us know if you bought the engine new or second hand
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Old 02-25-2014, 11:40 AM
  #23  
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I don't think it matters in this case. Is every account of a broken 160 comp wheel blade attributable to a used motor? I don't think this sort of failure can be attributed to wear or length of service.

Last edited by CRX Turbines; 02-25-2014 at 11:43 AM.
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Old 02-25-2014, 11:42 AM
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Secondhand from original owner with 5 hrs and 20 min run-time.
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Old 02-25-2014, 11:57 AM
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And where you not told that there there could be a chance that it could blow up and to send it back to Wren before you run it.
I know of a couple that have 17 and 22 h on them with the upgraded compressors and no issues what so ever
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