Go Back  RCU Forums > RC Airplanes > RC Jets
Reload this Page >

Unblocking injectors?

Notices
RC Jets Discuss RC jets in this forum plus rc turbines and ducted fan power systems

Unblocking injectors?

Old 09-19-2014, 02:06 PM
  #1  
DominicM
Thread Starter
 
DominicM's Avatar
 
Join Date: Nov 2002
Location: Hampshire, , UNITED KINGDOM
Posts: 2,069
Received 37 Likes on 29 Posts
Default Unblocking injectors?

Have got a GBooster 160 that has had its injectors block up only 5 starts after it came back from a service at EvoJet. Definitely blocked as the initial flame is poor and compressed air does not flow though the fuel port. Wanted to know if there is anything I could flush through the port into the injectors to clear what I am told is probably carbon build up? Any help appreciated. I'm loathed to send it to IQHammer unless I need really need to. EvoJet won't return my emails. Got me labelled as a difficult customer I guess. Go figure.
Old 09-19-2014, 02:34 PM
  #2  
Vettster
 
Vettster's Avatar
 
Join Date: Sep 2007
Location: Beeton, Ontario, CANADA
Posts: 1,337
Likes: 0
Received 5 Likes on 4 Posts
Default

Well im no expert.. but i did do the same thing on a RAM 750 a couple of years ago. I submerged the ring in Acetone for an hour and then swished it around. Then blew it out with low air pressure. I then hooked up a propane bottle to it and with very low!! pressure lit all the wicks to check for consistency. They all burned perfectly even so I re installed it.

Cheers
Old 09-19-2014, 04:47 PM
  #3  
rcpete347
My Feedback: (251)
 
rcpete347's Avatar
 
Join Date: Jan 2002
Location: Bolton, ON, CANADA
Posts: 2,460
Likes: 0
Received 1 Like on 1 Post
Default

HI, their is useually a restrictior near the discharge end, about 7thou dia.. You must dissassemble the turbine to get at the end of the sticks and gently free the sticks from carbon with a 5thou wire.I think at time you have nothing to loose anyway.
Rcpete
Old 09-19-2014, 11:22 PM
  #4  
DominicM
Thread Starter
 
DominicM's Avatar
 
Join Date: Nov 2002
Location: Hampshire, , UNITED KINGDOM
Posts: 2,069
Received 37 Likes on 29 Posts
Default

Thanks both. I was apprehensive of doing anything but I'll have a go. Cheers.
Old 09-19-2014, 11:28 PM
  #5  
bluescoobydoo
 
Join Date: Dec 2006
Location: harwich, UNITED KINGDOM
Posts: 709
Likes: 0
Received 0 Likes on 0 Posts
Default

if you know anyone who works in a lab see if the have access to a ultrasonic cleaning bath a few hours in it with a cleaning solution should clear it
Old 09-20-2014, 01:07 AM
  #6  
DominicM
Thread Starter
 
DominicM's Avatar
 
Join Date: Nov 2002
Location: Hampshire, , UNITED KINGDOM
Posts: 2,069
Received 37 Likes on 29 Posts
Default

How do I remove this to get to the injectors?
Attached Thumbnails Click image for larger version

Name:	image.jpg
Views:	267
Size:	1.08 MB
ID:	2033638  
Old 09-20-2014, 01:33 AM
  #7  
Jgwright
 
Join Date: Jul 2006
Location: Norfolk , UNITED KINGDOM
Posts: 1,409
Likes: 0
Received 0 Likes on 0 Posts
Default

Dominc

You will have to strip the engine down completely.

This is not that straightforward with the G booster, as I found out, has several soldered joints that have to be unsoldered to get the thing apart. (there is an internal thermocouple and the internal Kero plug.) Even the front cover is not straightforward to remove and you will need to take many photos to make sure you reassemble it all in the same way. If I was you I would not attempt it but try and find someone who has doe a strip down on a Booster before and persuade them to do it. The engine will definitely need balancing on reassembly. In my view this engine was not designed to be easily serviced.

The injector needles are fixed to the rear of the diffuser like the Jetcat engines.

If you attempt to do this then you need to start at the front end.

John
Old 09-20-2014, 01:45 AM
  #8  
DominicM
Thread Starter
 
DominicM's Avatar
 
Join Date: Nov 2002
Location: Hampshire, , UNITED KINGDOM
Posts: 2,069
Received 37 Likes on 29 Posts
Default

Suspected as much. Thanks John. I'll send to IQHammer.
Old 09-20-2014, 04:39 AM
  #9  
erbroens
 
erbroens's Avatar
 
Join Date: Nov 2003
Location: Curitiba, Parana, BRAZIL
Posts: 4,289
Likes: 0
Received 14 Likes on 11 Posts
Default

Here in Brazil, some years ago we didnīt have local servicing..and sending back the turbine for repairs to the usa was a adventure.

At that time we had a brand new airplane here in wich my then inexperienced friend forgot to install the fuel filter and his Jetcat P120 ended up clogged.

After some considerations we decided to use a syringe with a 4mm tube installed in the turbine fuel intake to remove all the fuel it had inside. Then we saw dirt particles with the fuel inside the syringe and the problem was solved, without even taking out the engine off the plane..

I think it is worth to give this a try.

Last edited by erbroens; 09-20-2014 at 04:42 AM.
Old 09-20-2014, 09:23 AM
  #10  
GhostRider 1
 
Join Date: Feb 2013
Location: Lost Wages, NV
Posts: 85
Likes: 0
Received 0 Likes on 0 Posts
Default

Go online and look up Carbon-X. Buy a gallon of it, pour it in a plastic container and soak the bottom half of the turbine in it for 15-20 minutes. Blow compressed air through the fuel port and it should clear it out. You can also use automotive brake cleaner to try and clear the injectors. If you use brake cleaner, make sure you leave the turbine out and pump your fuel through it to re lubricate the bearings as the brake cleaner will strip all the fuel and oil out of the turbine. The internals are Inconel or stainless and the brake cleaner won't hurt anything inside but give it a good cleaning. Hope that helps..
Old 09-20-2014, 11:41 AM
  #11  
Justflying1
 
Join Date: Apr 2011
Location: Melbourne, AUSTRALIA
Posts: 860
Likes: 0
Received 1 Like on 1 Post
Default

Originally Posted by GhostRider 1
Go online and look up Carbon-X. Buy a gallon of it, pour it in a plastic container and soak the bottom half of the turbine in it for 15-20 minutes. Blow compressed air through the fuel port and it should clear it out. You can also use automotive brake cleaner to try and clear the injectors. If you use brake cleaner, make sure you leave the turbine out and pump your fuel through it to re lubricate the bearings as the brake cleaner will strip all the fuel and oil out of the turbine. The internals are Inconel or stainless and the brake cleaner won't hurt anything inside but give it a good cleaning. Hope that helps..
DO NOT DO THIS.
I have never pulled a turbine apart but I'm mechanically minded and this idea could make things wears. The fuel ports from a turbine are very small from what I read and have seen from a gentleman who was from Western Australia who was kind to pull one apart and run things thorough with me. If you have dirt stuck inside pressurised air could push the dirt in further making it even harder to remove. Air pressure could potentially also damage the fuel port. If I where you I would send this in to an authorised professional to do however if I just could not afford to do this or it was not practical I first would try the syringe idea and if this would not work I would pull it all apart insert the fuel ring in clean Jet fuel and on very low pressure if possible to do would blow air from the outlet back through.
Again I stress that the best option is to take it to a professional.
Ivan
Old 09-20-2014, 08:30 PM
  #12  
GhostRider 1
 
Join Date: Feb 2013
Location: Lost Wages, NV
Posts: 85
Likes: 0
Received 0 Likes on 0 Posts
Default

Ivan,

Carbon -X is used by all the full scale jet engine repair facilities and works fantastic. I have a friend that work in the scale turbine industry and he is the guy that turned me onto it. It virtually dissolves all carbon and grime deposits and I'm sure it will clear the clogged injectors in his turbine. How is air pressure going to damage the fuel injectors, they are made out of stainless steel or Inconel and designed to be under pressure. Automotive Brake cleaner is design to break up and dissolve any dirt or grime deposits on contact. If I was a gambling man, I would guess his injectors are only clogged with fuel sediment and the brake cleaner will do the job by itself. I am interested to know what turbine you saw get taken apart? If it is so weak and fragile that some compressed air can ruin it, I want to make sure not to buy that turbine!!

Also, what you are suggesting to use a syringe to try and clean the injectors will require a complete tear down of the turbine and that means it will need to be re balanced when assembled. Dominick was trying to clean it without sending it back to EVO after they failed to fix it the first time. My suggestion WILL work and save him the agony of sending it back again.


Ghostrider 1 out!!
Old 09-22-2014, 03:52 AM
  #13  
basimpsn
My Feedback: (5)
 
Join Date: Dec 2001
Location: Mia, FL
Posts: 2,580
Received 4 Likes on 4 Posts
Default

Don't try to remove the nut from the turbine. remove the case first and take another picture to see your burner setup. By the way I just reassemble a old RAM turbine yesterday
Attached Thumbnails Click image for larger version

Name:	Screenshot_2014-05-13-11-11-18.png
Views:	125
Size:	748.3 KB
ID:	2034111   Click image for larger version

Name:	Screenshot_2014-05-13-11-12-38.png
Views:	137
Size:	784.3 KB
ID:	2034112   Click image for larger version

Name:	Screenshot_2014-05-13-11-11-02.png
Views:	119
Size:	788.6 KB
ID:	2034113   Click image for larger version

Name:	Screenshot_2014-05-13-11-12-22.png
Views:	125
Size:	1,011.0 KB
ID:	2034114   Click image for larger version

Name:	2014-09-22 08.25.49.png
Views:	154
Size:	1.08 MB
ID:	2034119   Click image for larger version

Name:	image.jpg
Views:	102
Size:	789.5 KB
ID:	2034120   Click image for larger version

Name:	2014-09-22 08.26.40.png
Views:	100
Size:	371.9 KB
ID:	2034121  

Last edited by basimpsn; 09-22-2014 at 04:35 AM.
Old 09-22-2014, 10:06 AM
  #14  
Henke Torphammar
 
Henke Torphammar's Avatar
 
Join Date: Oct 2002
Location: Ljungby, SWEDEN
Posts: 1,981
Received 7 Likes on 7 Posts
Default

Mechanical cleaning is probably the only way.

But if trying to dissolve the dirt I would soak the engine in the preferred cleaner and then use a fuel pump with filter to suck through the fuel port. It's pretty obvious if you got something in that stuck half way through it will be the only way to pull it out, not push it further in(!)

You need to remove some electronics first and as John stated it might be a difficult task on some engines.

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.