dond
New Member
Joined: February 2014
Posts: 8
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Post by dond on Mar 2, 2014 21:43:46 GMT -5
Thanks for posting the info on the external fuel supply system. That should come in very handy. I don't think the corrosion is really that bad in the gearbox, perhaps the photos make it look worse than what it is, but it appears to be mostly surface corrosion and there's nothing affecting the bearing and seal areas that I've found (yet). Also appreciate the info on those being standard bearing and seal sizes Motion Industries or similar should have those in stock. I haven't pulled the rear bearing yet, I'm curious as to how it's configured. Thanks for the info on the corrosion preventative/treatment measures too. I'm *guessing* that this is anodized aluminum, sometimes hard to tell the difference though. I'd be inclined to agree that this gearbox was probably drained before storage and filled with *nothing*.
Here's a question I forgot to ask; how exactly do I mount/secure this engine to a frame for operation? It's got a metal band around it, but I'm not sure if that's just there for lifting, or if that's the method of attaching it what ever it's propelling?
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Post by finiteparts on Mar 3, 2014 20:47:57 GMT -5
I think the idea is to interface with the forward outer lip of the compressor inlet. On my engines, I have holes in the outer forward lip of the compressor housing and a large "clamping" ring near the aft end of the engine. I have some 3/8" sheet that I was going to plasma cut to fit the engine inlet inside, drill and bolt through the existing holes and then weld a box beam structure around to act as the forward mount. Then the aft ring would bolt to some box tubing that forms a lower frame. I'll try to draw it up when I get some free time...I still need to do some calcs on it to make sure that there is a margin of safety on the bending moments imposed by the full thrust capability...it should be relatively simple because in the grand scheme of things, 1000 lbf thrust is not that much...remember, a 1/4-20 bolt can support almost 1800 lbf...so a big pile of welded up steel should be almost overkill!
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duncan
Junior Member
Joined: December 2014
Posts: 68
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Post by duncan on Dec 26, 2014 23:38:32 GMT -5
Hello all of you turbine heads! I found the 'J44' posts & this board so I though I would join-in! I too own a J44-R-24 (Circa 1955) that I just got running in November & I am interested in learning more about these mysterious cold war era engines! I had help from a buddy fabricating an aluminum stand to hold the engine, fuel cell & batteries. I built a separate control console to operate the engine without having to be close to it. I bought an electric starter for mine, as not to have to mess with the compressed air. All of the electrical is 24/28 volts DC. I also built a 28 V charger to charge the batteries, using a power supply I bought off of eBay. I do plan to post some video of this project on You Tube when I get the editing done... more to come.
UPDATE (October 30, 2019): I have started a 'new' thread for my J44 project under the 'new' "Projects & Ideas" section here on JATO! Also, I have uploaded photos (old & new) directly to JATO blog pages. The engine is restored & running once again, so please check out my videos on my You Tube channel, "Darren Duncan".
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Post by finiteparts on Dec 28, 2014 15:22:43 GMT -5
Hi duncan,
I look forward to seeing your video. I need to get mine running...I was going to use it to blow the snow off the driveway! Ha!
~ Chris
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duncan
Junior Member
Joined: December 2014
Posts: 68
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Post by duncan on Jan 1, 2015 12:40:06 GMT -5
Hi everyone & Happy New Year! I have uploaded my J44 Project album to Photobucket. I will post a few here on the JATO board & give a link to the album itself. It shows the story from the day I picked the engine up through to the 3rd start/run. Enjoy. Album "The J-44 Project" links: s1058.photobucket.com/user/Darren_Duncan/The%20Fairchild%20J-44%20Project/story
UPDATE (October 30, 2019): I have started a 'new' thread for my J44 project under the 'new' "Projects & Ideas" section here on JATO! Also, I have uploaded photos (old & new) directly to JATO blog pages. The engine is restored & running once again, so please check out my videos on my You Tube channel, "Darren Duncan".
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duncan
Junior Member
Joined: December 2014
Posts: 68
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Post by duncan on Jan 1, 2015 14:22:02 GMT -5
SUMMARY <So Far>:
Since I have no prior experience with gas turbine engines & the J44 in particular, this project has been one of reading, trial & error, failures & successes! I have a nice copy of the USAF manual covering the J44-R-3, and I also have one of those old orange tech school manuals I got from Essco Aircraft (On Ebay), which covers the J44-R-24, which is my model. According to the manuals, the R-3 uses a more sophisticated fuel control system while the R-24 uses a simpler design. My R-24 is 'in between' that shown in the 'orange' manual & the R-3. My engine has an 'Acceleration Limiter Valve Assembly' in line between the governor fuel control outlet & the fuel cutoff valve. The R-3 also has a limiter valve, along with the servo control fuel system. The Accel Limiter's purpose is to limit overtemping & compressor stall due to too much fuel at once. It measures compressor inlet, outlet, & fuel pressures, then adjusts the maximum fuel flow to safe limits.
Overall, my main concern was the fuel control system & its operation. The previous owner said, "It runs." & I did find the filter container & lines to be clean, with no gunk or worse yet, corrosion! I wasn't sure if it would even start & then if it wouldn't just speed up out of control. Well, it starts & accelerates right up to idle at about 31-32% RPM so that part seems OK.
The next concern was that the lube system is/is not working. I ensured that the lines were clear & even pressurized the system with compressed air (less than 30 PSI!), which produced the 'oil mist'. After that test, I had excess oil running out of both bearings. I checked the front frame & inside of the jet pipe, at the rear bearing support, for oil puddling/running, after each run & found oil running/puddling (not a large amount, just a 'wet' area). This indicates the system is working & supplying oil! Looks good here.
Starting her was the next challenge. I tried with straight K-1 but got no light-off; just fuel spraying & blowing out of the exhaust. After 2 tries like this, I contacted the previous owner, who has had several of these engines. He said "These J44s are hard to start & generally won't, using just K-1 or even Jet A. You need to add some gasoline to the mix! About 20-30%. That should do it." Well, I mixed about 2.5 gallons of gas into my 8 gallons of K-1 already in the fuel cell, then purged the fuel system up to the fuel manifold. That did the trick! It lit-off with a 'Poof'! I killed it a couple of seconds later due to the fact that I didn't have any help with spotting & fire extinguisher manning. A second start try fired right off also, so I felt it was ready for a test run.
With a couple of friends to assist me, we rolled it out into my driveway on another day & made the first full start & run! It quickly came up to idle, with my hand nervously on that Emergency stop button, then stabilized at about 31% RPM. What a rush! You can 'feel' that power there, albeit a small & old school engine. With a consumption rate of 1.65 lb./hr./lb. thrust, is IS NOT an economical engine to run! Yes it does drink some fuel! About 0.75 gallons per minute at idle! My 15 gallon fuel cell should run about 20 minutes at that setting & only about 3 - 4 minutes at full power! The used fuel boost pump I bought on eBay will not flow enough to run the engine above 50% RPM, which is fine for a start. I will replace the pump (28 V, mounted on the stand down next to the fuel cell) when other bugs are worked out & I can afford it. I get 25 PSI with the fuel cutoff valve closed & it drops to about 15-20 at idle. Accelerating to 40% causes a drop to less that 10 pounds, so not much left.
On the first run, upon observing the tail pipe view of the engine, I discovered some erosion of the turbine nozzle blades around the '8 to 10 o'clock position', where I could see fire visible through it. Upon closer examination using a flashlight on a cool engine, I can see the some deterioration of several of the nozzle (stator) blades. This will require removal of the rear end & turbine wheel, to access the nozzle assembly. I am hoping my buddy can weld it up because these aren't around anymore! I don't think it is safe to run it up over idle with this damage; actually it really should not be ran at all! There is a chance that a blade could break-off & damage the turbine rotor! This would be a good time to have the turbine inspected for cracks or other signs of stress, as well as replace the rear bearing if needed. I will try to get this done before Spring, God willing.
In conclusion, I have taken almost a year since buying the engine in November of 2013, to get it running. That was a great feeling of accomplishment to reach that point! Half of the 'fun' is just the engineering, building, wiring, plumbing, troubleshooting, changing & getting it to run! Running it & sharing that experience with friends is the other half. I could have just patched it together some simple switches & wires but I wanted to make a cleaner look, so I just spent more money & bought some nice hardware! I have to buy a new computer so I can edit & process my videos! This old system (from 2006, Windows XP) just chokes on these HD video files! I will upload them to You Tube as soon as I can. I hope my experience can benefit some of you out there in gas turbine engine/J44 world! Also, I hope to learn more about them from you as well. Take Care & Cheers!
Darren Duncan
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rythmnbls
Veteran Member
Joined: August 2011
Posts: 145
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Post by rythmnbls on Jan 4, 2015 8:39:08 GMT -5
Congrats on your first run, there is nothing quite like standing near a turbine as it spools up to idle, it gives me goosebumps every time.
Looking forward to your videos.
Regards,
Steve.
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duncan
Junior Member
Joined: December 2014
Posts: 68
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Post by duncan on Mar 4, 2015 0:19:19 GMT -5
UPDATE (October 30, 2019): I have started a 'new' thread for my J44 project under the 'new' "Projects & Ideas" section here on JATO! Also, I have uploaded photos (old & new) directly to JATO blog pages. The engine is restored & running once again, so please check out my videos on my You Tube channel, "Darren Duncan".
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Post by Johansson on Mar 4, 2015 8:59:23 GMT -5
Good job! A sweet running engine for sure!
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Post by racket on Mar 4, 2015 16:10:01 GMT -5
Nice neat setup :-)
Cheers John
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duncan
Junior Member
Joined: December 2014
Posts: 68
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Post by duncan on Oct 28, 2019 8:33:31 GMT -5
October, 2019 UPDATE!
Major apologies for not updating my posts as the Project progressed, but I am officially declaring the J44 is now back together & running, after a major restoration! I was able to obtain a 'parts engine' (a J44-R-20) that apparently did not have many hours of use on it, with the major hot parts in excellent condition, to replaced my roached-out turbine stator & rotor. I had everything glass bead blasted & some parts powder coated, as well as some hard work on the cowling, which is stainless steel! Everything except the turbine, stator & combustor is the original J44-R-24 stuff.
I have uploaded/posted 2 'new' videos (May, 2019) of the engine starting & running after the restoration, on my You Tube channel, "Darren Duncan". Please go check them out, as well as my older videos, which cover the whole project from the beginning, 5+ years ago! There is a good bit of boring, dry, gearhead material you may wish to fast forward through, however. If you are a novice in gas turbines, as am I, then you may learn something from my experiences, especially if you are working on a Fairchild J44!
I will try to post some pictures on this blog, as soon as I can. Thanks for everyone's interest!
Cheers, Darren
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Post by stoffe64 on Oct 28, 2019 8:46:27 GMT -5
I have followed your restoration of this engine, very interesting!!
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duncan
Junior Member
Joined: December 2014
Posts: 68
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Post by duncan on Oct 28, 2019 8:56:39 GMT -5
Thank you! Much appreciated!
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duncan
Junior Member
Joined: December 2014
Posts: 68
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Post by duncan on Oct 28, 2019 9:43:34 GMT -5
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BFTO
Veteran Member
Joined: February 2016
Posts: 128
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Post by BFTO on Oct 28, 2019 9:58:55 GMT -5
I have followed you since the beginning, nice work! what a beautiful engine!
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