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Subaru Diesel....

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PH-SCP

Well Known Member
Found this article on Automotive.......

Subaru develops horizontally opposed Turbo Diesel engine

September 29, 2006 Subaru Europe President Hiroyuki Ikeda dropped an unexpected announcement in his Paris motor show speech when he mentioned that the company was working on a SubaruBoxer Turbo Diesel and that development is nearly complete. The horizontally opposed engine layout made famous by Volkswagen has long been favoured by Subaru and has been the mainstay of its fleet for more than three decades with its latest effort winning first place in the 2.5-liter class of the International Engine of the Year Awards. Though it?s logical that the company would develop the world?s first horizontally opposed diesel engine, there are many technical difficulties to overcome, so it was by no means regarded as a given. Anyway, we have the drawings in high res and we suspect it?ll be a beauty.

The superb rotational balance of the horizontally-opposed engine allows low vibration because the pistons counteract each other to cancel it out. Moreover, with its firmly supported crankshaft, the crankcase construction is strong enough to resist huge combustion pressure. The horizontally-opposed engine?s character is proving an excellent match for a diesel engine.

Ikeda said, ?the adoption of a thin journal for the crankshaft and turbo charger placed under the cylinder block enhances all the advantages of the Boxer Engine, which are a low center of gravity, lowvibration, high rigidity and compactness.?

Ikeda said he anticipated unveiling the Subaru Boxer Turbo Diesel engine next year at Geneva Motor Show.


With all the expertise around, specially in the Eggenfellner-company, I wonder if this could be used in an RV-7....
For the European builder it would be a dream come true...... :) :)
Anyone with more information about power output etc. ??
 
Unless they are going to MMC blocks and heads, this will just be too heavy for RV7 though 9s. Might have some application for RV10s if the long block weight is under 350 lbs. Going to be a few more years before these show up in bone yards. The modern electronics on diesels are extremely complicated and interconnected with chassis electronics to a large degree. A real mess to transpose into an aircraft application unfortunately and make it work properly.
 
I wonder what the RPM range is going to be----------

The possibility of a direct drive instead of a PSRU is bouncing around in my poor brain.

Mike
 
PH-SCP said:
For the European builder it would be a dream come true...... :) :)
Click to expand...
I bet it will be close to that. However it's real dream come true when it works also inverted. I yet haven't catched diesel for a inverted flying and so far I think that the reason has been inside turbo. But this is a great alternative.
 
The direct drive turbo thing is a real possibility with turbo diesels. That will save a good 35 lbs. over a redrive. Add a bit more boost and it might be feasible.

The Clarke brothers have demonstrated the performance of gasoline, direct drive, turbo Sube motors for many years. While there is a weight penalty relative to engine size and power output, the simplicity of the the package without redrive not to mention cost, makes the concept attractive. With the turbo diesel generally having a much lower torque peak rpm than most gasoline engines, operation at some reasonable prop rpm is possible although Reg Clarke is generally operating at about 3500rpm I think so most MT, Hartzell prop would not be useable.

The turbo does not care if it is upside down as they usually have a scavenge pump in aircraft because they are mounted below the oil level.

I'm thinking about the new BMW335ci engine 300hp and 300 ft./lbs. at 1900 rpm. Makes about 160hp at 2800 rpm. That would sound sweet in a long nose RV. Have to mount it inverted to correct the thrust line and dry sump it. Minor problem. :rolleyes:
 
photo of sub diesel

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Love Subies, diesel! GREAT

I am glad to hear Subaru is getting a diesel and a Boxer at that! I might me in the market for that. That might be my next car. When ever looking at cars Subaru is on my look at list. My first nice practical car was a used 1982 Subaru 4 Dr GL I got after Grad from college. I drove that thing for 10-11 years and sorry I traded it in. The Hybrid does not turn me on but the diesel does. Almost as good or better mileage as a Hybrid. VW has always been hit and miss in quality and the Benz big bucks. I can't wait. Wounder if it will sound like a diesel, clack clack clack clack.

(UPDATE: No Cars for 2007 in North America, only Europe. :( , maybe 2008)
 
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Aerobatic Diesel

Martin Long at Wilksch Airmotive told me that thy would be fitting their 4-cylinder diesel engine with a dry sump "to make it aerobatic".

Dave
 
Dave_Boxall said:
Martin Long at Wilksch Airmotive told me that thy would be fitting their 4-cylinder diesel engine with a dry sump "to make it aerobatic".
Click to expand...
Thanks for the info. However I think that WAM-160 can be a little too small for aerobatics (especially for RV-7 or 8) as maximum continous power is rated 100 kW. I wouldn't like to play with 5 min max. TO powers. :(
 
I have owned an opertated well over 100 peices of diesel equipment and I have found that if you ever run one DRY it is a son-of-gun to restart. Given this problem I would NEVER put a diesel in an airplane until they prove to me it will restart like a gas engine.
I think anyone who runs a plane out of fuel in flight should loose the ticket for a period of time. Yes, I toooo have forgot to switch tanks, the most stupid mistake I have ever made. I was at altitude and nobody but me knew about it. Don't tell anybody that pilots forget to switch tanks....
 
I almost forgot, Diesels create a frequency vibration much different than a gasoline engine.
I will bet that many panels will crash and burn as a result of this harsh vibration. I have not considered how this will effect nuts and bolts?
 
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210TC said:
I have found that if you ever run one DRY it is a son-of-gun to restart.
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I have asked Mark Wilksch about this - he reckons it is down to design and configuration of the injection system. He says it isn't a problem on the WAM engines and that they will restart after inadvertent fuel starvation in a timely fashion - I can't remember how long he said it took, but it was definitely quick enough to put it in the non-issue basket - unlike the Thielerts, from what I have heard.

A
 
I will believe it when I see it.
Diesel injection requires apx 3000 plus psi (and UP) and if a small air bubble inters the system you have got problems, on the other hand the less efficient systems used on the old cummins and detroits supply fuel to the injector via a low psi pump and the injector becomes the pump. Cam lobe operates the rocker arm which pushes the plunger down in the injector and presto vaporised fuel, just like the intake and exhaust valves work. This is the choice system for restart.
If they make a system like this with a fuel supply line to the injector AND add a full flow return line to the tank I will take a big LOOK. The return would allow bubbles to exit the system with ease. The Germans have used return flow for many years and all have copied, automotive only. Both engine's mentioned have return system's that could use a small amount of improvement.
 
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I appreciate that you remain to be convinced, but I don't think you need to teach Mark or a lot of people involved in these diesel engines how they work.

I was interested to know how this issue was dealt with so I asked Mark - I'm sure that he wasn't bull****ting when he answered me.

FWIW, the WAM diesel combustion/injection system is 'closely related' to german automotive IDI technology

A.
 
Wilksch Restart

I'm installing a Wilksch (we cast the bottom cowl this weekend). The procedure for starting a brand new engine is to turn on the electric pump, wait for a short while then a few seconds on the glow plugs before hitting the starter. There's no bleeding the fuel system or any other funny business - and the engine will self-prime if no electric fuel pump is fitted.

I guess a restart after running the engine dry can't be any worse than that.

The Wilksch has a fuel return line all the way back to the tank.

Dave
 
rv6ejguy said:
Unless they are going to MMC blocks and heads, this will just be too heavy for RV7 though 9s. Might have some application for RV10s if the long block weight is under 350 lbs. Going to be a few more years before these show up in bone yards. The modern electronics on diesels are extremely complicated and interconnected with chassis electronics to a large degree. A real mess to transpose into an aircraft application unfortunately and make it work properly.
Click to expand...

Hi,
i have one unit in my garage here in TN.

The long block weigh less than 300lbs :eek:

http://www.vanorama.com/

GSB
 
I want one!

Syncrogreg said:
Hi,
i have one unit in my garage here in TN.

The long block weigh less than 300lbs :eek:

http://www.vanorama.com/

GSB
Click to expand...

How did you get it?? I've been trying to get one for quite some time.

On another subject, earlier in this thread, there is some concern expressed about a diesel's ability to re-start after an in-flight shut down.

Last year, I inadvertently ran my Wilksch WAM 120 out of fuel on one tank while cruising at about 7500'. Scared the heck out of me, but once I determined that I had run one tank dry, I simply switched tanks. Before I got my hand off the selector, the engine was running perfectly, no sputtering, missing, nothing. In less than 3 seconds, it was as if it had never shut off. Kerry from WAM had told me early on to just try that some time, and that I would be amazed at how quickly it re-started. I was!

Back to the Subaru: please let me know how I can get one, I'm really interested in seeing how it would do in a plane. It is lighter than I thought it would be, but still heavy, once you add in a cooling system and gearbox. I'm sure some parts can be lightened to make it a viable aircraft engine.

Kurt
RV9 / WAM 120 diesel, 209 hours
 
210TC said:
I have owned an opertated well over 100 peices of diesel equipment and I have found that if you ever run one DRY it is a son-of-gun to restart. Given this problem I would NEVER put a diesel in an airplane until they prove to me it will restart like a gas engine.
I think anyone who runs a plane out of fuel in flight should loose the ticket for a period of time. Yes, I toooo have forgot to switch tanks, the most stupid mistake I have ever made. I was at altitude and nobody but me knew about it. Don't tell anybody that pilots forget to switch tanks....
Click to expand...

You're correct about it restarting. If you run a tank dry in a gasser, you just switch tanks. A diesel however because of the setup of the fuel system the injectors have to be bled. The fuel atomization is incumbent on pressure. If there is any air in their you're pretty much screwed. Like anything else in aviation, don't screw it away.

Never mind, just read page two and you know all this.
 
Diesel restarts

Most if not all modern automotive diesels use the Common Rail type of injection system. This has a "Rail" which is basically a pressurized pipe where the fuel recirculates and the injectors are fed from this rail. Since the fuel recirculate any air that gets into the system is purged. If the system is run dry, not recommended as the pump is also dry, when the tank is switched the pump will pick up fuel very similarly to a gasoline system and will purge any air.

The older style Bosch systems that may still be used on some small diesels that do not have to meet emission requirements do have to be manually purged to get them running again, and definitely would not be recommended for aircraft use.

I wonder what the marine people did as they had the Bosch injection systems and running a boat motor out of fuel could be just as dire as an airplane.

BP
 
Diesel restart

My Wilksch diesel has the old-style, lower pressure fuel system, of WAM's own design - not a high pressure common rail system.

As I mentioned above, in post #17, when run dry, it restarts IMMEDIATELY. The injection pump was designed for Jet A, so it is lubricated with engine oil. It's not such a big deal to run it dry.

We did some testing years ago with our Cessna 180 with Cont. 0-470 gasser, to defend ourselves in a lawsuit. We ran it dry many times (unported the selected tank) to see how long it would take to restart, and sometimes it would take up to 2 1/2 minutes before sputtering back to life. Believe me, that 2 1/2 minutes seemed like an hour....

I'll take the diesel any day!

Kurt
RV9, WAM 120 diesel, 210 hours
 
Subaru Diesel Engine Revisited

Has anyone done any serious work on an aircraft fit as yet? For example: PSRU or direct drive with torsional vibration damping, ECU re-mapping, remodelled air intake and manifold (possibly in carbon fibre), dry sump conversion, exhaust re routing, radiator / inter-cooler repositioning and reduction in size for greater airflow. I read that someone was looking at the Rans to fit the engine. boxeer.com has been writing in rotaryforum.com and would suggest some awakening if interest in this engine. I would be interested to know

Steve.
 
Hi. Yes we have the boxeer plane that is underconstruction. It based on Osprey GP-4 . All the modification stated above are being done. A kit engine+ecu is now availlable for 10k. It. Is a turn key solution it does not include the mods on the engine.

The complete firewall package will be for sale after heavy duty experimentation.

Www.boxeer.com

Greg
 
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