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gofastclint

Subaru Boxer Diesel.

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I bought a new Hyundia i30 turbo diesel at the end of July, leased through work as a salary sacrifice actually. It replaces the 2.5L petrol subaru forester I had for 8 years since new.

 

The 2.5L petrol forester towed the trike ok at 100km/h and fuel economy would change from 8L/100km to 12 or 13L/100km. Any headwinds would drop its speed to 90km/h unless I got behind a big truck.

 

I've yet to tow anything with the i30 except my pushbike on its rack. Fuel usage for just the car is 5L/100km at 110km/h. The i30 weighs the same as my 2002 forester did due to the heavier deisel engine and pulls better up hills in 5th gear than the forester did, so I'm hopeful about how well it will tow a trike. I'm keeping in mind that it's "only" a 1.6L turbo diesel, so I bought a "Scan Guage" for $200 so I can watch how much the engine is working or suffering at any given moment and hopefully avoid blowing it up.

 

Cheers,

 

Glen

 

 

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Just so happins i've obtained a soob diesel engine, brand spanker..........yet to arrive here tho.

 

Cost.................$18k plus fees etc etc. 2L turboed, best power/torque around 2000.............2500. Planning on running a direct drive constant speed prop. "Fitting" may be a pain, turbo etc is all underside of the block............the main concern ...............is weight, they are bleedin heavy, my man tells me, more than an EJ25 soob.

 

You never know, maybe Rotax will release diesel 914's...........now that would be nice.

 

 

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How do the new diesels go for vibration and how does the fuel go at low temps without waxing and not flowing at or below zero degrees?

Brian

Modern Diesels with counter balancing, are smooth.They are very petrol like these days, some cars you wouldnt know they were diesels.As per fuel waxing, i cant answer that question.

 

I will go out on a limb here- i think Diesel a/c engines will be the future as well as electric,.Petrol (not avgas) a/c engines will be electronic ignition, like Lycomings new version, their testing at the moment in their Big Blocks.

 

 

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Diesel Waxing

 

How do the new diesels go for vibration and how does the fuel go at low temps without waxing and not flowing at or below zero degrees?

Brian

Hi Brian,

 

 

Excellent question re Diesel Fuel Waxing …

 

 

In my view, Diesel Fuel will never be suitable for aviation use in its current formulation because of the risk of waxing.

 

 

Diesel fuel "Cloud Point" varies around Aust from state to state throughout the year … what works in one geography will not be suitable in another.

 

 

If you were to fill your tanks and fly south …. leave fuel in your tank from a warmer month and then use in a cold month … fly at an attitude that chills down the fuel in your tanks … you could end up with wax forming in the fuel lines or blocking filters.

 

 

As an example, over a 30 day period between say Gladstone and Brisbane there is as much as a 12deg C difference in Cloud Point by government regulation. If you were to fill in Gladstone and fly South to Bris 30 day later you could easily find you are operating beyond the safety parameters of the fuels temperature design limits.

 

 

On the other hand, Jet A1 makes a very good alternative to Diesel fuel as it is designed to operate over an extreme range of temperature and will happily run in a diesel engine application, that is, so long as the engine has been designed to use it.

 

 

Cheers

 

Jack

 

 

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An issue in this discussion if mixing reliability from old type diesels and that of new CRD turbos with ECU etc etc. They are very different and this is seen in automotive world

 

New designs are not reaching longevity of older designs. Much of the technology is applied to reduce emmissions. Weights and maint cosrts are well up compared to petrol models

 

Without cetrtified ECU you dont have backup system and you are reliant on battery power

 

Did someone infer AVTUR is more availiable than AVGAS in regional areas??? Nowhere I fly.

 

I dont think AVGAS wont dissapear for some time, it will just get dearer until at some point we stop buying it

 

My bet is that we will see "AVPULP" turn up, clean QA assured PULP which will replace it, and these extra features will mean higher price!!! So back where we are now but paying similar price for lower octane unleaded fuel which looses performance after a few weeks in the tank.

 

 

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Fuels

 

I dont think AVGAS wont dissapear for some time, it will just get dearer until at some point we stop buying it

 

My bet is that we will see "AVPULP" turn up, clean QA assured PULP which will replace it, and these extra features will mean higher price!!! So back where we are now but paying similar price for lower octane unleaded fuel which looses performance after a few weeks in the tank.

 

I don’t think we are at risk of Avgas being pulled for some time. There was a plan presented 3 weeks ago to the US EPA by the Industry Avgas Coalition to develop a programme called “FAST” (Future Avgas Strategy & Transitional Plan) to develop a viable “drop-in” fuel solution.

 

In terms of the near future … It’s reasonably clear we will see a lead reduction (may be 50%) on the current LL100 to move towards meeting the 2006 Friends of the Earth Petition to outlaw lead. It’s also clear that aviation engine designs will increasingly accept high octane zero lead fuel formulation to also reduce the lead demand.

 

In my view, there is still a heap of data needed to understand the impact of lead on society from avgas (notwithstanding the fact that lead is harmful) and a bunch of petrochemistry research to develop a suitable “drop-in” fuel product that will provide safety with engine durability at an affordable price.

 

Avgas will be around for a while yet!

 

Cheers

 

Jack

 

 

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Has anyone done any research on how the torque/power is deliered by a (turbo) diesel engine to a propeller, especially in direct drive applications.

 

It's just that in some other threads there have been problems mentioned with a certain direct drive aero engine when using certain composite props rather than the standard wooden prop. A diesel I would guess would deliver its torque in a rather pulsey fashion with its low revs and high compression ratio unless it has a very heavy flywheel.

 

Any thoughts?

 

 

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Has anyone done any research on how the torque/power is deliered by a (turbo) diesel engine to a propeller, especially in direct drive applications.It's just that in some other threads there have been problems mentioned with a certain direct drive aero engine when using certain composite props rather than the standard wooden prop. A diesel I would guess would deliver its torque in a rather pulsey fashion with its low revs and high compression ratio unless it has a very heavy flywheel.

 

Any thoughts?

That is one of the issues raised in relation to the Zoche radials I mentioned previously, they kept breaking props and it was theorised that the minute variation in rotational speed resulted in a load reversal several times per propellor revolution, which fatigued the prop material and led to the failures.

 

 

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prop vibration would not be an issue if we could get a 3 cyl inline 2 stroke diesel; there are some nice sized 4 strokes about for running cars, fire sprinklers, gensets etc. often run around 3,000 rpm. At my work the smoothest powerplant we had was a V16 Detroit (essentially 2x V8 in tandem) they do require a turbo to operate, and use conventional valvegear, most diesels use a turbo anyway. Is it just a green thing that prevents having a small 2 stroke diesel?

 

I've also been considering Avtur (Jet-A) as a kerosine fuel for spark ignition engines, small gensets and the old Fordson major tractors used to do this, at the moment the only likely engine for this is 75hp Austro rotary

 

Error

 

Ralph

 

 

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"Diesel's are good for what they are designed for Low reving high torque applications,"

I thaught that was one of the main design criteria of a good aircraft engine

 

Cheers Helmut.

011_clap.gif.c796ec930025ef6b94efb6b089d30b16.gif

 

 

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On 07/02/2009 at 5:09 PM, gofastclint said:

Subaru estimates that half of all its sales in 2010 will be diesel.

 

Crystal ball says "care to play again?"

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30 minutes ago, mnewbery said:

Crystal ball says "care to play again?"

The fact that subaru (I am a fan)  appeares to have dropped the diesel boxer will not stop some wanting to put one in an aircraft. I like my turbo diesel common rail dual cabs but there is no way i would want to fly one, the high pressure pump, suction control valve and injectors can give trouble. The fuel injection system on a petrol is simple and low pressure.  

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The latest petrol direct cylinder injection is not low pressure and is very precision. I don't now how they manage to lubricate it. (but it works). Nev

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On 16 September 2010 at 8:12 PM, jetboy said:

...I've also been considering Avtur (Jet-A) as a kerosine fuel for spark ignition engines, small gensets and the old Fordson major tractors used to do this, at the moment the only likely engine for this is 75hp Austro rotary...

Using jet fuel also interests me, Jetboy. I learned to drive on a grey Furgie, which started on standard petrol; after it warmed up we switched over to kero. Why can't our aero engines do that?

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Old K, the problem with poor quality fuels such as Kerosene is that they need to be pre-heated to enable reasonably efficient combustion.

But the "reasonably efficient" combustion of Kerosene is still rather poor, and the poor combustion characteristics of this fuel leads to excessive crankcase oil dilution - meaning short oil change periods to avoid the dilution of the oil by the unburnt combustion by-products, which leads to the oil losing its lubrication abilities, leading to engine bearing failure.

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38 minutes ago, Old Koreelah said:

Using jet fuel also interests me, Jetboy. I learned to drive on a grey Furgie, which started on standard petrol; after it warmed up we switched over to kero. Why can't our aero engines do that?

Many pilots have tried this, filling up with jet-A instead of avgas. They warm up, take off and then detonation destroys the engines.  The grey Ferguson has very low compression and power.

Edited by Thruster88
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Facthunter, the latest technology in injectors is DLC - Diamond-Like Carbon (Coating). This diamond-hard coating is used in most current fuel injectors, and it's especially durable, even with common-rail injector pressures that often reach 30,000psi (206MPa).

 

https://www.coating.com.au/dlc-coating-au/

Edited by onetrack
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The UK boaties had to have a cylinder head spacer, to convert to kero, as petrol went too expensive for boats.

I,ve still have the magazine pullout that shows "how to do it yourself ", on the outboard motors.

BUT

It didn,t last as the oil companies soon jacked up he price of kero & heating oil,

In NZ I had a car running on 80% ethanol & 20% petrol using a 1/8th copper plate spacer & two gaskets. (worked well, when  no one had fuel to wast on holidays ).

spacesailor

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6 hours ago, Thruster88 said:

The fact that subaru (I am a fan)  appeares to have dropped the diesel boxer will not stop some wanting to put one in an aircraft.

What about the terribly heavy weight and the crankshaft breakages then?

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40 minutes ago, bexrbetter said:

What about the terribly heavy weight and the crankshaft breakages then?

I must not have made my point clearly. I like subaru but not the diesel which should never ever be used in an aircraft. 

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I've got a perfectly good, low km, 2014 model, Subaru Boxer diesel in my workshop. It's done just 11,000kms. I acquired it from a flying-oriented gentleman, who had plans on fitting it to some sort of Recreational aircraft.

However, when I pointed out the major weight penalty of the Subaru Boxer diesel and the need to keep weight down with aircraft engines, he merely stated to me, "Oh, it'll work, it just has to be the right aircraft!"

Maybe he was just waiting for the 760kg RA weight increase? :scratching head:

 

I cannot see where the Subaru Boxer diesel makes a good light aircraft engine, it is simply just too heavy. I think they fixed the crankshaft breakages problem with them, because they only occurred for a couple of years around 2008-2010, and Subaru did some re-engineering on the crankshaft that fixed the problem. I am not privy to what the engineering changes were.

Edited by onetrack

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Despite the high initial cost this is a good option for the ultimate recreational aircraft engine.

 

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