# Light weight diesel auto conversion

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#### Tom DM

##### Well-Known Member
Supporting Member
HI...
I got one,
a WAM 120, quite new less than 20 hours on the ground.

I may be interested by selling it!

anybody?

Well well, then you are the first private person outside UK and US I "know" -even if it is through a forum- who bought one.
For which airplane was it intended? Which production number?

Saw your avatar and know Candillargues quite well. Nice hangars, lots of builders there, the fire-combating airplanes and the anti-mosquito-brigade with the choppers. Take off over Etang d'Or often watched by flamingos.

We had several summer flying camps, based at Courbessac (Nimes) and so LFNG or Aerodrome de Camargues was often visited. First solo's were celebrated with a glass of champagne and while the "victim" was savouring it, with a bucket of water. After several muggings at Courbessac the flying camp moved for one year to Candillargues but it did not continue as camping became banned on the facility. Maybe our reputation of long nights parties was a factor: in those 10-14 days period we flew extensively by day and partied all night. We used to invited half of the nearby village, the other half showed up regardless. Is the pizza-guy at the entree of the airfield still around? He opened up especially when "les Belges" flew in.

12 years back already: Time flies a turbo-prop. I encountered a moment of insanity there after betting : biking from Courbessac via Lunel to Cardillarques and then onto Montpellier. Never had my butt hurting so much. The bike still resides in Montpellier as I begged / hitched and obtained a plane ride back. I think even I haven't ridden a bike since.

Sorry, my interests in the WAM-120 are academical but if you still have contacts there: please to look around for an O-200 loonley on a shelf or for some-one interested in a semi-free, flyable Jodel D113 (but missing its engine)

#### KeithO

##### Well-Known Member
Running new common rail engines on Jet A is no small matter. Diesel no problem. Adding a 2 stroke lubricant may address lubricity, but the viscosity issue will remain. And was we know, jet A is plenty volatile enough to ignite in a crash. Thus, for local flights it is no problem to have a caddy with enough diesel on hand. But on a cross country, the number of airports with diesel availability is near zero.

#### Tom DM

##### Well-Known Member
Supporting Member
Trains/tracks in Europe are mainly for passengers and owned by the goverments.
French goverment for example has invested an awful lot of misbegooten money in fast trains and these ran rather empty after deregulation of air tickets.
Close to bust actually.
This would have angered the voting taxpayers and the voting railroad workers so interior airtravel shorter than two hours train ride was taxed out of existence.

This veers OT whilst your point of view holds valor.

Refreshingly convenient how in the free world successful, profitable private initiative can be banned in order to state-monopolize a market, making end-user pay far more for lesser service.

Luckily the French are saving the planet, what/where would we be without them?.

#### Tom DM

##### Well-Known Member
Supporting Member
Running new common rail engines on Jet A is no small matter. Diesel no problem. Adding a 2 stroke lubricant may address lubricity, but the viscosity issue will remain. And was we know, jet A is plenty volatile enough to ignite in a crash. Thus, for local flights it is no problem to have a caddy with enough diesel on hand. But on a cross country, the number of airports with diesel availability is near zero.

The piston diesel aircraft engines all can use indiscriminately diesel or Jet A - fuel. I suppose that is linked to the "low altitude" they operate on. IIrc Thielert autorised 14000 ft as maximum altitude but it is rumoured that some Diamond-testers took the plane above FL250.

It would be interesting to know if prolonged use at the high altitude temperature would impose measures to keep the diesel liquid. But then: a lorry with diesel engine started at -32 degree celsius and kept on running.

The safety concern of diesel igniting in a crash seems looking for stick to hit a dogs: du to impactforces and released energy almost any material has a possibility to ignite. It is not the first time a flat tire set the landing gear on fire during landing. US Army (as all armies) found out that the use of diesel to gasoline was quite preferable in surroundings where their vehicles were shot at.

#### Battler Britton

##### Well-Known Member
Well well, then you are the first private person outside UK and US I "know" -even if it is through a forum- who bought one.
For which airplane was it intended? Which production number?
Well, it was for small racer, kind of Caudron C 680 not a perfect replica, but a very good "évoquation"
I went very far on the project, small plane, and very fast one ( the size of a Cassut, 120 HP, low drag, small wings)
But I loose slowly interest, due to money, paper around light aircraft ( regulation), so many other project.....
As you write, somewhere here, we are not in the US, and every thing with light aircraft is growing worse ad worse, over there. After owning 5 airplanes, I decided to stop , and look for ultralight
At first with this engine, on a bipe...
But money, again, I'm not sure, today. The project still running, but I also need money for my house!!!!

Saw your avatar and know Candillargues quite well. Nice hangars, lots of builders there, the fire-combating airplanes and the anti-mosquito-brigade with the choppers. Take off over Etang d'Or often watched by flamingos.
I work for 5 or 6 years, with moskito killer! with Grumman AgCat, and Thrush, and of course those magnificent
Pratt & Whitney 1340....
Now , still living near Candillargues, but working mostly in Ethiopia, and Djibouti, 2 month on, 2 month off
Is the pizza-guy at the entree of the airfield still around? He opened up especially when "les Belges" flew in.
No more pizza guy...... But every years, ''les Belges" viennent et boivent des bieres autour de grillades!
Sorry, my interests in the WAM-120 are academical but if you still have contacts there: please to look around for an O-200 loonley on a shelf or for some-one interested in a semi-free, flyable Jodel D113 (but missing its engine)

#### PMD

##### Well-Known Member
Regarding using JetA (or A1 outside of USA) in a diesel engine: since several have gone before, the issue (lubricity) has been addressed and dealt with. Reality is: if you are going to buy the hardware, it will 99% likely come from Bosch Aviation who are not new to the question.

When it comes to using diesel at altitude: first world (and increasingly second world) economies use either US ULSD or Euro EN 590 (Euro V) that are blended not only to deal well with temperature, but with FAME to deal with lubricity (and virtue signalling PC requirements) and are a very consistant product. Where the trouble would come is if one decided to use an old spec D2 at great altitude (ABOVE the middle altitudes into FL180+ controlled airspace) where gelling might be an issue.
Here, we routinely start and run diesel engines in cars and trucks at -45C - something we can do now with ULSD but was a big risk years ago when one might have been returning from a US trip filled with D2 that WOULD gell at -25/-30,

While we scoff at this from our comfortable fat-cat Western websites in Mom's basement, reality is that in many developing nation markets (where avgas is totally absent or insanely expensive) something at a motor vehicle pump might be labelled as ULSD/EuroV but it could well be a bunch of high sulphur, low quality garbage. Thus why in such markets you would want to stick with JetA1. BTW: The real market for multi-fuel flexibility in 200-400 HP CI aircraft engines is very much in developing nation services, but there is little need to go to nose-bleed altitudes for most of that kind of flying.

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#### KeithO

##### Well-Known Member
PMD, my statement would be regarding running Jet A through the hardware provided on the engine when you take it out of the car. At that point it would not have Bosch aviation hardware on it.

#### PMD

##### Well-Known Member
PMD, my statement would be regarding running Jet A through the hardware provided on the engine when you take it out of the car. At that point it would not have Bosch aviation hardware on it.
Yeah, sorry - I should have thought of it in that frame of reference. Problems with being too close to the certified world these days.

#### KeithO

##### Well-Known Member
I had a 2009 Jetta Tdi, the fuel system on it failed in the first 30k miles. If that repair had not been covered under warranty it would have forced the scrapping of the car because it was so expensive. 4x piezo injectors, fuel rail, high pressure lines, high pressure pump. And all the labor. I think one would accomplish the same result in a very short time running on Jet A on the automotive parts.

Perhaps a good system would have a high pressure filter after the high pressure pump to protect the parts downstream of the pump ?

#### PMD

##### Well-Known Member
I had a 2009 Jetta Tdi, the fuel system on it failed in the first 30k miles. If that repair had not been covered under warranty it would have forced the scrapping of the car because it was so expensive. 4x piezo injectors, fuel rail, high pressure lines, high pressure pump. And all the labor. I think one would accomplish the same result in a very short time running on Jet A on the automotive parts.

Perhaps a good system would have a high pressure filter after the high pressure pump to protect the parts downstream of the pump ?
This is one of the things that caught Thielert out during early days of the 125/135. They had both high and low pressure failures, but IIRC they did a lot of their own stuff inside of the pump and in the end increased surface hardness of finish quality to make it last.

CP4 pumps (later VW/GM/Cummins) failures are legendary. A lot had to do with fuel contamination and a lot to do with earlier US spec ULSD vs. the FAME containing Euro IV of the time with much better lubricity. Jet fuel is definitely a challenge in this case. And the failure you had was not exactly common, but occurred a lot with early VW HPCR systems. Not sure there is a commercial filter fine enough to protect the system from failure before the pump or contamination downstream after pump failure.

VW is often featured in these kinds of stories - mostly because they are often the first into a new tech or market area. As one of my elder mentors used to say about this: "You can always tell the pioneers by the arrows in their backs".

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#### Tom DM

##### Well-Known Member
Supporting Member
This is one of the things that caught Thielert out during early days of the 125/135. They had both high and low pressure failures, but IIRC they did a lot of their own stuff inside of the pump and in the end increased surface hardness of finish quality to make it last.
snip

VW is often featured in these kinds of stories - mostly because they are often the first into a new tech or market area. As one of my elder mentors used to say about this: "You can always tell the pioneers by the arrows in their backs".

All - big companies as well as we- seems from time to time to forget while Earth is small, the world can be a big place with local products, climate, etc.

Volkswagen, BMW, Porsche ... all mainland-European brands encountered it. UK and Italian manufacturers evade that sitation nicely: their cars came/ come always with errors, described at "cararater". Such needs no correction but either to be lived with or admired.

The "arrows in the back" holds truth. Rarely the innovator/ risk taker gets the rewards, quite often those go to a clever copier who learns from the mistakes and makes his product just a bit better. If the innovator is small or disturbs an esthabisled market often the arrows do not come from the public.

#### PMD

##### Well-Known Member
The "arrows in the back" holds truth. Rarely the innovator/ risk taker gets the rewards, quite often those go to a clever copier who learns from the mistakes and makes his product just a bit better. If the innovator is small or disturbs an esthabisled market often the arrows do not come from the public.
Yes, and we spell that "J-A-P-A-N"

#### tspear

##### Well-Known Member
Supporting Member
Yes, and we spell that "J-A-P-A-N"

Not in the last few decades. I will leave it to the reader to pick which country they want to name.

Tim

PMD

#### Chris Matheny

##### Well-Known Member
Supporting Member
Back on the lightweight (hopefully) diesel subject. I bit the bullet and purchased a GM 1.6 diesel engine from a wrecked Equinox, it is the same as the Cruze engine. I will be picking it up while I am traveling this week but when I get it home I will do weight thread just like I did for the BMW M73 V12 I purchased last year. We will finally be able to put numbers to at least one more engine.

#### PMD

##### Well-Known Member
Will be interesting to see the weight of the GM engine all up with reduction drive, cooling, etc. Wish there was an automotive installation that was really as light as the technology promises, but I have as yet to see one. No reason IMHO that a dedicated CI design can't match up to THE highest energy density certified SI recip (Rotax 912).

#### KeithO

##### Well-Known Member
$2600 to$3500 (some sellers want \$3500 for a bare long block). Would have to see about whether a conversion from the fancy injectors to passive nozzles would be possible, then run a rotary distributor pump, just a single wire needed to run the engine and even that could be eliminated if one went with a mechanical shut off valve. To keep the common rail system would require a lot of custom electronics. In standard configuration 136hp at under 4000rpm. It has a fancy turbo also that likely would need to be simplified for an aviation application (variable geometry).
I believe the engine only ran for a couple of years in production, so one would likely need to buy a spare engine to have on hand for when it is needed, instead of waiting until needed and then being unable to obtain one.

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#### rv7charlie

##### Well-Known Member
Supporting Member
Wish there was an automotive installation that was really as light as the technology promises
Diesel will be really tough, but there are some gas engines that achieve Lyc/Cont weights, as long as you're talking about higher HP engines. If you're willing to add sport-craft engines to the mix, it's pretty easy even with lower HP engines these days.

The LS motors seem to come pretty close to 300+ HP aircraft engines' all-up weights. They'll probably beat an old Cont O/IO-470's flying weight.
A Mazda Renesis will match a Lyc IO360 (angle valve) with ease. My FWF weighs ~335 lbs less fluids (but *everything* else, including a 15 lb muffler), with dual alternators. A bare IO360 weighs ~330 lbs, before exhaust, baffling, oil cooler, etc. Cont IO360 weighs a bit more than that.

The Yamaha sled engines are now up in the 180-200 HP range @ <200 lbs, including a reduction drive, so they'll beat a Lyc by a lot. Competing mfgrs seem to be pretty similar.

#### Voidhawk9

##### Well-Known Member
Supporting Member
The Yamaha sled engines are now up in the 180-200 HP range @ <200 lbs, including a reduction drive, so they'll beat a Lyc by a lot. Competing mfgrs seem to be pretty similar.
Last time I looked at these, they had incredible power:weight, however that power was for brief periods only, max continuous being MUCH lower. May have changed since then?

#### KeithO

##### Well-Known Member
Last time I looked at these, they had incredible power:weight, however that power was for brief periods only, max continuous being MUCH lower. May have changed since then?
There are people with already over 500 hours on their Yamaha engine conversions. I personally would not like to do a cross country with such a high revving engine droning away.

#### rv7charlie

##### Well-Known Member
Supporting Member
Last time I looked at these, they had incredible power:weight, however that power was for brief periods only, max continuous being MUCH lower. May have changed since then?
I haven't seen any 'official' docs that say that; can you cite a reference for it? I know it's a commonly held belief about non-aviation engines in general, but for most modern engines it just isn't true. The torture and number of hours they put modern automotive engines through during testing makes the FAA test cycle for certifying an a/c engine look like a leisurely drive to the grocery store. I'm less informed about sportcraft engines, but given the ability of most 'Bubbas' to abuse their rides...