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Where are these engines now?

Where are these engines now?

Where are these engines now?

What new cars or trucks are now cruising around the freeways using these engines for power? The Achates, and the HCCI Mazda engine. This is years later, what happened?

RE: Where are these engines now?

Skyactiv-X is available in Europe. Achates appears to be dead as a doornail.

RE: Where are these engines now?

Maybe they're too busy developing their engine to update their website?

In Achates case, you have to acknowledge that any engine itself is mechanically quite efficient. Changing the mechanics of the engine is going to do little to improve efficiency. The changes have to be made in the cycle which Skyactive does but Achates does not. Achates was doomed to fail from the beginning.

RE: Where are these engines now?

Achates was and is old school. Brand new engines of similar design are coming out of FM factories all the time.
I would bet their down fall is that it is not built strong enough. I thought that FM was in on Achates so you would think they could have something viable by now ?
So the Skyactive-X must work too good, else it would be here as well.

RE: Where are these engines now?

Skyactiv-X is sold in areas subject to CO2 emission limits, where low fuel consumption is a priority.

RE: Where are these engines now?

The only opposed piston engines coming out of FM's factory are for legacy support, replacing engines in special applications. Otherwise, they have a full line of modern 4-stroke V engines.

RE: Where are these engines now?

The FM OP was heavily used in WW2 on submarines which worked well as far as the Navy was concerned.In fact the Navy is about the only customer for thee engines for emergency diesel generators on nuclear powered ship.

After the war FM tried to break into the locomotive market and did well for awhile. I haven't seen a definitive reason why they failed, apparently because they were maintenance hogs. My theory is that with vertical cylinders with the exhaust piston at the top that it could't be adequately cooled with coking of the oil causing heavy wear on the piston rings. To change out the piston et. al,yyou first have to remove the upper crankshaft. The achates engine looks like its trying to get around this by laying the cylinders on its side to get a better flow of oil into the piston.

Locomotive builders tried it about 75 years ago but gave up. the Baldwin unit realizing it had to do something about the upper crankshaft problem probably tried the offset crankshaft with rocker ares but they gave up too.

RE: Where are these engines now?

The two stroke engines have a key benefit in backup generator applications which is their ability to take 100% load in a single step. EMD and FM are both 2-strokes. However, the FM engine excels in rapid start applications vs EMD because the EMD does not have pressurized oil feed to the piston carrier and wrist pin so the engine can't be fully pre-lubricated. There have been failures of EMD engines in nuclear plants due to start-up wear.

As for piston ring wear, EMD had already adopted heat dams in the piston which greatly prolonged piston life. I wonder if FM had similar designs? Having to remove the upper crankshaft to change a power assembly on an engine with a short piston life wouldn't be ideal.

I found this picture which does show the heat dams so they were present in later model engines. They also appear to have adopted the EMD piston carrier. I wonder what years these changes occurred.

RE: Where are these engines now?

Skyactiv-X is available in Australia (no CO2 limits here and pretty slack emissions rules in general) but it is a pricey option and doesn't meet the early fuel-savings claims (according to the journalists that have tested it)

je suis charlie

RE: Where are these engines now?

Not true Tugboateng,

(((The only opposed piston engines coming out of FM's factory are for legacy support, replacing engines in special applications. Otherwise, they have a full line of modern 4-stroke V engines.)))

The OP is constantly being developed.
Much better engine design than most out there. Very efficient as well.

RE: Where are these engines now?

That project seems to have gone radio silence the same day as Achates. No news in 3 years means the project is dead. Most medium speed engines hit that 40k hour TBO decades ago, even the high speed engines are approaching that figure now. Labor is so expensive nowadays having to pull a crankshaft to change a power assembly is simply unacceptable.

RE: Where are these engines now?

I suppose you do have a good point about the power assembly. That would not be a fun job to do on an OP engine. That is strange about the radio silence deal, I wonder what has happened?
Do you think since Fairbanks Morse was sold, that has changed things?

RE: Where are these engines now?

Have you ever walked by an old building with the original sign despite several businesses having passed through? It costs money to remove sign, webpages, etc. These companies are all bottom line driven. The website is a relic. FM has a weak portfolio and a small customer base. The nuclear backup industry is the only thing keeping them in business. I was really surprised to see them advertise a 6.5ish inch bore 4-stroke in the 3000 horsepower and meeting tier 4. As far as I know Cat and MTU are the only two manufactures that can hit that number and MTU is late to the game. FM is likely selling another manufacture's engine under their name if they have pulled this off.

Edit: FM has made a business of supporting defunct lines and selling other brands engines. They support the FM and AlCo lines. They partnered with SEMT Pielstick so they could sell US built French design engines to our military and their 175F engine must be an adaptation of a Man B&W engine assembled in USA so they can be used on military boats or ships.

RE: Where are these engines now?

All true about what they have done. I'm sure like all business they have found corners to cut, I'm not sure but it looked to me like that Trident OP engine had a cast frame instead of the weldmet like the original OP engines had, I'd like to know for sure. Just a personal thing, I just think weldmets or cast steel is better for larger engines due to the ease of repair when something major breaks and opens up large areas of crankcases and blocks.

RE: Where are these engines now?

It took 20 seconds to find this announcement dated 1/28/2021. I know from experience that work being done for the military can't be publicly discussed without their permission, and the Army likely has no interest in details of their research and development efforts being made public. Contract awards, however, are public record (unless related to a special program), and the government usually approves them with scant review. I also know from experience that companies are seldom awarded follow-on contracts unless the initial effort yielded success (or at least promising results). Of course the true indicator of success is a production contract, but those often come a decade or more after the first R&D award due to operational test requirements (that's why the computers in their new vehicles are obsolete the day they're fielded). As for FM producing brand new opposed piston engines all the time, I can only say that military procurement is highly risk averse, so if FM had something close to what they needed, the Army likely would have contracted with them instead of Achates.

RE: Where are these engines now?

20 seconds to find something that didn't exist at the time of my post.

RE: Where are these engines now?

Having spent 3 decades dealing with the US Military, they are not so much risk averse as they are mission focused, sometimes regardless of financial risk.

They are also driven by the Senate and the House to buy things the military does not want in order for politicians to buy votes in their states and districts.

The main contributing factor to old tech isn't the delay to production. Our products, including high-density test equipment, depended on using established parts with known histories and likely future supplies. That alone puts them 3-5 years after initial release for initial consideration. Choosing a part that seems promising and fails in the market is a killer. Mostly we went from prototype start to production start in about a year, often overlapping the end of qualification with initial production.

Aircraft and ships are going to be the exception, but the military doesn't have such long production horizons for ground vehicles and test equipment; at least most of the horizon is spent internally generating requirements and arguing for funding.

Since this engine concept was used in production vehicles starting nearly a century ago and was generally abandoned in favor of valved 1 piston per cylinder engines I wonder what previous problem is being overcome that caused them to fall from favor previously. OTOH I keep seeing major announcements on gCaptain over sailing cargo vessels.

I'll be sketching up some horse-cart designs if this continues. Carbon fiber and ceramic bearings this time.

RE: Where are these engines now?

The way most auto manufacturers are talking, the entire concept of internal-combustion has a pretty limited future. No one is going to take the risk putting something massively different into production only to retire it in not too many years.

RE: Where are these engines now?

Oh, I think the old girl has legs yet. Ammonia. IF the fabled hydrogen economy comes about (probably as likely as fusion) then ammonia burning engines are a great solution for non urban transport.


Greg Locock

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RE: Where are these engines now?

3DDave, I spent 3 decades designing, proposing, and leading development of deployed systems, some of which included test stations. I designed and personally wrote the winning technical volume for the ALR-69A(V) Radar Warning Receiver proposal in 2001 (the program kick-off meeting was disrupted by the events of 9/11). The Low Rate Initial Production contract wasn't awarded until 2009. The first real production program with DOT&E approval wasn't awarded until 2012, and the long anticipated billion dollar production contract wasn't awarded until 2018. I also designed and wrote proposals for quite a couple of other programs I'm not free to discuss, and every one of them took a decade to full operational deployment. One is still in the pipeline even now after seven years of retirement.

Some of the worlds world's most efficient engines are opposed piston two strokes. They have pretty elaborate schemes for metering lubricating oil to prevent it from being scraped out the exhaust ports, a problem that has plagued the architecture since the Junkers Juno engine. The technology required to manage oil the way it's managed in modern opposed piston engines didn't exist until comparatively recent times. The US Army's team lead summarized the objectives of the program saying "The results of the ACE engine utilizing an opposed-piston design architecture will provide significant improvement in thermodynamic efficiency over commercial-off-the-shelf engines while increasing power density, improving vehicle mobility, and reducing fuel consumption and thermal burden". Whether these objectives are met is TBD, but the fact they're awarding follow on contracts is a good sign.

RE: Where are these engines now?

Brian Peterson, It's clear that electric will continue ascending insofar as the charging infrastructure is in place. That's going to be quite some time out in the boondocks where they don't yet have broadband internet, and the military certainly can't assume infrastructure is in place during field deployment to combat zones (fixed military infrastructure is called a target by the enemy). The military will always want to bring their energy with them rather than depend on foreign infrastructure in a combat zone. I doubt they'll go electric until they can get 300 mile range in a 70 ton electric M1A2 tank that can be charged in ten minutes using a safe portable reactor.

RE: Where are these engines now?

Good - we are even. Note that I avoid talking about any projects, for similar reasons. I'm impressed about solo writing a technical volume. Normally that requires a large number of experts. However, not every contract goes to a company that has enough Senators to drag it out.

RE: Where are these engines now?

Yes, military applications are their own separate situation, and there are certainly situations with road vehicles that are going to be difficult for all-electric to accommodate. But still ... recent pronouncements by VW and GM, among others, make it pretty clear that they're not going to be investing much in combustion-engine technology going forward - they're just going to go with what they've got. If the military needs to do something special, they may be on their own.

RE: Where are these engines now?

I suspect the current crop of ICE consumer engines have such small margins for improvement that the extra complexity required outweighs the benefits while there are huge opportunities are now in electric power.

I see, looking back at the Achates press releases, 25% to 30% fuel use reductions and claims they are far less expensive to build, seemingly far into the territory that every long-haul trucking company would see as beneficial, but it doesn't look as if they are as excited about it as US Army Tank Automotive Research, Development and Engineering Center (TARDEC) is.

It looks like the originator of this effort shrugged off the mortal coil in Feb 2019, so I expect that took a toll on the process. RIP Lemke.

Anyway, for those interested in Achates: https://patents.justia.com/assignee/achates-power?... is a good collection; easier than the USPTO to scan through.

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