"Inventing" a "New Multi-Fuel Engine"

[Domodude17]

I suppose this is where I'm really proving that I'm new to this game, but is there any particular reason full time boost from a small supercharger isn't an option? Will the engine fail to start or will something break? I know some of the old Detroit diesels had superchargers on them so they were most likely going when the engine started up

 

[Jeepsinker]

They are two stroke diesels and will not run at all without the charger. You would do well to do some more research on Diesel engine theory of operation on both two and four stroke diesels.

 

[phil2968]

The two stroke Detroit's did not use the blower to make boost pressure. It simply supplied the engine with a fresh air charge when the intake ports at the bottom of the cylinders were uncovered at the same time the exhaust valves at the top were open.
Later they added turbos that built pressure though the blower when the engine was under load.
I had the pleasure a couple of years ago of watching two 16V92's pulling two 1100kw generators running in sync! (Back up power for City of Tampa lift station.) It was a beautiful noise. One turbo for each four cylinders!
Find some interesting reading here. http://www.dieselduck.info/historical/01 diesel engine/detroit diesel/

 

[frank8003]

oldMan99
Maybe Buck can make one of these as a multifuel for you.
http://www.buckdiesel.com/index.php?Section=Home

 

[patracy]

oldMan99
Maybe Buck can make one of these as a multifuel for you.
http://www.buckdiesel.com/index.php?Section=Home

That modular design looks like it'd be handy to build something like this. I wonder if they could sell an engine that isn't meant for marine use? (EPA) The stumbling blocks will be the need for them to form a new head casting, new piston design, and change the fuel injection system completely. That common rail system DOES NOT lend well to anything other than diesel fuel.

 

[Domodude17]

That does look like it could be a promising avenue. It looks like they cast a lot of the stuff themselves, I wonder if they could be talked into supplying an un-machined head, if there would be enough material to work with. Otherwise we're gonna need to cast our own heads or machine them from a large block of billet aluminum $$. What direction would you go with the fuel injection system instead of common rail?

 

[patracy]

Problem is, the off the shelf casting isn't going to have the proper injector angle (and the piston needs to be changed as well). You'd need to start with a billet blank and start from scratch. A heaping of cost involved in that. And you'd probably want the head to be iron, not aluminum. As to the fuel system, something simplistic like the multifuel pump or a bosch p-pump with a lot of tweaking and custom injectors/nozzles. You're going to want a crankcase lubed IP, not fuel lubed.

 

[Domodude17]

That is assuming the casting has the injector angle cast into it. It probably does, but there is always a slim chance it does not. Perhaps we are thinking too big at the moment. It would probably be loads easier and cheaper to take something like an old couple HP diesel engine from a lawnmower or something single cylinder to play around with to prove the concepts, injector angle, head size, piston design, etc. Wouldnt need to buy a massive billet to replace an entire head, just one. It would definitely need to be incredibly robust to handle the compression though, which has me leaning towards something older and heavier. Any suggestions?

 

[patracy]

You'll need to completely change the injector placement in that head design. It's a 90* setup with a even spray pattern. This would also effect the intake/exhaust runners.

Let me step you back a bit.

What are you trying to gain exactly? The ability to run what as a fuel? If it's gasoline, then yes, we need to continue on your path. If it's Diesel, Kerosene, Jet A/exc, WMO, WVO, then no, we don't need to reinvent the wheel here.

 

[Domodude17]

Well, I suppose in the kind of scenario many of us try to plan for then gas would probably be the least available fuel, not to mention how fast it goes bad anyways. The ones you listed are definitely going to be more common, so if we kept it to those we can probably account for 95% of all the fuel that would be available. I know diesels will run on WMO/WVO without modification, but it is better if theyre warmed up and thinned first. Perhaps we could make some adjustments to allow the engine to run better on a variety of fuels instead of optimized for diesel. Maybe enlarge the injector nozzle and add a FDC or something.

 

[patracy]

So why not just use the LDT/LDS, or as an upgrade a 5.9 Cummins with a p-pump if more power/speed is your goal?

And enlarging the nozzle will only increase flow while decreasing injection length for the same pressure. The FDC is often bypassed in the multifuel as that's not what gives the multifuel it's ability to burn different fuels. It's purpose was only to adjust the power output between fuels.

I'd suggest reading more about diesels and alliterative fuels before trying to reinvent the wheel here. If you're not looking to be able to burn gasoline, the end result can be obtained from production engines already out there.

 

[Domodude17]

The point is to make a NEW multi-fuel engine. I know a lot of people would probably like a smaller version of the multifuel that they could use to run small generators and the like. So if we are okay with omitting gasoline, it sounds like a 5.9 with a p-pump is probably the way to go. So we know that a standard diesel can run on WMO and WVO, but does anyone know how well a standard diesel would run on kerosene, JetA, etc. It is definitely less common

 

[patracy]

Reading up on the forums will present to you that the military runs diesels day in and day out on JP8. (Close to Kerosene/Jet A)

 

[Wolfen]

In cold Climates Kerosene is often used in Diesel Engines in the Winter.

 

[Drizzet]

Hope someone is still interested in this thread and I am not breaking any rules by reviving it. I have been lurking and searching this former in my quest to build an amazing multi-fuel Duce I have time to wait and God has blessed me with some money to spend on my passions. I found a guy in southern Oregon who is knowledgeable with both diesel and MV’s and has done some research on the m35a2 and while we at first started with the idea of customizing a deuce to get me up to a good cursing speed and able to clime hills with out having to pull over every to let traffic by. After talking about it for a while he thinks it would be easier and more reliable to make a 8.3 or 5.9 Cummins multie fuel or as close to as we can get. My question is is there anyone who has knowledge about making it more of a multie fuel then just changing the CR ratio. Like how to fab up or make the cups that go on the engine ? Or how to modify the injection to furth the goal.

I am totally aware this is impractical but to me it is worth it if I can get a Duce with modern parts! And it’s been a fun journey.

 

[frank8003]

"if I can get a Duce with modern parts!"

Why start in the middle? Make your study from the beginning.
Start pre 1954 and get out your slide rule.






View attachment MANN US2907308 full patent too.pdf

 

[Drizzet]

So on a new engine one would have to modify the top of the piston head and the injector to mimic the old multie fuel engine is there any experts on this sight or a company anyone knows that I could talk to about reproducing these ?

 

[snowtrac nome]

in the arctic we run diesels off jet -a my yellow cat runs just fine on it If you wanted to get into some real exotic fuels like crude oil how about a gas turbine, depending one how you adjust metering you can run natural gas petrol diesel products right up to crude oil. they are not efficient in small packages.

 

[Beyond Biodiesel]

From running DIY diesel fuels on 2 different diesel engines in 12 years of research, it looks like any diesel engine can run almost any fuel, as long as that fuel meets the basic spec of a specific gravity of .850. I find as long as my fuel blend is .850sg it will burn like normal diesel fuel in the above two engines with no firing problems; and the engine acts like it is running on ULSD diesel fuel from a fuel station.

So, as long as you have available to you light fractions, like gasoline or kerosene, to blend with heavy fractions, like WMO and/or WVO, in the correct portions to get to a .850sg, then you are good to go on any diesel engine. So, purchase a .800 - .900 hydrometer, and test all your DIY diesel fuels with it, before you put your DIY fuel into the fuel tank.

 

[Drizzet]

Yes I am working with a mechanic who told me that he’s building outa Cummins that will burn those ratios. How ever we have found that we need to find someone who could recreate the pistons with those bowl shape to be able to burn stright wmo/wvo. So my search for someone who could create such a piston is my next goal.