We've been running and attempting to tune the Maybach engine in this thread. http://www.jalopyjournal.com/forum/showthread.php?t=228797&highlight=maybach I'm wondering how you compensate for the difference in the fuel qualities? I've jetted the 4 carbs. like original and am having a hard time getting the mixture lean enough when the engine is running in the idle circuit. Does anybody know how these fuels would be different and how you would change the jets to compensate? Thanks for your help DAVE
send a private message to jimbob here, he restores vintage military aircraft for the australian war musuem, and is in contact with other such places round the world.. if he cant help you, you're probably on your own as to knowing the specs of ww11 fuels.
Would they have run it on Av-gas? Fuel was a problem for the Germans especially later in the war. Is it possible the thing was de-tuned to run on lower octane fuel? Years ago I had a buddy who maintained some vehicles for a small movie production company. They had a WWII era deuce and a half (Studebaker I think) we went riding around in one day. I remember reading the data plates on the dash where it said minimum octane was like 52! Kurt O.
Thats your problem,You have a slow burning fuel in an engine designed to run on more volatile low octane crap . I would lower the fuel pressure first ,then use as low an octane as possible while checking exhaust temps to ensure it's running OK. How are your plug readings? . To say the Nazis' had fuel problems is an understatement.Operation Barbarossa was mostly about securing the Caucasus Oil feilds .Under Feild Marshall Paulus the 6th Army was Defeated outside Staligrad,mostly because of lack of fuel.
Just a thought but if you are having a rich run problem,I would check to see if:1) you have an altitude compensating device and if so:2) is it functioning properly.As the aircraft's altitude increased,there had to be a method of richening the mixture to maintain a proper air/fuel ratio.If the altitude compensator wasn't operating,it might cause the engine to run way too rich.
The Russel Group owns and flies an original Bf109 with the original engine. They might be able to help or point you in the right direction. http://therussellgroupairshow.com/
The Axis was plagued by low-quality fuel throughout the war. The Germans had a program whereby they recovered, repaired, and tested downed Allied aircraft; they also captured intact ones by luring them with false radio beacons. After losing a few engines in these planes due to detonation, they drained and stored Allied fuel and lubricants and used them exclusively in their test program. The Japanese used water and alcohol injection in their engines to fight detonation and employed lightweight designs to cope with reduced power. In his autobiography Gen. Jimmy Doolittle credited the development of high-octane aviation fuels before and during the war with allowing the development of war-winning aircraft. Before the war he was manager and test pilot for the Aviation Division of Shell Oil, which produced the first batches of 100+ octane avgas. Aircraft and petroleum development went hand in hand in the 1930s. BTW I know this is a tank engine. Maybe they would have run it on ordinary gasoline?
In WWII allied forces bombed the Polesti Romania oil fields thus destroying the Nazi' fuel supply and they turned to making ethanol after 1944. Contact some of the aircraft museums that have flyable restored aircraft and see what they can tell you.
Without getting too far into this,the IG Farben concern ,was decades ahead of the rest of the world in gasoline research. They were producing 300,000 + barrels of synthetic fuel per day in 1943 at fucking Aushwitz. In the 1920's American oil companies were astounded at the level of research going on Germany into fuels etc .
Indeed. But research is one thing; production another. There's so much to read on the subject; especially concerning the fuel requirements of historical engines like the Maybach tank engine. http://en.wikipedia.org/wiki/Gasoline "Most German aero engines used 87 octane fuel (called B4), while some high-powered engines used 100 octane (C2/C3) fuel. "This historical "issue" is based on a very common misapprehension about wartime fuel octane numbers. There are two octane numbers for each fuel, one for lean mix and one for rich mix, rich being always greater. So, for example, a common British aviation fuel of the later part of the war was 100/125. The misunderstanding that German fuels have a lower octane number (and thus a poorer quality) arises because the Germans quoted the lean mix octane number for their fuels while the Allies quoted the rich mix number for their fuels. Standard German high-grade aviation fuel used in the later part of the war (given the designation C3) had lean/rich octane numbers of 100/130. The Germans would list this as a 100 octane fuel while the Allies would list it as 130 octane. "After the war the US Navy sent a Technical Mission to Germany to interview German petrochemists and examine German fuel quality. Their report entitled “Technical Report 145-45 Manufacture of Aviation Gasoline in Germany” chemically analyzed the different fuels, and concluded that “Toward the end of the war the quality of fuel being used by the German fighter planes was quite similar to that being used by the Allies.” "American aviation fuel was commonly 130 to 150 octane. This high octane could easily be used in existing engines to deliver much more power by increasing the pressure delivered by the superchargers. The Germans, relying entirely on "good" gasoline, had no such industry, and instead had to rely on ever-larger engines to deliver more power." It's a pretty complicated subject to say the least!
I have a book that shows the required octane rating at "74" This number is listed with the engine technical information. I don't know what modern number this would equate to? On most of our other vehicles we use low lead av-gas for the lead and preservatives that supposedly help the fuel last longer in storage. On the Maybach with 6.8 : 1 compression it sounds like this may be a poor choice. I'm wondering if we should search out the lowest "quality" fuel and use an additive for the valves? I knew the HAMB would help with my quest for information. It's like one stop shopping for technical information on old weird stuff! Thanks for your help...DAVE
Try mixing in coleman fuel a bit at a time the stuff need to burn a lot quicker not slower my guess is that 40-60% Coleman is where you will end up My engines require OZ 80 But I have seen ratings far below that listed for some engines Do you see a ''OZ'' spec on the motor somewhere? There were so many different ratings that engines commonly said on them what fuel to run.
We ran a lot of 1710 Allisons on farm water pumps (non supercharged). We used regular gasoline just fine as the compression and loads were mild for this engine. If the engine is not supercharged, it is usually set up for a low octane fuel. Tanks had to live off the land sometimes and take fuel from a wide variety of sources. If switching from low octane to high octane, one usually must lean the jetting...conversely if you are running rich on high octane fuel...not able to get a lean idle, investigate using just common regular gasoline with a lead addative. BTW: We used 55 GAL. regular gas with 5 GAL toluene (as anti knock agent) in various exotic engines with success. GL
I think I mentioned this earlier today that you need a fast burning fuel ( low octane) ,the coleman fuel sounds right to me .i would probably ATF to the fuel as a lube agent rather than the alcho based anti knock agents . I have used this High compression/slow quench engines to cut preigniton .In fact you can go to almost 80% toluene ..
God I LOVE this place. While I don't have a technical or historical answer for you like so many others, I could swear I saw a photo not too long ago with a Panzer sitting in front of a civilian petrol station at the pump filling up with soldiers lazing around it.
I havn't found an "OZ" spec yet, but I will keep looking. This engine is currently missing all the external data plates. So far the only number of any sort that I have found is "74" I'll keep searching and see what I find. To start, I'll first switch to 87 and tune the mixture from there. Thanks for all your help DAVE
The bulgarians have ony just decommisioned their WW2 maybach tanks. Most still have nazi markings on them ..ha ha Most look like this though.
I think you're on the right track. Some more info: http://en.wikipedia.org/wiki/Octane_rating "Measurement methods The most common type of octane rating worldwide is the Research Octane Number (RON). RON is determined by running the fuel in a test engine with a variable compression ratio under controlled conditions, and comparing these results with those for mixtures of isooctane and n-heptane. "There is another type of octane rating, called Motor Octane Number (MON) or the aviation lean octane rating, which is a better measure of how the fuel behaves when under load. MON testing uses a similar test engine to that used in RON testing, but with a preheated fuel mixture, a higher engine speed, and variable ignition timing to further stress the fuel's knock resistance. Depending on the composition of the fuel, the MON of a modern gasoline will be about 8 to 10 points lower than the RON. Normally fuel specifications require both a minimum RON and a minimum MON. "In most countries (including all of Europe and Australia) the "headline" octane that would be shown on the pump is the RON, but in the United States, Canada and some other countries the headline number is the average of the RON and the MON, sometimes called the Anti-Knock Index (AKI), Road Octane Number (RdON), Pump Octane Number (PON), or (R+M)/2. Because of the 8 to 10 point difference noted above, this means that the octane in the United States will be about 4 to 5 points lower than the same fuel elsewhere: 87 octane fuel, the "regular" gasoline in the US and Canada, would be 91-92 in Europe. However most European pumps deliver 95 (RON) as "regular", equivalent to 90-91 US (R+M)/2, and even deliver 98 (RON) or 100 (RON)." Also, avgas has different properties than mogas (for motor vehicles) due to the conditions at high altitude. It's lighter (weighs less) and vaporizes more readily in cold temperatures. It may not be the best choice for a ground vehicle. http://en.wikipedia.org/wiki/AvGas Good luck!
"Technical Report 145-45 Manufacture of Aviation Gasoline in Germany" That is something you need. I meant to go hunting for you here, as we have cataloging on Gov docs and National Technical information service Waay back in our library, but looks like he already found one of yor holy grails. Now that you have the name, you need the paper or microfilm. Likely your big state engineering schools that are old enough have it. A good interlibrary loan person in your county system should be able to find where copies live and perhaps borrow them. Oops...only Cornell is listed as having it, but likely other big schools have it not listed online: Translation from microfilm reel no. 138 (Orig. desig. Navy reel 1): "The manufacture of aviation gasoline in Germany". United States. 1947 English Book 12 nos. illus. 28 cm. New York: Consultants Bureau, Get This Item Availability: Check the catalogs in your library. Libraries worldwide that own item: 1 Search the catalog at Drew University Library Borrow this item from another library (Interlibrary Loan) External Resources: Cite This Item Find Related More Like This: Advanced options ... Find Items About: United States. (4,229,193) Title: Translation from microfilm reel no. 138 (Orig. desig. Navy reel 1): "The manufacture of aviation gasoline in Germany". Corp Author(s): United States. Government Technical Oil Mission. Publication: New York: Consultants Bureau, Year: 1947 Description: 12 nos. illus. 28 cm. Language: English Series: Germany document 3, 7, 12, 16-20, 22-23, 26-28; Variation: Germany document 3,; 7, 12, 16-20, 22-23, 26-28 SUBJECT(S) Descriptor: Gasoline Petroleum industry and trade -- Germany. Note(s): "Consultants Bureau. Translation FL1-12 Other Titles: The manufacture of aviation gasoline in Germany. Document Type: Book Entry: 19850724 Update: 20060208 Accession No: OCLC: 63635968 Database: WorldCat -------------------------------------------------------------------------------- Subjects Libraries ILL E-mail Print Export Help WorldCat results for: ti: Manufacture w1 Aviation w1 Gasoline
Next, have your new best friend in interlibrary loan do some searching on OCLC. Using "Germany and (fuel or gasoline)" as a probe, limited to 1944-1949, I found a few more things that seem interesting. Germany was overrun with allied technical intelligence stuff sifting the wreckage and writing reports on German tech. I have their report on field maintenance and repair of tanks squirreled away somewhere.
last night I watched a very interesting film on the german and Russian battles in operation citadel. If I were in a position to restore a tank I think my first choice would be the Soviet T34 ,According to the nazi tankers that survived,the T34 with it's Diesel power and sloping amour was a far superior vehicle. Especially once a round connected with a panzer ,if the heat from the shell exploding didn't cook you,the exploding gasoline did. The battle fought in the Kursk, Orel, and Belgorod area was one of the most important engagements of the Great Patriotic War and the Second World War as a whole. Not only were the picked and most powerful groupings of the Germans destroyed here, but the faith of the German Army and the German people in the Nazi leadership and Germanys ability to withstand the growing might of the Soviet Union was irrevocably shattered. --General Zhukov, Marshal of the Soviet Union.
This is so cool! But think of the irony.........our boys that won the war came back to be hotrodders.......and now 60+ years later a bunch of hotrodders are talking about and restoring a German tank.
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