WD9 MD questions

I did not realize MD starts on gas like the old WD9 we had on the farm, WAY back when I was learning to run tractors.
Any other IHC models start on gas and switch to diesel? Any other makes of tractor start that way? I know tractors were simpler back then but why did tractors start that way? I am not a mechanic, I can guess why, but you guys know why so explain history of this gas to diesel starting, was it an IHC Farmall thing? Thanks, I do enjoy the history lessons you YT guys provide.
 
Farm tractors started like that MD size through 650 diesel.
So they could be hand cranked.
Diesel in that time era didn't start real good in the cold. Engine could be started with close to same difficultly as a gas. Then while running on gas engine was heated enough to burn diesel better when switched. No extra pony engine was needed.
Good idea for the times but had some problems. Be interesting to see what would happen if modern engineering and castings were used.
Another drawback was not everyone wanted to take time for filling two tanks and extra start up time. Even though most diesel engines should be warmed some before use a lot of direct diesel start ones don't get much by a lot of people.
 
Correct me if I am wrong, but I believe it was for easier starts. Much like Kerosene, or 'low cost fuel/distillate', the fuels/fuel-oils burn much better when the engines are at operating temperature. The earlier gasoline tractors were started on gasoline, and once up to operating temperature were switched over to the 'main' fuel. Most early kero/distillate tractors had a small gasoline 'starting tank' that was used to both get a tractor to operating temp, and also to switch back to during 'cool down' to allow for an easier re-start.

With the coming of glow plugs, starting on gasoline was not necessary simply because these would pre-heat the air/fuel mixture immediately prior to starting the engine, allowing easier starts.

John Deere two-cylinder diesel's had a gasoline 'pony motor' to start their primary motor. They circulated the same engine coolant, which helped warm the primary engine prior to start up. Essentially, you would start the pony motor, allow it to warm up, then engage the clutch connecting the two motors. The pony would turn the larger diesel, and once it fired, you would disengage the pony motor clutch and shut it down. Check out the John Deere R, and 80 starting procedures on YouTube (I have enclosed a link). Pretty interesting starting procedures. A friend of mine has an R, and that thing is impressive when it runs. 5 3/4" bore x 8" stroke, and while running it sounds like a diesel motor in a small ship. The tractor also has a rhythmic 'bounce' at idle. Pretty neat.
John Deere R Startup Procedure
 
In addition to the MD and WD6/9, there were the 400, 450 and 600 series wheel tractors. Also the WD40 - IHC's first start on gas diesel tractor. For crawlers there were the TD6 thru TD24 tractors.

The start on gas method was unique to IHC. Another manufacturer of stationary engines (Waukesha? Murphy?) dabbled with gas start diesels. But few if any made it to market. John Deere and Caterpillar opted for separate small gasoline cranking engines (aka "pony motor") for starting their early diesels.

Reason for the gas start ease of cranking. It was possible to start an MD, WD6 and WD9 a hand crank. Otherwise a modest (ie. inexpensive) starter and battery was sufficient. And unlike Deere/Cat diesels it required no separate pony motor. The downside was complexity - gas start diesels need carburetor, magneto (or coil + distributor) and spark plugs. Also a more complicated and somewhat fragile cylinder heads/intake manifolds.

Fascinating early diesel engines!
 
You correct that all the 2-Cylinder JD diesels until about 1959 had a pony starting motor. But in 59 and 60, JD offered a 24-volt electric starter for the 730 and 830 2-cylinder diesels. I have a 24-volt electric start 830 diesel. It is a somewhat complicated electrical system but it does work well for direct starting in warmer weather. Al
 
Just some added info. A Caterpillar engine's pony start engine routed its exhaust through a tube in the intake manifold. The Diesel engines intake air passed over the tube to heat it thus facilitating a better start. I'm not sure if the JD two cyl utilized that benefit or not.
 
Thinking I need to correct myself. WD40 is maybe the first farm tractor, WD6 the first letter series.
 
Al, Thanks for clarifying that. I was pretty sure that JD got away from the pony starts, but wasn't exactly sure when. Those two cylinder diesels sure have a unique sound and shake to them when running.
 
Funny how you say "tractors were simpler" when the gas start diesel was one of the most complicated designs in American tractor history...

Gas start diesel was a workaround because IH didn't want to pay patent royalties on the glow plug. Much in the same way the Fast Hitch was a workaround because IH didn't want to pay royalties on the Ferguson system.

Notice that the BMD and B-450 had both glow plug start diesel engines, and 3pt hitch in England.
 
They didnt have glow plugs back in the day when diesels were used in engines in the early yrs back in the 30s cause they didnt have batts
 
Ih made several gas start diesels WD40,WD6,WD9,TD6,TD9,MD,400D,450,600,650, plus orchard units, and power units. I'm guessing maybe high crops?

The WD9 and MD were two of dads favorite tractors. Dad had his own tractor repair business. Had several customers that ran the WD-9, 600-650's. The tractors got a bad rep for cracking heads. Dad always said it wasn't the tractor that cracked the head it was the operator.

Dad said everytime his customer got a new hired hand. The old wd9's would come back to his shop and need the head cold welded or the valves replaced. Dad said it took longer to educate the new hand how to operate a IH diesel than it did to repair the damage!

Dad had his own WD9. It was about a 48 model. He bought it at a consignment auction with a cracked head. he cold welded the head himself. Ran that tractor for many years. Dad loaned it out and the dumb guy drained out the anti freeze and put in stright water and it froze.
 
(quoted from post at 15:33:31 04/29/16) Ih made several gas start diesels WD40,WD6,WD9,TD6,TD9,MD,400D,450,600,650, plus orchard units, and power units. I'm guessing maybe high crops?

The WD9 and MD were two of dads favorite tractors. Dad had his own tractor repair business. Had several customers that ran the WD-9, 600-650's. The tractors got a bad rep for cracking heads. Dad always said it wasn't the tractor that cracked the head it was the operator.

Dad said everytime his customer got a new hired hand. The old wd9's would come back to his shop and need the head cold welded or the valves replaced. Dad said it took longer to educate the new hand how to operate a IH diesel than it did to repair the damage!

Dad had his own WD9. It was about a 48 model. He bought it at a consignment auction with a cracked head. he cold welded the head himself. Ran that tractor for many years. Dad loaned it out and the dumb guy drained out the anti freeze and put in stright water and it froze.

What was your father's recipe for long crack free head life?

Thanks,
Dan
 
Dad always said not to run on gas too long when you start the engine. Let it warm up before putting it to work. Let it cool down
slowly after working it. Never run it out of fuel.

The WD9 dad had was about a 48 model. He said he paid about $100 for it not running. Someone had already tore it down before he bought it. They left a box end wrench sticking out of the exhaust. Dad cold welded the head himself. His tractor had a 5ft stright pipe exhaust. It would blow perfect smoke rings while plowing. Dad had a McCormick 4-16 plow.
 
(quoted from post at 16:57:41 04/29/16) Dad always said not to run on gas too long when you start the engine. Let it warm up before putting it to work. Let it cool down
slowly after working it. Never run it out of fuel.

The WD9 dad had was about a 48 model. He said he paid about $100 for it not running. Someone had already tore it down before he bought it. They left a box end wrench sticking out of the exhaust. Dad cold welded the head himself. His tractor had a 5ft stright pipe exhaust. It would blow perfect smoke rings while plowing. Dad had a McCormick 4-16 plow.

Mine will blow smoke rings when it's cold. Must be an MD thing.
 
Thanks for info. I am not a mechanic. Complicated it was. I did not realize it could be done, that it was possible to run and engine on two fuels.
 
yes gas starting was an international think. it was probably one of the most efficient ways to warm up the engine till it warmed up enough to run on diesel. and it would switch over very well and smoothly to run on diesel. the WD40 tractor started on gas by hand cranking it. then after running 900 revolutions it switched over itself to diesel. this was in 1935. the WD9 came out in 1940 and you had to manually change it over to diesel operation. due to the size of the injection pump on those old 40's they had an essentric in them that pushed a rod to trip the diesel operation and close the little gas valves. this was done manually on the wd9's and all others from 1940 on.
 
Disagree not a flame. The Fast Hitch was (is) much superior to the 3pt. The error made by IH was simple. they didn't permit second parties to make implements that fit. nor sell the device to others. Market penetration is everything. Jim
 
(quoted from post at 16:57:41 04/29/16) Dad always said not to run on gas too long when you start the engine. Let it warm up before putting it to work. Let it cool down
slowly after working it. Never run it out of fuel.

The WD9 dad had was about a 48 model. He said he paid about $100 for it not running. Someone had already tore it down before he bought it. They left a box end wrench sticking out of the exhaust. Dad cold welded the head himself. His tractor had a 5ft stright pipe exhaust. It would blow perfect smoke rings while plowing. Dad had a McCormick 4-16 plow.
So what is "cold welding" that will hold up in an IH diesel head?
 
I don't think they are all that complicated when compared to a CAT or JD with a pony motor. Overhauling a pony motor you'd think you'd spent the money to overhaul the main engine.

They had a compression release valve that opened access to the spark plug to allow the same cylinder to burn gasoline or diesel. Lowering the compression also made hand cranking possible. The spark plugs fire after TDC and the engine has very little power. My TD-14 would not even raise the blade while on gas.
 

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