Tinkering up the Old M-20/35

Engine owned by the Oakland Telephone Co

Howard E. Shideler

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35640 Avenue F, Yucaipa, California 92399

When I was a young lad during those golden days on the farm, a group of some 20 farmers went in on shares and purchased a Case 20-40 two-cylindered opposed type gas tractor and a companion 28-50 separator. These fine agricultural instruments were delivered by our good Mr. Jack Kadinger who now resides near Sioux Falls, South Dakota. In the era of open-type drive gearing, I still believe that was one of the very best tractors that was ever built. A very was building fine two and four-cylindered opposed engines, but hamstrung themselves with about the most ridiculous (sliding frame) transmission that one could possible conceive of. -All to save one intermediate gear; which idea was wrong to begin with since a pair of spur gears can be properly cut only to mesh between themselves. The root becomes dislodged if one of a pair of such gears is brought into an improper mesh with another gear of differing pitch diameter than that of the paired original design. One of my brother-in-laws nearly met disaster when descending a good grade with an Avery 40-80 and the frame slid forward out of mesh. And were they bugaboos to handle in the belt!

At that time, one of the most popular other tractors of that rating was the Oil Pull. In the large models (as in the Case 30-60 also) the engines had a 360-degree two-throw crankshaft, which allowed of a more smooth power flow and also a straight longitudinal vibration. However, in the smaller sizes the Rumely builders for some reason went to the 1800-degree crankshaft. The carburetion advantages were the same, as a short downdraft was achieved for both cylinders; but this design entailed a severe cross-vibration such that many owners experienced trouble with the Tim-ken bearings in the front wheels through not keeping them properly adjusted. So, when I became afflicted with the engine bug again some 14 years ago, I considered myself fortunate in finding an old M-20-35 Oil Pull in the junk yard in Spokane, Washington. This specimen I immediately bargained for, and now it sits in my back yard and is called upon now and then to perform some little task. Immediately after finding this old girl, I ran across a sister engine in the junk yard in Pullman, Washington. The latter engine was equipped with angle grouters, which I would have preferred to the spade lugs on the wheels and extensions of my cherished possession. On my little old lady, someone had removed the magneto, put several wrinkles in her fenders, discarded the foot brake and other small items, and, apparently- what had caused her near demise- her former owner must never have looked to the lubricating oil in the separately enclosed governor housing. For I was to discover that not only was this reservoir plumb long since dried up, but the lack of oil had caused the governor shaft to seize and become twisted off. Doubtless some farmer must have had a fast final ride before getting her shut off, and it is somewhat of a wonder that things did not begin flying to pieces.

My first chore after getting the old M delivered to my home at that time in Tacoma, was to rig up an automobile distributor (grinding off all but the two necessary cams) and get her into operation, with battery ignition. Then it was steam cleaning and finally painting, until she 'shone like new.' Then a friend gave me an old Edison-Splitdorf magneto, and I was able to dispense with the battery for a few months until the mag went real sick in its old age. After trying a few other mags, and moving the engine to my present home, I secured an American Bosch four-terminal magneto ; upon which I fixed two spark gaps on the extra terminals, and so far this seems to be doing nicely.

Oh yes, the water tank had long since rusted away, I suppose. And since kerosene or distillate was difficult to obtain, and the engine would not be placed back into full agricultural service anyway, it became of advantage to simply operate on straight gasoline. Actually, the gasoline of today is probably inferior to the kerosene of yesteryear. Of course, there is the problem of detonation and more rapid burning without water, but if one can tolerate the slight diminishment in output power, a good remedy is to set the spark back to about ten degrees BTC. This puts it into the class of other tractors which were built to operate on gasoline, like the old Case mentioned earlier. And since this model does not have the crankcase vent back into the intake system, there can never be any fear from intake backfires. I can vouch that the power output is still adequate, since an instance of hauling long green eucalyptus logs up out of a ditch nearby, the old girl could spin her rear wheels right into the ground if tied down to a standstill.

Now this latter piece of work posed another problem, and if the fool-killer had not been taking his day off I can assure you that I might not now be writing this article. You see, I was backing up to the very edge of a 30-foot embankment of some 60 degrees standing, and tying onto those trees of about 25 feet in length and 24 inches in diameter, with 40 feet of log chain. Well, after hauling in the last of a dozen such very heavy green fellows, I proceeded to put the old girl back under the canopy. And I just made it, for upon the last clutch disengagement, the throw out yoke slid over the worn sleeve engagement! Had this happened while attempting to stop in reverse at the very edge of the embankment, likely the whole works of us would have had the fastest ride ever in her life down that embankment. So we come to the crux of this story and one which elicited a few new swear words from my capacious vocabulary. No matter how good the mechanic, he had always best consult the owner's manual before attempting to make repairs on such design of clutch. But no manual was available, and only through the medium of this fine magazine did I find a great help in the kindly assistance and Xeroxing of some manual pages from such book in the possession of a greatly esteemed friend, Mr. Donald Robbins of Troy, Ohio, who has one of the Super Oil Pulls at work in a sawmill operation. And because this is pretty heavy work without good shop equipment for such undertaking, I put off the job long as I could.

But finally I 'got the spirit' and began tackling the job. Now right at the outset, I want to castigate M. Rumely and his whole force for ever having undertaken to design this clutch layout such that it becomes necessary to take off all the primary gearing (transmission) cover in order to not only slide off the primary drive pinion but all the rest of the hostage apparatus used to disengage the clutch faces FROM THE INSIDE! Good heavens- it is exactly as easy to have designed the throw out mechanism from the outside, similar to the old shoe-type clutches. And in the latter instance the throw out could be disassembled without disturbing another element. The only difference being that the inside disengagement looks a bit neater from the exterior. It was considered very advantageous to design machinery from the accessibility-for-repair standpoint in days of old, whereas nowadays it is designed for a serviceman's dream with all special tools. And, to add insult to injury, these primary gears, having the highest tooth engagement speed in the line, were not even to include a hunting tooth in the larger gear, which would have made no difference of concern in torque but would have eliminated the peculiarities of special gear fitting at the factory for such things as even two-to-one reduction, etc. I did recall that some good chap through the columns of this magazine cautioned about re-meshing these gears tooth-for-tooth during such repair or overhaul. But by this time my unassisted patience (or lack of it) caused me to slam her right back together catch-as-catch-can, with the consequence that her gear howl can be heard for a good half mile in spite of a good dose of molylube. Oh, well, she will come back in, eventually.

One of the things that stressed my aging patience was that, while I had good luck with welding a cast steel ring (made from an old timing gear) onto the throw out sleeve, I did not meet with such success in the case of the collar. This latter I attempted to build up with an arc job and return to dimensions. But the nickel I used against the casting turned out to become so hard that neither I nor any other shop around could wish to tackle the job. I finally secured a carbide cutting tool for the little old Sears 10-inch lathe and finally cut out the built-up shoulders and then proceeded to continue undercutting. Then two steel rings were turned out, split, and welded into the recessed grooves. Upon reassembly, the clutch now works very smoothly and I do hope never to have to disassemble it again-ever -ever!!!

One other item that 'steamed' me up a bit about the design of this old girl was that the oil coolant circulating pump was not only mounted in an inaccessible position for gland repacking, but the mounting casting incorporated a trough-like cast section which provided for no drainage of any leakage past the packing gland. And since there was no packing on the drive shaft side from the camshaft gear housing, it allowed any leakage to run undetected right down into the crank-case. Now, there is no sight-level for the crankcase oil level, so it is quite difficult to ascertain just what is going on in the crankcase on a day-to-day basis. Consequently, I procured a long-shank 3/8 inch drill and bored a vent hole in the bottom section of the pump mounting bracket. This will afford a visible means of pump packing leakage and also keep any such leakage (as I had experienced) out of the crankcase. It does appear strange that this fault should have been overlooked in the engineering design of this series of engines.

Now, after all this, the old spark plugs began cutting out, as though they did not deserve to in relic status. The old plugs were of an extended design of nearly 1-1/2 inches beyond the skirt. This type of plug is necessary in a head design having such deep plug wells, if the engine is to fire regularly under low compression while idling. And that is one thing she did- never missed a pop when standing at a very low speed. I had rebuilt the governor using Caterpillar weights, and this resulted in a very sensitive response, even to causing an extra strong impulse on but a single cylinder when traversing a big of uneven ground. This I like, as she stays right on the rpm regardless. But back to the plugs.

I just about exhausted the Pacific Coast distributors for a long-shank 7/8 SAE plug, but the old cross-references and catalogings now available indicate a Champion W-16 or thereabouts for the job. This is a standard short-shank (non-extending) plug, and will not fire this engine properly while idling. Even my good friend's manual back in Ohio apparently makes no reference to recommended spark plugs. But finally a Good Samaritan came through with a very close dandy- a Champion W-89-D, with a 3/4' extension below the skirt. There is nothing more distracting than to have a gas engine irregularly misfiring on idling, regardless of the number of cylinders or type of crank throw. And if they are of good compression, proper carburetion and hot spark, they will not let out an occasional mis-pop. My old girl never did before, and now she is back into good mettle again. Some operators are of the opinion that, because of the 'peculiar' one-two firing of such two-cylindered 180-degree crank shafted engines, this entails an occasional misfiring on number 2. But let us consider why there is no engineering reason for such behavior. Figure one is a sketch to display the intake and power events in such engine. From tracing through by the respective sequential strokes, it will be seen that 2 has already received its intake charge before number 1 has even fired to cause a momentary speedup in flywheel momentum if the governor is that sensitive! And since number 2 has had equal opportunity with number 1 to receive equal charge, it can hardly dodge putting out an equal power impulse- providing, of course, that this second cylinder has a spark equal to that of the first cylinder. A very close friend of mine operates the Grand Terrace Tractor Company and he handles many John Deere engines along with Ford-Ferguson. If he ever had a John Deere that let out a single miss-pop it would drive him to getting it right out of there yesterday-like. These John Deeres are similar to the old Rumelys about which I have been carping all this time.

At the time I was working for Case at Racine, the good old stack-draft heavy girls were just beginning to move over for the high-speed lightweights, and I dreaded to see the old timers go, for they certainly never wore out. Some of them put on rubber would make a pretty good engine today, and have saved more than one farmer from going bankrupt through mortgaging against automobile-type tractors. The crawlers are the only boys who stayed with it!

If either cylinder should be starved through throttling, it should appear to be number 1! Actually, because of no venturi in Oil Pull mixers, either cylinder is prone to miss. Feel the exhaust manifolds if one cylinder is persistent.

Thermoil 7 HP, #M74 engine shown by Dave Herbst, of near Sacramento, Cal. at the Galt, California National Early Day Gas Engine & Tractor Association in June 1975. Dave also had a 6 HP Samson #4450 in nice running shape. Courtesy of Howard E. Shideler, 2803 E. Highway 120, Manteca, California 95336.

National Meet of EDGTA at Galt, California - The belt driven four inch rock crusher, shown by Jim Johnson of Turlock, Cal. was built by the Joshua Hendy Iron Works of San Francisco. The rock crusher was originally used to crush ore at a gold mine in Coulterville. At the other end of the belt is Gary Crows, Sterling Gas Engine. Courtesy of Howard E. Shideler, 2803 E. Highway 120, Manteca, California 95336.

40 HP Superior gas engine, #40101. This engine has a Dixie #235 magneto, McCord lubricator, side shaft and flyball governor. Shown at National EDGTA Show at Galt, California by Norman Taunton. Courtesy of Howard E. Shideler, 2803 E. Highway 120, Manteca, California 95336.

An Alamo 2-1/2 HP, 500 R.P.M. Percy Goesch and Hank Barboza in the background are concentrating on solving the problems of the world, or at least of Branch 6. Courtesy of Howard E. Shideler, 2803 E. Highway 120, Manteca, California 95336

Lots of belts in action at Galt, Cal. June National Show of EDGTA. This is doing double duty with a grinder at one end and pump jack driven by Monitor 1-1/4 HP, 500 R.P.M., #24216. Shown by Glee C. Berry, Salinas, California. Courtesy of Howard E. Shideler, 2803 E. Highway 120, Manteca, California 95336.

Pictured is Lester [Silver King] Rosenthal on his 1939 Silver King tractor. In the winter and spring of 74-75, he completely overhauled and restored this tractor to mint condition. Courtesy of Larry Schuknecht, 5408 Genesee Street, Lancaster, New York 14086.

Lester Rosenthal and his son, Bruce, starting a 4 HP headless Witte engine. Courtesy of Larry Schuknecht, 5408 Genesee Street, Lancaster, New York 14086.

80 HP, 150 R.P.M., Serial #913, Bessemer gas engine manufactured in Grove City, Pennsylvania, owned and shown by Bottimore Ranch, Herald, California. 16' bore by 20' stroke. 4022 cubic inch displacement. This is a real show piece that formerly worked in a brick and tile plant in Coffeyville, Kansas. This engine starts on 120 lb. pressure. [At National EDGTA show at Galt, California in June 1975. Courtesy of Howard E. Shideler, 2803 E. Highway 120, Manteca, California 95336.

Cliff Hardy of Woodland, California always comes up with some real smooth running showy engines, but this is the best yet. This is a 16 HP Standard marine gas engine that was formerly owned by the Oakland Telephone Co. It was a lobby display and kept for emergency power. An unusual feature is the electric starter by German Bosch, also has Schebler carburetor, McCord oiler, lots of polished brass and nickel plated parts. In addition to showing at all gas engine meets, Cliff also exhibits at most Northern California Fairs. He never gets tired of showing his engines, at least he hasn't admitted it yet. EDGTA show in June at Galt. Courtesy of Howard E. Shideler, 2803 E. Highway 120, Manteca, California 95336.

Monitor Type H.J., 8 HP, 350 R.P.M. #19856, shown by Harry Hurlburt, 10653 Ambassador Drive, Rancho Cordova, California. The belt driven pump is a Gould positive pressure pump that was found on the Pavia Ranch at Diamond Springs, California. The entire outfit is painted blue, so it really looks good and sounds wonderful. EDGTA Show at Galt. Courtesy of Howard E. Shideler, 2803 E. Highway 120, Manteca California 95336.

My three 'Keller' engines I have restored. They are 1-1/2, 3 and 5 HP. The engines were manufactured from 1908 to 1919 by the Bloomer Mfg. Co., Bloomer, Wisconsin. While restoring the engines I found the original color under the brass name plate and was relieved to find out that they were not green in color, but a nice shade of maroon. I would like to correspond with anyone having 'Keller' engines, as there aren't too many of them around here, even though they were made about fifteen miles from here. I have been collecting gas engines about four years and I really enjoy G.E.M. Courtesy of Thomas W. Enderson, Route 1, Jim Falls, Wisconsin 54748.

Some engines on truck bed- 1. t. r. 12 HP Witte Diesel, 7 HP Ward's Sattley, 7 HP Galloway, 1-1/2 HP Little Jumbo, 1-1/2 HP I.H.C. Courtesy of Myron Achterhof, Hammond, Wisconsin 54015.

My 20 HP Cushman, Serial Number 344, purchased new in 1912. Lots of power for sawing wood.

Engines 1. to r. - 3 HP Fuller & Johnson, 1 HP Tom Thumb and a 4 HP Fuller & Johnson.