question for Charlie Biler

[sunnen]

I want to make up a U for pulling get about 80 hp. I want to use a G crank and M5 jugs. I dont have a stack of money to spend. But I found some jugs cast number 10A10248 and heads 10A23134 I think thier from a M5. I seen you post with some Knowledge about these things and not just theory. what heads should i use whats the cast # for a G crank.
Adam 810 230 6711

 

[Anonymous-0]

Those are diesel blocks and heads. You need 10A22196 blocks or 10A15154 blocks. You problally want 10A4210 heads. If the parts you have are good they will trade for the parts you need. The forging # for a G crank is LE401.

 

[Dieselbear]

I'd be itnerested in the diesel jugs and heads if you want to sell them. Let me know.
Thanks, Glenn 301-874-2146

 

[Charlie Biler x]

sunnen,
I agree with mmmmmmmmmm that the crank forging number for a six inch 403 crank is LE-401. 10A4210 heads are what is normally sitting on a later UB and are the mildest thing that you can get.

Personally I would not start building from a pile of parts. For me the cheapest way out with the most horsepower is to go looking for a worn out 403 power plant engine. Piecing together gets mighty expensive and a worn out 403 engine normally goes for half of what the parts will cost.

After you have the pieces for your transplant; you have to just clean up some wear and do a swap of parts. After one nights work you will wind up with a nice farm ready U that will have more horses, and way more low end torque, than you can get hooked to the ground. Around here the lineup at most pulling contests looks like a Minneapolis-Moline convention that are featuring U tractors. All are running 403 engines with slight modifications. Even running low altitude heads is not a problem when the pistons are coming up beyond the cylinder deck and one pays attention to proper tuning of the ignition and fuel.

In these parts they limit maximum RPMs and there is always some sort of speed limit. Speed limits are death to short strokers and trick cams mean that you can never get any torque because the bottom end of the power curve is suddenly gone. Even if you leave everything alone, except the bore, going to a larger diameter piston has turned a nice 283 engine with a 0.85 stroke ratio into a 0.925 ratio racer car with those 4.625" pistons. A nice stock 403 gives a stroke ratio of 0.771 and good aluminum pistons fed good fuel with moderate compression increase mean real power with the ability to use the throttle like you have an automatic. As you approach the magic 1.0 ratio the RPMs have to go up to make up for the loss of torque at that RPM.

If you exceed 1.0 stroke ratio , the engine is suddenly a chain saw engine and it takes a never ending increase of RPMs to keep things moving. Centrifugal force starts tearing at the crankcase and the weight of the pistons eats horsepower as their mass must keep changing direction ever faster. Ever wonder why those old stock FE engines would pull like there was dynamite in the cylinders? With a stroke ratio of 0.75 the ball and chain 4.5 inch iron pistons could still haul the mail. That is why a farm tractor with the lower stroke ratio can slack off and glide over a soft spot on the track and still turn in tire burning power at the flick of the throttle. Drop in some forged aluminum pistons, that do not have those quarter inch rings, and the old Twin City engines run like tricked out pulling tractors.

I am not saying to go one direction. More cubes always mean more power. I just advise that a person thinks through where he wants to go and that they map out a good road. If most of the pullers I see would learn to properly set a carb and learn how to read plugs; they would see a great deal more performance from forty bucks worth of investment. The old timers used a baker dyno fan to tune their steam tractors. They understood that valve timing, fuel to draft ratio, and such meant maximum power with little, to no, investment. A lot of today's tractor mechanics do not even tune their engines before a pull. Maybe they should get out grandpa's wind dyno and set their engine for maximum performance, instead of maximum smoke.

Remember to have fun.
Charlie

 

[Molineone]

I like your answer. I too am currently building a "big block" U. I was trying to find some oversize pistons, like .090 or .125 over for some 336 jugs I have (It is already punched out .060), but I am having a really difficult time doing so. So I am considering tossing in a taller crank and jugs, and just making it a 403. It sounds like you are almost discouraging this setup. I think your opinions sound like valid ones, and I would like to learn more if you have any other advice. Thanks.

 

[JS BOATS]

We did simular what you're thinking back in 1982.We took m-5 blocks bored out to 4 7-8 used a G crank M-5 rods sized them to G crank and used 401 GM piston shaved them flat and used base block gaskets to get right compression we needed.I think we had 7 gaskets.Ran 10A4232 heads on propane and turned it about 3500RPM.It was one tough UB and is still running in Illinois.It was alot of trial and error but we did it for not much money.One of the toughest thing to do with the UB was to get it balanced such a short wheelbase.Side weight brackets made all the differance. We ended up with 448 cubes Good luck I like to see Molines at the pulls

 

[Charlie Biler x]

Molineone,
Don't get me wrong. I have a UTU in the shed with 4.625" skinny ring Gould pistons and a stock five inch stroke. The pistons pop out above the cylinder blocks and she will really make the tires spin with those 336 cubes, especially since she breathes through a tricked M5 manifold and has a seventy thousand volt ignition. I have had her running for more than twenty years. I will never tear her apart because she is a great tractor to use around home. With a full platform, power steering, and all the trimmings one can imagine, she earns her keep. I just know that a U with 4.25" pistons and a six inch crank would tear my 4.625" bore U to pieces. I have operated 340 cube Moline motors with those 4.25" pistons. After I handled one, I realized why the old Twin City engines performed so well. That 0.708 stroke ratio makes it happen right now.

I cut teeth on a FTA with a GE 403 engine. I operated that FTA when I could engage the crank at the three o'clock position and use it as a perch to dump water into the radiator. Dad, or one of my uncles, had to crank it for me. There was no starter so I parked it on a hill at shutdown. I damaged a lot of equipment because it had the power to destroy things in high gear, very quickly. Drag plows, in those days, did not have kickouts. I bent a few beams and broke more than my allotment of points and shares. We will not go into what happened to some other things. Did I mention that I learned to torch, forge, fabricate, and weld too?

In later years I finally was able to experience a 403 without those old iron pistons. I still have those Twin City stamped cast iron pistons to hold down my notes. Good thing The kid I was never had aluminum pistons. When I started playing with 'Big Power' series engines and those stock 4.75" and 4.8125" pistons to spin a six inch crank; I was spoiled rotten. A tractor that can work the field and turn in that much power still makes me tingle. That is why I am burning the midnight oil to bring back those #10P2962 'Big Power' pistons in something forged. I still have some of those pistons in the box, from the original manufacturer, but I want to taste the forged flavor.

Everything has its place and, like I said before, more cubes mean more horsepower. I also know that stroke means torque. Stroke length means nothing. It is the ratio of stroke to bore that determines the torque curve. My teachers also taught me that when you increase compression ratio, you had better jump the RPMs in a linear ratio by about eighty percent of the RPM increase. The fuel had better start getting a longer burn curve (octane) too or nothing good will come.

I am not discouraging anyone from boring out a U. I am not discouraging anyone from building a 403 from pieces. I have done both. I just know it takes a lot of small pieces to do the deed. I wish I had a dollar every time some guy asked me how to use U pushrods in his new 403 engine. I have also turned a lot of G starter noses down and switched drives for guys that discovered, it takes a lot of watts to turn over a high compression 436 cube Moline engine. A U starter needs a lot of expensive work to turn over that much engine. A good surgeon knows that an easy transplant means having the donor on the next table.

Make sure you know what you are going after. Know where you are going to get what you want. Make sure you know how to get there. Finally; check your wallet. I have a wise friend that always tells us,"you can't afford the cheap stuff. It costs too much".

Happy motoring.
Charlie

 

[Charlie Biler x]

JS Boats,
I do enjoy such tales from the dark side. I have spent a lot of hours hunched over a lathe and leaning on a mill to make things fit, in places they should not go. I bet those M5 blocks looked like tissue paper on the bottom of the cylinder liners.

I personally take a slab of steel and fly cut it down to create 'thick crankcase gaskets'. Don't you just love it when the piston is a hare too close to the head and you have yet to figure out how to add metal to that shim? Those water jet machines now make shim plates faster than I could CAD them out. I worked in industry for years and now my manual mill, at home, seems like I am holding something between my toes and I am using a file on it.

Did you balance the pistons and rods by scale, or did you have some other way to keep things matched? It takes forever to get all of them the same and I am always looking for something easier.

As for balance of the tractor; My standard method is to pile everything on the front and change the hitch length with a series of holes where the drawbar mates to the rear end. My luck is always that the front end points skyward and I have the hitch to the shortest allowable length to axle centerline.
Charlie

 

[JS BOATS]

I was passing this information on to sunnen not Charlie Biler.Sir this is not tales from the dark side.We built this engine from ideas we got from Marlin Holzer.Marlin built a 6 cylinder the same way we built the 4 cylinder.I'm sure Moline pullers all heard of Marlin Holzer and his mechanic Wilbert Kerchner.My uncle farmed next to Bill Newlon who also gave me advice.So if this is tales from the dark side then maybe Marlin,Wilbert,and Bill never heard of Minneapolis-Moline!!!!!!

 

[Molineone]

You are wise man Charlie. Thanks.

 

[sunnen]

Thank you Charlie. sunnen