SC Fan Parts Don't Fit 200

The fan bering on my 200 went out. (It was low on grease.) I should have looked before I bolted on the replacement! First the generator drive pulley was larger on the 200 than on the older letter series tractors (at least the ones I have seen). So I swapped out the pully but kept the old fan. The pitch on the old fan was greater so it would not pass the retaining nut on the water pump. Dark came with me removing the fan for the third time. I am trying to switch out the fan without removing the spindle, the belts, and the pully and it looks like I will get it done. It may be a good thing I am not getting paid to do this. I may be an ag-engineer, but I will never claim to be a mechanic!

LMack: A lot of us make that statement quite often in the run of a year, "It's good I'm not getting paid to do this," My favourite is, "I made $0.10 per hour refurbishing the old tractor."

I am interested to see this as I have a fan from a C-123 engine, that I had hoped would be a stand by for my SA - C-113 as well as 130 - C-123.

Another observation I make, is just maybe the older fan with sharper pitch came from a thermosyphon tractor. The fan on a thermosyphon wouldn't need to pass the pump shaft. I must have a look at my SA and 130, I never compared fans before, never had both off at same time. It makes sence the thermosyphon would use a more agressive fan.

LMack: I just took a stroll out to my shop, my thermosyphon SA definitely has a more agressive fan blade pitch than my water pump 130. Could be the reason why we ocasionally see folks having troube with thermosyphon cooling, just maybe some of them have the wrong fan.

I realize the SC your fan came from would have a water pump. Could the fan have come from an A, B, C or SA? Just my observation after having looked. Anyhow, thanks for the heads up, maybe I'll get up to $0.50 per hour on my fan switch, if and when it happens.

Hello Hugh: I might not agree that the newer fans with water pump would have less pitch. With a thermostat the water flow is stopped untill it is hot enough and then released and forced quicker through the cooling fins and back into the block in a shorter time... therefore needing a faster air flow for the shorter time that the hotter water was being cooled. I'd take the odds that more pitch for more air flow was for the later water pump and thermostat controlled system.. But the best answer is the parts number for early and very late units.. The later 123's were pumping more HP so cooling needs probably higher needing more pitch on fan also? Take care.. Sorta fun to try and guess why a certain thing was done.. ag

Agpilot: I don't pretend to have all the answers, however I know my SA and 130 are original. Super A being C-113 thermosyphon, and 130 being C-123 with water pump and thermostat. Super A is the one with the more agressive pitch. Remember the agressive pitch blades don't have to clear the water pump shaft on thremosyphon tractors.

Now, LMack found two different size generator drive pulleys, maybe Maybe the fan driven pulley is different as well. He also found the more agressive fan blades wouldn't clear the water pump shaft.

By the way I don't buy your argument that water pump with thermostat would require the more agressive fan, that pump starts circulating coolant soon as the thermostat opens at 160-180F. Thermosyphon runs very close to 212F. You shut one down from heavy work and within seconds you hear boiling in the rad. I've run these ever since new, and they always worked that way. Let my SA idle for 2 min. and you'll not hear any boiling. I never hear my 130 or 140 rad boiling no matter how hot or how long they've been working full out. For that reason, I believe thermosyphon requires the more agressive fan.

Hi again Hugh: It may have been a simple need to clear the water pump and not much to do with any cooling factors required by the engine.
By the way, your comment:"You shut one down from heavy work and within seconds you hear boiling in the rad. I've run these ever since new, and they always worked that way." ... Hugh,you might be better off to allow some running time to cool off from heavy work or at least that seems to be a common suggestion. We always let our 1941 MD cool off after all heavy work from two family farms plus custom work for over a decade and never cracked the head. Cooling off after heavy work makes good common sence... for a man or machine... (adding a cold beer on extra hot day helps too)
I was just adding another possibility.. Bottom line,use whatever the factory sez. ag

Agpilot: Did you notice, I SAID IF I SHUT IT DOWN HOT. No where did I indicate I do that on a regular basis. If you can't comprehend that, perhaps you don't understand the fan use.

Since the thermosyphon system depends entirely on the difference in density of coolant to circulate, and the difference in density is a result of the difference in temperature, it would make sense that more air flow would be needed to keep the engine cool. A thermostat system can operate with a much higher coolant inlet temperature since the pump insures circulation.

Sounds like an engineers answer to me. Thanks!!!

I have three tractors here, a B, an SC, and a 200. The B has no water pump and an agressive fan. The size of the fan pully seems to be common. The size of the generator drive on both the B and the SC was common and about 2.5-inches. The SC has a water pump and a less agressive fan. The size of the generator drive pully beside the fan pully is larger in diameter than the fan belt pully (about 4-inches). I did get the fan on without pulling the fan shaft.

1) You should be using oil, not grease. If you use grease you might as well leave it dry because it will never get to the bearing.

2) The Super C (and earlier models) could have either of 2 brands of fan, Service Products or Schwitzer-Cummins. The 200 and later were all Schwitzer-Cummins. I assume you are not mixing parts between the 2 brands. Same precaution applies when looking at differences in the fan shape or pitch, it could be the difference beween brands.

3) The Super C and 200 both had the C-123 engine with a water pump so all the conjecture about different fan requirements for water pump or not are irrelevent to the original question.

4) The useful Parts Catalog for this case is for the Farmall C, as the water pump was an option. It shows both the Service Products and Schwitzer-Cummins fan assemblies. In the case of the Schwitzer-Cummins, they show 2 part numbers for the fan itself:
70212D with no water pump
70214D with water pump
Since the same Service Products fan was used with or without a water pump, it doesn't look like any reengineering of fan capacity was done when a water pump was added. The second fan for the Schwitzer-Cummins was probably just due to interference with the pump assembly itself.

You all have diffently got my attention. Several years ago i replaced the fan hub on my C. I ended up getting the replacement part form the dealer. I never did compare the dia difference on the pulleys till this year. Last time i ran the C, it overheated due to a radiator leak-no water pump. After i removed everything and saw the size difference and compared it to my B and A, the gen pulley is way bigger. I allways had trouble getting it to charge as it would burn out the reg and eventualy would fried the genny. I even sent BobM many emails about it back in sept. Anyway I did change out the fan hub to the orginal size, guessing that will take care of my problem as im thinking it was spinny the genny to fast and giving it a hard charge

Jim: I'm not sure you resolved this. What serial numbers were the last Service Products fans used, both SA and SC. You are presenting us with a water pump fan and non water pump fan for the Schwitzer-Cummins. Why would one brand do all yet the other brand required two separate fans.

Looking at my SA fan the pitch is much more agressive than 130 and 140. Driving the three tractors I quite regularly feel the breeze from SA fan. Very rarely have I ever got a breeze from 130 or 140 fan. Now, I realize the 140 is a whole different setup. Given the fact that SA sheet metal is 2" closer to chassis, I would expect that to block air flow somewhat to operator platform. There could also be another factor, my Super A is one of the roughly 20,000 SA with pressurized thermosyphon.

Not sure I signed up for researching the whole history of fans.

Two different brands of fan wouldn't necessarily be expected to run in exactly the same place -- one could have been a little closer to the radiator and the other a little closer to the engine. The one closer to the engine needed to be modified for a water pump and the other didn't. Not that improbable.

According to the parts CD:
On the Super C, Service Products fans were used intermittently on tractors with serial FC-170825 to 176309.
On the Super A, the Service Products story is more complicated because of some changes to the fan assembly so I'm not going to go through it. The Schwitzer-Cummins fan changed to the Super C/200 version when they went from the Super A to the Super A1. Evidently the Service Products was not used on the Super A1.

LMack,If you put on a new style hub(sealed bearing) just tweak the fan blade with a crescent wrench,when I replaced mine I tried to shim it, get a different one etc. I finally saw that it only hit on two blades so I just barley bent the blades for clearance,that was 7 years ago.