8640

[BradWi]

I am looking at an 8640 with 9000 hours on it (asking13k) just to work ground on a couple hundred acres,time is an issue for us so hence the need for a big tractor.What is the good bad and ugly on these? I ran an 8430 for years for the neighbor and felt that it was a decent rig although the powertrain left plenty of room for improvement.any thoughts would be appreciated

 

[4020guru]

Does that 8640 happen to be in Wisconsin ?

 

[NY 986]

There is a serial number break around the 1980 model year for the engine going from a camshaft driven oil pump to a crankshaft driven oil pump. The crankshaft oil pump is superior and far less prone to failure. The engines did not like stress from the frame like severe oscillation on the axle to cross a ditch. Make sure the axle bearings have been lubed. If the seller is willing to go along oil and coolant testing is a good idea. If well taken care of they are a good tractor. Fuel economy is typical for the day better than something from the late 1960's but not as good as something a dozen or so years old. I know of a low houred 8640 near me that has low hours but has been neglected. There is another one coming up at auction but my buying focus is elsewhere for this year.

 

[BradWi]

yes, stoughton area

 

[4020guru]

I just so happened to look at that tractor last weekend. It is what the seller says it is .

 

[4020guru]

So the late model 8640s had the crank driven oil pump ?

 

[NY 986]

Yes. At the time in 1980 all 40 series tractors with either the 6619 or 6466 engines received this upgrade.