'39 B - Main Bearing Torque Values?

'39 B - SN 75600

Are there torque values for the crankshaft left and right main bearing bolts?

Can't find any in the service manual.

I just used a standard bolt torque chart and went by size and use grade 5 . Hard to get anything on those bolts but a box wrench too so I mainly go by feel.

Thanks Mike. I know what you mean about getting a torque wrench into these areas.

I wonder why Deere didn't give values on critical parts such as the main bearing housings, etc.

Ken

Hi Ken,

Our late friend Duane Larson discussed the lack of published torque values for Deere Tractors at one of his GOG workshops. (You were probably a little too busy to catch his comments regarding published torque values....)

As I recall, Duane felt that Deere was reluctant to publish torque values because doing so would violate Deere's penchant for advertising the simplicity and the ease of working on Deere two-cylinder tractors - and calling for the use of a specialized tool that the farmer of that day didn't have would be an admission that working on his John Deere tractor was beyond the capability of the average farmer.

Duane's research indicated that the first published discussions regarding fastener torques was found in FSB 147 (May 14, 1944) in which Deere advised torques for specific head stud diameters, and showed an illustration of a dial-type torque wrench affixed to a head stud nut. Deere call it a "tension wrench", and the introduction read as follows:

"John-Deere Dealers who are endeavoring to prolong the service life of cylinder head gaskets and avoid undue breakage of studs and an occasional cylinder block, are asking for the tension recommendations of cylinder head nuts on John Deere tractors."

Duane felt that this demand (dealers asking for tension recommendations) was likely prompted by WWII actions and military equipment that required specific torques, he assumed that mechanics with such experience would demand specifications for tractors, as well.