Inform Me Please

What does stage 2 for H's & m's mean ?

Basically what it was, they had a live hyd system from the factory,that was driven off the timing gears.

IH upgraded H and M's in stages to get to models 300 and 400. As Fastfarmall said stage 2 was addition of live hydraulics and more horsepower and a few other things. Stage 3 added a torque amplifier and you could have a live PTO on a M but never made it to the H. Stage 4 was a model 300 (previously H) and 400 (previously M).

Name become common later for super H and M tractors equipped with chassis changes compared to previous models of supers. Changes were made for use when equipped for a engine driven hydraulic pump and system compared to a transmission counter shaft driven pump on previous versions. After the chassis changes a countershaft pump could still be used on a SM but not on a SH. Stage 2 SH was equipped with no hydraulic or engine driven pump. Don't think IH used the stage 1 or 2 name. Both SH and SM had the tractor center housings changed at stage 2. SH stage 2 wasn't equipped to mount a countershaft driven hydraulic unit. SH stage 2 moved the starter location and number of mounting bolts to locate a hydraulic unit on top right of housing. SM used a housing about like previous models but the starter mounting added another bolt and was also changed even for the diesels that already had 3 bolt starter mounting. Gas, diesel and later SW6 ended up using the same housings. Hydraulic unit for a engine driven system if equipped was located under the fuel tank and used as the rear fuel tank support. Changes to both tractors moved the battery location to under the operators seat. Some other smaller chassis changes were made.

I am pretty sure the whole "stage" system was NEVER used by IH during the manufacture of the tractors. It was made up later by collectors to make it easier to refer to the different stages of evolution that the tractors went through.

My take on it is that the execs at IH were not sure how the old school farmers, who were barely used to using tractors in place of mules and horses, would react to "modern" conveniences like live hydraulics, live PTO, and a 2-speed powershift system. I mean we see it even now, something new comes out and the grumpy old phart comes out in everyone, "Ain't gonna be any good. Too many new fangled thingies on it. It will be in the junkyard in 20 years while my XYZ is still going strong!" Believe it or not, there were farmers saying that about the original M, the 806, 71XX series Magnums... when they came out, yet today these are regarded as some of the best of all time.

So they introduced the technology in small easy to digest bites, wrapped in a package that the farmers were all familiar with. Little bit, little bit more, little bit more, slight change to the packaging, another slight change to the packaging, now lets put a 6-cylinder engine in it... That was the attitude of the time.

They made super H's, and super M's. During the production of these, they added even more features at some point. So people started referring to the earlier ones as Stage 1. And the later ones with even more features as Stage 2.
This did not apply to the regular H's and M's. They were slightly improved during production. But no drastic changes during that time.