HD10B Crawler Tractor questions

Welcome,

Allis HD10 was only produced until 1949 and used the general motors 4-71 two stroke engine.  it has only 1 top roller, the outboard bearing holder is a different design and uses 2 oil bath filters with 2 intakes. the dash is quiet a bit different as well.  its hard to tell with all the added hydraulic components on the front but it looks to me like it is not an HD10 AC

Edited by CAL(KS) - 19 Dec 2018 at 2:40pm

That looks more like a HD 9 than 10. The 9 was the replacement for the 10 in the line up and then they built the HD 11 latter yet. This is a AC built tractor not the latter Fiat FD 10, a different animal in all ways. The smaller AC tractors were built in 2 widths the narrow was a HD x A and the wider was a HD x B. I was not aware that a model as large as HD 10 had a A model so I did not think they would put the B on. But I never work on a HD 10 only drove one a very little bit 50 years ago. The track frame with 2 carrier rollers is like HD9 as well as the fuel tank and deck from what I see around the brush guard. HD 9 will have a Rockford clutch unless like HD 5's some had another brand as well. Probably have to have a truck clutch shop put new lining on the old disc.

Ray54 wrote: Another thing the GM 4-71 engines changed from what is called a high block on the 10. The 9's were a newer design and a head from the late V8 -71 could be used with extra valves to up the HP of the 9's. Cal are you enough of a GM guy to explain the differences more?

  I am not.  Only tidbit im aware of in the 4-71N  designation made more power,  maby were talking the same thing here.  Now that you mention HD9.  I think you are correct.  The blade trunions were moved foreward with the 9, 15 and 19 crawlers Unlike on the 10, the trunion is located at the outboard bearing.  This outboard bearing looks similar to HD15 style (which we have)  and tells me double reduction final drives.  Introduced on HD6, 9 and 15.  The dash is definatley not HD10 but could be HD9 if similar to 15.  Intake and exhaust arrangement are same as HD9 photos on the net.   The shift pattern should be forward speeds on front side with high low and reverse speeds to the back with R1, R2, and R3 respectively moving away from driver.  HD10  used old gated style and was patterened like a truck trans, not quick forward and back shift of later tractors.  

Edited by CAL(KS) - 20 Dec 2018 at 8:40am

Looks like a HD9 to me. The picture of the deck seals the deal to me. Seeing the tag is on with screws it only takes a minute to change, but why. A Detroit Diesel 4-71 commonly refereed to as a screamer.  I cannot tell you the RPM ,but compared to my D6 of the same vintage that runs 1600, you can see were many would have said 2200 is crazy back in the day.

I bet that's close to the max, in that range

It seems like some of you fellows may be able to answer some questions for me for this HD9B.   I figured out why the owner had a HD11 service manual.   The HD9 uses the same clutch parts and other parts as the HD11.   Aside from the HD11 being a lasrger crawler it also uses the 6 cylinder diesel and the HD9 the 4 cylinder diesel.  I just received good used back plate.   I have to put flywheel back on crankshaft and  the 9/16" NF bolts (13/16" head) were very tight or just well seized from being attached for many years.  We broke them loose and thinking of using blue thread locker upon assembly.   The service manual states 95-105 ft lbs for these bolts yet that seems a little low.   My generic torque chart shows 110-180 ft lbs depending on grade.  Mechanics wire is to be threaded and twisted through all flywheel to crankshaft when attached and bolts torqued.   I was wondering if anyone here has torque specs for HD9 4 cylinder flywheel and back plate?  Or a website or business that may?