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Well, after Kent got the ball rolling on the idea of a "hybrid" tractor I decided to join in on the project idea with some of the stuff I had laying around here.  I started with a beat old 3012 that I was not afraid to sacrifice. I did not want to hack up my AC  B-110 frame till I saw whether the frame modifications would work or not, as that yellow paint seems valuable. The only Sundstrand-equipped parts machine I had was the remains of a AC 917 with the hydraulic lift. So I figured to incorporate the lift into the project as well.
I split both machines and bolted the 917 rear (including Bevel Gear Box) to the 3012 frame.  I then started the modifications by making  measurements and figuring on the placement of the hydro lever on the 3012 chassis (pic#4).

After marking locations, with a torch I cut out the bottom of the frame for the control lever linkage to fit through. I then marked and  cut out a hole for the brake rod to pass through. (pic#3). Then I welded  two short pieces of angle iron to the bottom of the frame at the front and back  of the linkage hole for stiffening and reinforcement.

Next I temporarily re-fitted the dash to the frame and marked locations for the lever quadrant, drilled holes and installed. (Pic#4a)  I then ground off the safety engagement tab on the lever and  put the lever on and put it in the neutral position. I then put the tab up by hand and clamped it on the lever in its new location (over an area on the dash where the switch could be placed from inside the frame) and marked the place on the side of the dash where the switch would go under the tabs new  location.  I then drilled the hole and welded the tab to the lever. 

Next I took off the whole upper framework. The hydraulic lift cylinder would have to be installed before I could see what clearances I had to run the lift rod and PTO.  I took the cylinder and attached it to the lift shaft and ran it back and forth manually to mark location on the frame where the rear of the cylinder would have to be mounted. This in order to get the motion and stopping points  about right.

Then I took the 917 cylinder bracket and cut the mount braces off the ends of its shaft. (pic#8) I ground the welds off and knocked the remaining shaft stubs out of the braces and ovalled the holes out. I then trimmed the shaft on the rest of the mount for position and  to fit in the tractor frame. 

I then set the braces back on the ends of the mount shaft and clamped it all in the frame with the cylinder pinned on and welded the braces back onto the mount. I then marked and drilled the two holes in each side of the frame for bolting on the cylinder mount.

With that installed I found little room for the original lift rod, so I opted for a cable. I had
to add a guide pulley to keep the cable free of rubbing the cylinder. I used a pulley from a 7000 series deck lift cable, marking and drilling another hole in the best position to accomplish the task. (pic#9)  Note that installing the cylinder and pulley required much measuring and dry fitting of pieces so they would all still fit under the dash assembly when installed.

 I also had to extend the lift bracket on the lift shaft up so the cable would clear all the other hardware during the full motion of the cylinder. I did this by cutting the cable clevis halves off the 917 lift shaft and welding them on either side of the left leg of the 3012 lift bracket on the lift shaft. (pic#9)

I really wanted to run the safety switch and engagement for the PTO on the inside of the
frame but there was absolutely no room. So, after seeing Kents PTO solution I adopted his idea. (pics#5 & #6)   I did however,  still want the safety switch in the loop. So my solution was to weld a steel tab to the PTO bracket and mount the switch in the tranny frame. (pic#7) I dry fitted everything first hand to see what angle the tab had to be welded on at (in the "off" position) then clamped and welded the tab. It seems to work pretty good. An easier solution than I had first envisioned.

Now I disassembled it all and painted the parts Ace brand "Sunset Yellow"-unfortunately now discontinued already. Following the drying of the paint (many days in cold weather) I reassembled it all back to the point I was at.   Now I had to mount the lift valve and run the hydraulic lines.

I basically used the torch to cut the frame and all around the valve out from the 917.  I then mounted it to the B-110 (this is where I started using parts off the B-110 donor) lift lever bracket. Then I used spacers to space the bracket out from the frame about 2" +/- and bolted the assembly back on where the lift lever bracket was originally. (pic#14 & #18)

There is no other way to mount the tubing but with a quality tubing bender and just taking the time to fit, bend, and re-fit till it all goes in right. I had to loosen and re-adjust the fittings on the valve several times in the process till all lined up. I also had to bend the tubes up and over the "swing" of the lift cylinder so nothing would make contact, including hoses to lines, while lifting and lowering implements.  

The hoses were the original types (albeit brand new) that the 917 used. I had to open the bend  in the hose fitting going to the rear of the cylinder so it would loop around the cylinder mount and into the fitting on the cylinder. The straight end of the hose goes and back to the front of the tractor and loops back into the appropriate fitting on the valve.

The other hose required no bending and the  straight end goes into the front of the cylinder where I replaced the 45 degree fitting on the front of the cylinder with a straight on just like at the back of the cylinder.  The curved end of that hose loops back into the appropriate fitting on the valve turned to a direction to accept it.

As you can see in Pic#10 and #11 everything is pretty tight together and required a lot of fitting and re-fitting to get it right.  I cut the hydro lift lever down and welded a threaded stud on to accept a "shift" handle. I dry fitted the pieces to a comfortable position before I  made my welds. (pics #12 & #14)

Compared to the rest of this project the wiring was a breeze. I wired it as per the 7000 series tractors of 1975 and 1976 using a starter /generator.  Everything was done as tight and as neatly as possible. (pic#16 & #17)  I installed the Accessory jumper board inside the dash assembly  (pic#15) just above the safety switch. I used one of the original holes in the side that had accommodated the Varidrive quadrant.

The engine was no big task either. I used a 1992 16HP I/C Briggs that I found in a junk 7016 behind a dealership for $100 (for the whole tractor!) I took out the standpipe/ dipstick and put a pipe plug in place. I did have to grind the top of the plug off a little to clear the tin on the tractor. Then I put a older style pan appropriate to the tractor on it, painted it, and it was ready.

The driveshaft used was the 917 shaft with the rubber coupler and  one set of 3/4" metal driveshaft spacers and a pair of the standard heavy beveled washers between the coupler and the flywheel.
I added my 4 new tires, the rears being ag type on wide AC rims, put on my custom "HB-116" decals (pic#13), and am now ready for test runs to iron the bugs out.

I would like to thank Kent Thomas for his valuable input on this project. Working at it with him was truly enjoyable.  I would also like to thank Sandy Lake Implement for quickly getting me the parts I



AC 917 Donor Tractor









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