MTV 1084 w/MHC Hay Feeding Truck Conversion

[cowhock35]

No tcase output for pto. Just the ring gear/pto port on the side of the trans. Electric hyd usually has a duty cycle.

Really trying to avoid any extra hydraulic addition saying as I have the pto already. Only one fairly small motor on the feeder needs to run while driving and theoretically it could be an electric motor, it is mounted directly over the batteries anyway. Either that or electric/hydraulic or an engine driven hydraulic pump, either of which we use on the standard bale feeding pickups.

I guess I don't really understand how creeping at an idle could damage the pto or transmission, especially if there isn't significant load on the hydraulics. I have dealt extensively with running and operating hydraulic systems and PTOs, but never installing a PTO on a system and always on manual transmissions so there might be something that I'm just not understanding here. I don't need to shift while it operates, and I don't need to run the PTO at a specific RPM. I would probably want to lock the trans into first gear so it wouldn't shift every time I operated the PTO.

 

[Suprman]

First gear is low range the truck starts in second. If you can get the truck into gear somehow and stay in that gear and run the pto all at idle it may work. I didnt say that would cause damage. I said the trans control prevents shifting above idle rpm to prevent damage and that the pto is intended to run at a higher rpm.

 

[snowtrac nome]

The problem has to do with the function of the pto. Te torque converter must be in lockup for the pto to function properly, on the 3070 transmissions once the trans hits 3rd the trans goes to lock up all the way to 7 th . In the lower gears with the t/c not locked up you will build heat faster than the cooling system cant dissipate it. go with a crank shaft driven pump or stack asecond pump off the accessory drive like the a-3 duce.

 

[cowhock35]

So the t case is locked up when it’s in neutral? If it’s a heat issue, the process of feeding a bale will be very low flow and take probably 1-2 minutes. Would that short amount of time let me Bypass potential overheating problems?

Also went in and probed the ecm power wires and I found odd things. Pin 2 (battery pos) to pin 9 (ground) was only about half a volt. Pin 11 (battery pos) to pin 18 (ground) was 12v, and pin 9 to pin 12 (ignition) was 24v.

I don’t really know why there are 2 power and ground wires (which are different from the chassis ground I guess) but I would imagine I should have 24v down both of them.

 

[cowhock35]

So, a few updates on it. I toasted the trans ECU, sent it off to Transmission Instruments who fixed it beautifully for me and replaced the panel and screen which were in poor condition. Shifts great now.
Tried an electric/hydraulic, couldn't get the flow I was hoping for. 2 GPM was the only affordable system an its just not fast enough. To get more hydraulic power I see a few options, either find a way to get a clutch pump under the hood which is very space limited, piggyback a second electric pump in parallel, which would be clumsy and still power limited, but cheap and easy, install a front shaft PTO, or get the PTO to run while in gear.
From my research, the PTOs on these trucks are not the hot-shift types, which require a clutch pack so they can be activated while running. These are a lot more expensive, but honestly not that much more than a clutch pump would be. 1500 new and 1000 used or so. I have read about people having army trucks with these on them, but haven't talked to anyone with actual experience or knowledge about the install. I'm thinking I'll call an Allison dealer tomorrow and see if they have any insight?
Other than this, the project is coming along pretty well. Having to do some fiddling with the hydraulics because with 3 separate valve bodies I have to close 2 of them off whenever I run the 3rd so the bypasses don't allow fluid to cycle. Oddly enough, even with my third block, both of the original blocks seem to have open centers and if I deadhead an outrigger to close off the lower block the crane will run about twice as fast. I'm thinking I'll use the integrated shutoff solenoid to the top block to shut it down when I use my auxillary block and use a ball valve to keep the lower block off since its rarely used anyway with mast and outriggers on it. I got a 16 channel remote control relay block to turn everything into remotely controlled which has been awesome.

Still battling the hard start but will try turning fuel up. Part of my issue is there is just no crank power in the batteries. 10 seconds is maybe all you get. I took them off and fully charged them and they tested ok on my load meter but somehow they must be bad. Some of the grounds will get hot enough to burn you in only 10 seconds of cranking, which doesn't say good things about the cabling but shouldn't totally drain your crank power I wouldn't think.