Make sure the foot pedal is returning all the way back, if dirt and mud holds it slightly off idle and auto idle will not engage. You can also recalibrate the foot throttle by holding the auto idle button until FOOT is displayed, at that time push pedal to floor and let off. Machine will code...
You will also need to swap front cover and change over governor springs. The governor linkage may not have a hole for the start spring to attach to front cover and will need to be drilled. Most reefer engines have the dipstick in the oil pan and not the block. You will need to drill the block...
With both the 5v sensor code and lap bar sensor code is a sign the Gateway controller has an internal failure. This is a common issue that ive seen many times. You will need to replace the gateway and have it programmed by your dealer.
If it's a flow thru system I strongly advise not running the return thru the case drain. You do not want high pressure on that circuit as it could damage other hydraulic components. I'm not familiar the the boss plow but most flow thru systems will act like that if the flow is in reverse direction.
Being a single action cylinder, I assume you are dead heading the aux circuit to maintain position of the plow witch opens main relief valve. With main relief open you will not have enough pressure to operate lift and tilt. Is it possible to change to double action cylinder?
The case drain port is not designed to handle the return flow of the auxiliaries. You need to plum the return line to the top port of the auxiliary block. See if that helps.
The accelerometer is the knock sensors on the back (door side) of the engine block. Over torqued sensors can cause this code. Loosen sensors and re-torque to 16 ft-lbs. Also check the connections to both knock sensors. it is possible one of the sensors could be bad but very rare.
T76 is to new, I would advise waiting a little longer. The T650 is by far the very best machine Bobcat makes, plenty of power and no DEF to mess with. No way I would touch a CAT with ASV. The T650 will be the most reliable of the three for sure.
It can be done either way but I prefer to pull the whole unit. The rear engine mounts are difficult to get to but not impossible. Also depends on the options, such as high flow, power bobtach, and enclosed cab with AC. The more options the less likely I pull complete unit.
You should be able to change the connections but usually they wont run in reverse if it is a multifunction unit, meaning using electric over hydraulic for chute rotate and deflector tilt. What make blower is it and do use the electrical 7 pin connection?
Charge pressure is provided by the gear pump and maintained by the charge relief in the hydrostatic pump case. Is lift and tilt working good? if you take either lift or tilt maxed out in either direction over main relief will the engine lower in RPM's slightly? Check main drive belt and...
When you say case drain, did you plumb the return to the actual small middle case drain fitting on the manifold block, if your machine has a block with case drain, or to the larger male fitting on the manifold.