Primos75 wrote: I wonder if anyone's tried this or if it can be done. I've had no luck looking up the part number. Salvage yard near me would pull one of an old machine for $300 but I dont know about that. Seems a little high. My buddy has one on a non running 6g but it would be a bear to get to.

This is a screenshot of the Barnes fuel pump for the 2-71 Detroit Diesel from the HD5 parts manual:

That is a left hand pump shown in the photo.

The red pump is from a 6V-92TA, the green pump from an 8V-71, and the yellow pump in back is from a 3-53. All are Detroit engines I currently own. The two front pumps are left hand, the yellow rear pump is right hand. You can ascertain this by looking at the venting ports facing up and are seen on the two front pumps. The relief valves are on the left with the front pumps, on the right with the yellow rear pump in the photo. The wrench on the right is one I bent up to access hidden fasteners and worked well. 

Primos75 wrote: Very similar to the wet clutch pump i posted. Does anyone know what the psi and gph the pump should have for the clutch? The manual says the filter has a bypass at something like 18psi I think.

The 2-71 typically runs around 60 PSI fuel pressure. I have no idea what the requirements are for your application

I have never seen the pump AC used. I have replaced a pump in the wet clutch on a Cat 9u D6, it is smaller than the DD fuel pump. But no idea of flow or PSI it operated at.

I know of a late AC HD 11 ag cat the owner had a pump special built to replace the AC pump. This was 20 years ago and was 2000 to 3000 dollars. So adapting a similar pump looks to be a cheaper way to go.

Primos75 wrote: Very similar to the wet clutch pump i posted. Does anyone know what the psi and gph the pump should have for the clutch? The manual says the filter has a bypass at something like 18psi I think.

I did find some specs on the hydraulic pump for the HD6 steering clutches; it has two sections, one section for each side. It did not give a specification for the pressure but did state that "Hydraulicsystem pressure is non-adjustable; system is designed with proper "built-in" operating pressure to disengage steering clutches"."

The manual does state that each set of gears has 1.5 gallons per minute capacity @1200 rpm.

I would guess that if you found a pump capable of ~2+ GPM and started out at ~20 PSI you could turn up the pressure until it could cycle the clutch it should work.

The main clutch pump bolts onto the rear of that behind cover 13, so it is in fact a triple section pump.

Master clutch oil pump is only a circulating lube pump. And oil pressure is only around 20 psi.  I know this because ive seen some late 40M series HD6 that had a clutch pressure gauge fitted in the dash.

Also the drive coupling used on all the pumps is the same 2 fingered 5/16 square coupling used on the GM, as that is what some of us have bought when the pump couplings wear out.   The triple section pumps can wear out the couplings if people run too heavier oil in the HD6E tractors

Ahhh... now we are getting somewhere!

Thanks for the input

I'm not near our AC Forty Five grader or the books 

IIRC the only hydraulic pump on them was for power steering.

I might get a chance to look tomorrow.

Incidentally Australian versions of that grader had model number "524/****" and the pump was Hydreco

Apparently I misunderstood the function of the pump; it really doesn't assist in actuating the clutch, but rather is only to facilitate circulating the oil for the purpose of filtering and as an aid to cooling?