engine replacement for b7100

[moulinjegu]

Hi there, so good to find this super site.

I have a b7100 tractor with a dead engine -cracked block from frost damage-
I know silly me!!

I have found a brand new D722e engine fitted with SAE 5 flywheel housing and flywheel currently set in genset spec. It also has an extras kit Accessory Pack Including Radiator and hoses, Fuel Filter, 12V Fuel Pump.

Could I adapt this to fit my tractor if so what might be involved?

All help much appreciated

regards

moulinjegu

[Service Dept Vic]

Ya, it looks like it would probably work. The D722 would be an excellent choice to re-power that B7100.

[moulinjegu]

Hi Vic, thanks a lot, will order the motor today.
One thing, it will not have a pump to drive the hydraulics as it is in generator spec.
Will the pump from my old one fit? and will there just be a blanking plate covering where it fits.

regards

moulinjegu

[Service Dept Vic]

It should.....make sure to keep the old engine to scavenge parts and brackets etc off

[moulinjegu]

Hi, new engine arrived today. First look shows adaptation is going to be more difficult than anticipated.

New engine D722e is smaller in many ways than the D750 it is replacing.
Motor is narrower and has different fixing for the side members, that's not a problem just a bit of blacksmith type engineering.

Two bigger problems. The new engine came with a SAE flywheel and housing; I have removed both. I can fit the flywheel from the D750 it fits fine, I just hope that the flywheel is not used to balance the engine or I could have a problem there.

The back plate from the old engine does not share any of the fixings to the block with the new one. If I could obtain a backplate for the new engine would it have the same fixings for the clutch bell housing that is on the tractor?

The other major problem is the hydraulic pump for the 3 point linkage. The new motor does not have one, there is a round plug in the place where the pump on the old motor was fitted and it is not obvious how this is removed. I have removed the cover plate on the other end and the shaft at that end has the drive notch in it. The old pump is much too large to fit to the new motor.
does anyone know what pump can be used and where it can be fitted.

I visited my local dealer this afternoon but he was less than helpful.

If anyone can help with info and part numbers I will be much obliged.

I am having difficulty finding manuals and part numbers for this motor.

All help welcomed.

moulinjegu

[Service Dept Vic]

These are not good things.

Sounds like you will need a different adapter plate to mate the existing transmission and the new engine. The D722 engine is used in Kubotas G1900 and GF1800 Front Mowers, but they run an HST transmission.

The hydraulic pump can be run off the front PTO, installing it between the rails of the front bumper and powered with a shaft off the front PTO stub.

You may have to have that existing plate modified/redrilled to match the bolt pattern on the new engine.

I'll do a little more looking in the parts manuals and see what I can come up with.

[moulinjegu]

Hi Vic,

Have found a UK Kubota dealer who is really helpful. He can supply a backplate to suit the D722e engine, he has sent me a dimensioned drawing of it and comparing it to the original back plate it looks to me as if the easiest solution would be to use both backplates welded together. This would mean that the engine flywheel assembly would be moved forward by 3.5mm relative to the clutch operating mechanism. Is there enough clutch adjustment to cope with this? If not then I will have to get a composite backplate manufactured with the engine fixings of the D722e and the clutch housing fixings of the D750, more costly and longer time scale.

Like the lateral thinking for the hydraulic pump, however by my reckoning the pump would be running backwards and at twice the speed.

The guy in the UK has found a pump designated Kit 103 that will fit to the d722 engine but it is much smaller than the original and may possibly not have enough output to drive the 3 point linkage properly. Since it is not too expensive I'm inclined to get it and give it a try.

Please let me know what you think, especially with respect to the clutch.

Regards

moulinjegu

[Service Dept Vic]

A very creative solution to what could be a sticky problem. 3.5mm for the metrically challenged, is about .14", or approx 3/16"

I think the clutch would adjust to compensate for the difference, or tolerance. The pilot bearing should be OK.

I think you'll have enough input shaft spline and clutch release throw. Starter going to be OK?

The hydraulic pump can be operated in either direction, just watch where the suction and pressure sides are, You may have to switch them.

Will you have enough front driveshaft length, and will everything bolt back up the same given this new geometry?