Gear Pump Retrofit - Rev A

My gear pump retrofit for the vane pumps has been quite popular but making them fast enough to keep up with demand has been a real problem. I decided there had to be an easier way and this is what just came out of the engineering department ;-)

It uses the NCA-905C gear housing that was used on the piston pumps. Unlike the vane pump housings I can get them new on the aftermarket AND they already have provision for a needle bearing and a tapered roller bearing to support the wobble shaft in the piston pump. It's an easy modification to machine the pump mounting ears off and rebore the oil seal seat for a double row radial ball bearing. A new easy to make intermediate shaft that runs in the OEM needle bearing and new radial bearing replaces the wobble shaft, oil seal, and tapered roller bearing and a simple adapter to marry the gear pump to the end of the housing completes the retrofit. I also think it looks a lot more "professional" than the blocky adapter I was using. This one is going to a customer who has been waiting a very long time. He will verify the fit and function for me but I don't expect any problems and expect to have these conversions available in the near future. They will be complete direct bolt on replacements for either the piston or vane pump. Simply remove the old pump, cut the hydraulic lines off, bolt on the new pump and reconnect the lines with the hoses and fittings provided. Hopefully I will be able to do a better job of keeping pace with demand.....

TOH

COOL!

Good work for a Hokie! :wink:

I really like the looks of that pump.
Cutting the lines on a NAA just seems sacrilegious though.
Those dang lines are $300+ per set already!
Maybe a future modification/addition? :idea:

(quoted from post at 21:15:34 09/22/16) I really like the looks of that pump.
Cutting the lines on a NAA just seems sacrilegious though.
Those dang lines are $300+ per set already!
Maybe a future modification/addition? :idea:

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Yes - it looks MUCH more professional than the first version. On the later tractors I incompletely replace the aluminum manifold between the pump and the transmission with hoses and a simple port adapter at the transmission. On the NAA I don't see any way to connect the flanged ends on the OEM lines to the gear pump. I could run the hoses all the way to the rear but that adds to the cost, requires some custom port adapters for the underside of the tractor, and exposes the hoses to ground hazards. I really don't see any justification for the added complications because unless you are an originality freak once you go with the gear pump you will never want to go back ;-)

TOH

I like it! Your one talented thinker and
machinist indeed!

INTERESTING... as ALWAYS!!! Thanks for Posting!!

Almost makes me wish I had a need for one.
Looks super

TOH,

You wrote:

"It uses the NCA-905C gear housing that was used on the piston pumps."

It [b:d44a679270]does[/b:d44a679270] look more like a conversion that belongs, as opposed to a more obvious adaptation. The look was actually a consideration for me but not one that would have kept me from going your gear pump route.

I'd like to see a photo of the tractor sporting your first one.
I'll check your site to see if you have updated the photo there.

Will the cost increase because you have to get the piston pump gear housings, or will the cost stay the same because you don't have to make the adapter blocks?

I know I'll be a candidate for one soon but for now I'm still nursing this rattling old vane pump along.

Thanks,
Terry

Looks very good. Nice job.

Very nice. Would a set up like that also be available for a 3 cyl 2000?

Great job TOH!
Keeping them alive one old tractor at a
time.
What is the volume of that pump.
I think the old ones were about 4 gpm.
Benj R,
TOH made that retrofit because rebuild parts
for the old vane pumps are no longer
available. Parts for the piston pump on a
2000, 3000 are readily available and not too
expensive.
Which brings up another question for TOH.
The piston pump on a 3 cyl 2/3000 puts out
about 4.2 gpm. The next generation 2600,
3600 used a gear pump (with screw on oil
filter) which puts out exactly double that
rate = 8.4 gpm.
So what would happen if you put a gear pump
on a 2/3000 and doubled the flow?
If it matters, the cam, drive gear and
casting on both engines are identical. Not
sure about the diameter of the suction and
pressure lines though. I "think" they are
about the same dia. 4.2 gpm is a bit slow to
run a loader but 8.4 is getting up into the
adequate range. Plus you'd have an easily
accessible filter.
Something I've pondered before...

(quoted from post at 16:27:14 09/23/16) Great job TOH!
Keeping them alive one old tractor at a
time.
What is the volume of that pump.
I think the old ones were about 4 gpm.
Benj R,
TOH made that retrofit because rebuild parts
for the old vane pumps are no longer
available. Parts for the piston pump on a
2000, 3000 are readily available and not too
expensive.
Which brings up another question for TOH.
The piston pump on a 3 cyl 2/3000 puts out
about 4.2 gpm. The next generation 2600,
3600 used a gear pump (with screw on oil
filter) which puts out exactly double that
rate = 8.4 gpm.
So what would happen if you put a gear pump
on a 2/3000 and doubled the flow?
If it matters, the cam, drive gear and
casting on both engines are identical. Not
sure about the diameter of the suction and
pressure lines though. I "think" they are
about the same dia. 4.2 gpm is a bit slow to
run a loader but 8.4 is getting up into the
adequate range. Plus you'd have an easily
accessible filter.
Something I've pondered before...

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That particular pump in that application is 4 GPM at ~2000 engine RPM and sized to match the output of the OEM piston/vane pumps on that generation of tractors.. You can put a bigger pump in it's place but unless you have a hydraulic system that can handle the increased flow you may not like the result. If later models used the same gear drive setup and a bigger pump replacement is just as easy.

I devised the retrofit because both the piston and vane pumps are expensive OEM specific parts that can be easily and very cost effectively replaced with a modern industry standard OTS pump. A new OEM piston pump is $700+. A new SAE-A gear pump is $100. They both do the same thing.

TOH

(quoted from post at 11:20:47 09/23/16) Very nice. Would a set up like that also be available for a 3 cyl 2000?

Click to expand...

Se my response to Ultradog. I like to tinker....

TOH

That's one heck of a savings.

(quoted from post at 21:47:17 09/27/16) That's one heck of a savings.

Click to expand...

Don't forget the cost of the conversion ;-) But what I really like is it looks good like it belongs. Can't wait to see it mounted on the tractor....

TOH