Backhoe attachment.

North Idaho Wolfman said:

Thank you for the beratement! I really enjoy select members on this forum for that sort of treatment!

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Beratement? No, just stating the facts.
You can dish it out, but sure can't take it!

countryroads said:

The specs for the original gear pump ( CBN-E310 ) indicates Pressure is ( low 16 to high 20 MPa) and the Nominal Flow is 10 mL/r and Input Power at 6.58 kW, Max speed 2500 rpm.

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The CBN-E310 pump is listed on various Chinese websites, the main variance I found is the maximum speed. The few I looked at generally specified a nominal or rated speed of 2000 rpm, with a maximum speed of 3000 rpm, you note a maximum speed of 2500 rpm. What is correct, who knows, but lower speed is usually safer.
If my calcs are correct these specs equate to the following.
The rated pressure was listed in 2 variants of 16 or 20 MPa, = ~2300 or ~2900 PSI
2000 rpm x 10 ml = 20l/m or ~5.28 GPM
2500 rpm x 10 ml = 25l/m or ~6.6 GPM
3000 rpm x 10 ml = 30l/m or ~7.9 GPM
1000 rpm x 10ml = 10l/m or ~2.64 GPM
It appears Jimna tractors have a second PTO drive behind a plate on the rear which the pump can bolt straight up to. What speed that runs at, I don't know. The specs of a Jinma 254 from web note a 540 and 1000 PTO speed, however the second take off may be a different speed altogether?
https://www.youtube.com/watch?v=QWNDQmxoGg0

Personally, I'd be looking at something like this and run your tractor at ~1800 rpm, but ensure you get some validated info from wiser folks than me before purchase.
Checking cylinder size and working out speed of travel at specific flow compared to specifications (EDIT: Prior to purchase) would also be pertinent.

https://www.surpluscenter.com/Brand...P-PTO-A-3-6-S-Hydraulic-PTO-Pump-9-8902-3.axd

North Idaho Wolfman said:

Ok I'm confused
Your L285 has a standard 540 PTO (not any smaller than others that I'm aware of) with yea a slightly higher rating of 695 (just slow the motor down a little to get 540 RPM) that would run any normal backhoe PTO pump.

shootem604, There is no other Kubota OEM or aftermarket pump offered for these that I've ever heard of, that offers more flow, again.

"I have plumbed into the hydraulic system to install rear hydraulic couplers"

Did you put any kind of valve in the plumbing?
How exactly did you plumb it? tee's or a loop?

The only viable choice for a backhoe is PTO powered pump, and if your going to do a three point BH you will need the top link reinforcing bracket.

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I was told this by the parts counter at the local dealership as the reason for the hydraulic pump parts number change. I didn't order one because they were going to confirm the pump specs for me. Where would one find information on the flow rates?

Ok, I'm going to try to answer my own question from above. It seems that some tractors like my L245 came with a 3.7 GPM hydraulic pump and some tractors like the L295 came with a 5.5 GPM pump (Tractor Data). The original pump part numbers for these tractors (including 37150-36100, 35110-76101, 334150-36100, 34150-36102, 34150-36103, 34150-36110, 35180-36100, 37150-36110, 70000-36100) have all been replaced by 35110-76100 which fits the L175, L185, L245, and L295 variants. Presumably this is a 5.5 GPM part, but I have no source for that.

Time to drop in at the local dealer again and see if they have the numbers. I can tell you that my FEL is relatively slooow, even at 2000 RPM. When I am at my dad's and run his BX it is snappy at any RPM - I'd like to get some better response like that from mine.

Flow requirements for the hoe are determined by required piston travel speed, so cylinder stroke length, cylinder/rod diameter, x flow rate controls that. Per previous gleaned pump info
2000 rpm x 10 ml = 20l/m or ~5.28 GPM
2500 rpm x 10 ml = 25l/m or ~6.6 GPM
3000 rpm x 10 ml = 30l/m or ~7.9 GPM
1000 rpm x 10ml = 10l/m or ~2.64 GPM

The actual speed of the Jimna pump needs to be known to determine it's output if it can't be obtained from a dealer or on the web.
So say the cylinder diameters are smaller than a B26 and a shorter stroke because of a smaller hoe, then they would cycle/stroke (fully extend or retract) at the same speed as a B26 with a lower flow rate. As previously noted, it's worth measuring the cylinders and doing some calcs.

"If" the Jimna direct bolt on pump runs at 2000 rpm and produces 5.28 GPM to adequately run this hoe, then getting something close to that would be the best solution.
On another forum a user states - <L285 Kubota Service manual lists the hydraulic pump output as 18.5 lit./min (or 5 gpm) at 2400 rpm>
"If" this is correct, and the requirements of the hoe are around the 5.3 GPM, then tractor hydraulics "may" run this hoe reasonably well. We know these smaller hoes aren't the greatest compared to commercial units, but may be OK for limited use at these specs.
So if someone wants to chase up the spec of the L285 tractor pump and give a Jimna dealer a ring and see if they can supply accurate pump speed it would be worthwhile.

I had a quick glance of an online service manual but didn't notice the specs of the L285 pump, it was a quick glance, and not a full service manual. If someone has access to the service manual, please check it.
If the OP has the fittings to hook up to his tractor as is and run at WOT he can see how it performs. But chasing the cylinder info diameters, stroke length, Jinma data, tractor pump data would be a good start.

Can another pump be fitted as being investigated by shootem604?

In another thread Service Dept Vic states < The 1200 Series loader was fitted to the L175, 225 and L285. The lift capacity is 800 lbs, relief pressure is 1600 psi and the pump produces 3.7gpm to make it all work nice> (which is a long way from the 5GPM possibly noted in the manual) and he also notes
<The L235 fitted with its K90 factory loader whould lift 800 lbs with a relief setting of 1950 lbs and a pump that delivers 6.2 gpm OE>

So if an L235 pump is indeed 6.2 GPM AND it fits an L285, AND the Jimna specs are in that range, there may be a solution?
EDIT: It appears the L235 is a splined shaft, appears L285 tapered, so this won't fit if that's the case?

One thing to note about my previous comments, the info from service dept vic would also need to be verified, while he is in the know, he may have grabbed the info from tractordata, which may or may not be accurate.

Yep as previously mentioned, it will work, at what speed is the Q!

Something to consider when hooking up unknown origin implements (a general consideration for anybody)

The hyd fluid in the implements cylinders/motors/hoses may be a different specification to yours, especially if you run synthetic like SUDT2 etc. It may also have water contamination etc.

So if you wish you can sample the fluid, or drain fluid from hoses and both sides of cylinders etc., or just plug it in. Personally, I would remove the QC from the return hose and operate the swing valve, and push the hoe to the side expelling fluid from the return hose into a bucket and have a decent gander at it. But that's just me. If it's good clean fluid I'd consider hooking it up as I don't run synthetic (depending on what I know of the unit). But if I ran synthetic, or noted any contamination, I'd drain and exercise all cylinders manually to remove the oil and then be ready to add SUDT2 etc. to the tractor. YMMV.

YMMV = your mileage may vary. Meaning you may get different results than reported.