I have a Kubota L285. I have plumbed into the hydraulic system to install rear hydraulic couplers. My question is , would this tractor have enough hydraulic power to supply the operation of a small backhoe attachment? All comments and advice are welcome.
Backhoe attachment.
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shootem604
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L245DT with Kubota (Arps Model 22) FEL and Kubota B/L4520B (Woods 650) BH
I've been told before that these early L series Kubotas had fairly low flow hydraulic pumps because they weren't intended to run anything but the 3 point hitch. Apparently Kubota realized the North American market needed higher flow pumps and replacements are available, but if you have the factory pump as I do, your equipment may be slow, like my FEL ( I think my pump does something like 4gal/min - it seems most equipment uses twice that). I have a L245DT with a B/L4520b backhoe but it has it's own PTO driven pump and reservoir.
You can use a PTO driven pump and a second reservoir, or ask Kubota about the higher flow pump, or maybe your tractor has a splined shaft on the front of the engine that could run a pump and use the tractor's fluid (Some FELs have this setup I believe).
You can use a PTO driven pump and a second reservoir, or ask Kubota about the higher flow pump, or maybe your tractor has a splined shaft on the front of the engine that could run a pump and use the tractor's fluid (Some FELs have this setup I believe).
This is really good info. I did think about the PTO pump but my PTO shaft is smaller( I know that I can get an adapter) and the RPMs on the tractor's PTO is faster than the max on the PTO pump ( I could probably run the tractor engine at a slower speed ). All that said, I did not know that I can get a pump with higher flow for this tractor. I would like to look into this. I suppose a Kubota dealer could help me on this. If anyone else care to add something, please do. Thank you shootem604 and have a great day.
North Idaho Wolfman
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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
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 measured the PTO shaft size on my L285 to 1 and 1/8 in. . The newer tractors are 1 and 3/8 in. On eBay people are selling adapters for PTO that goes from 1 & 1/8 to 1 & 3/8
- I installed a 2 lever spool valve as a rear hydraulic remote and the way I tapped into the system is By following a post I found on this forum dated 01-08-2015 titled L175 Remote Hydraulic posted by mikeyv79 and the procedure of tapping into this type of tractor is explained here by North Idaho Wolfman. What you do here is replace a plate that is bolted on a block near the rear of the tractor where the hydraulic goes into the three point hitch. There is a block there with a face mounted plate bolted on it. This plate can be replaced by a custom ported plate to feed the remote.
- The backhoe I purchased is one with the underframe and I will try to leave this on and somehow fit it on my tractor.
- I installed a 2 lever spool valve as a rear hydraulic remote and the way I tapped into the system is By following a post I found on this forum dated 01-08-2015 titled L175 Remote Hydraulic posted by mikeyv79 and the procedure of tapping into this type of tractor is explained here by North Idaho Wolfman. What you do here is replace a plate that is bolted on a block near the rear of the tractor where the hydraulic goes into the three point hitch. There is a block there with a face mounted plate bolted on it. This plate can be replaced by a custom ported plate to feed the remote.
- The backhoe I purchased is one with the underframe and I will try to leave this on and somehow fit it on my tractor.
Sorry wolfman. I didn't realize I was answering to you. You are the one that helped me in plumbing the back remote onto my tractor. Thank you for that. I was able to do a good job there. You might be right about the PTO shaft size. I attached a female shaft to it and it fit even though when I measure I get 1 and 1/4 in. I don't see any specs anywhere about this. How do you measure this? When I measure the part where the female locks into the male, I get 31mm and when I measure from outside to outside of spline I get 1 1/4 in. Those PTO pumps are expensive in my area and I just wanted to make sure I am going the right way about it. The backhoe is a used one. The owner kept the hydraulic reservoir so I will have to get one of those also and he also said that he couldn't get enough pressure build up to run it
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North Idaho Wolfman
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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
If you measure it and get a 1 1/8 high point on the splines then get the adapter as the larger might fit on but will be loose and wobble.
One thing about these older models is there are variances in them that sometimes are not readily explainable.
Here is a cheap and easy adapter.
https://www.ebay.com/itm/T318-PTO-A...729890?hash=item36384bdd22:g:rtQAAOSwnXpbmuD3
One thing about these older models is there are variances in them that sometimes are not readily explainable.
Here is a cheap and easy adapter.
https://www.ebay.com/itm/T318-PTO-A...729890?hash=item36384bdd22:g:rtQAAOSwnXpbmuD3
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North Idaho Wolfman
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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
For testing you could temporarily hook up the BH to the loader hydraulics, it will have all the power or should, it will just be slow to move.
Use a bungee cord to hold the valve in the active position, and be aware you might need to change the flow direction on the valve it doesn't work right.
Normally the lack of pressure or power is a relief valve issue not a pump issue.
Use a bungee cord to hold the valve in the active position, and be aware you might need to change the flow direction on the valve it doesn't work right.
Normally the lack of pressure or power is a relief valve issue not a pump issue.
Thank you North Idaho Wolfman. I have a choice through Princess Auto 7.2 GPM 540 RPM PTO Pump for $500 Canadian or 20.7 GPM 540 RPM PTO Pump for $600 Canadian. I am leaning towards the more expensive one.
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North Idaho Wolfman
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Thank you. I just ordered the PTO pump, a 5 gallon oil reservoir and an oil strainer for the suction port.
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Yes you would be much happier with the 20.7 GPM than the 7.2!
Which one?
My thoughts, take them as you wish!
IIRC my dedicated B21 TLB, and B26's produce about ~7GPM, I also believe other small backhoes use around the same flow. What you are getting, I don't know?
If you buy a hoe that runs at approx 7GPM and you buy a 21GPM pump, you now have ~3 times the flow which basically means your cylinders will operate at 3 times the speed making it extremely hard to operate and control. All your hoses and valves are probably sized for lower flow, you may well build up additional pressure in the system when just sitting there doing nothing due to flow restrictions, because you are pumping 3 times the fluid than the system was designed for. This means additional heat and additional fuel.
If you get a pump with ~3 times the flow and slow the engine down to reduce the flow, instead of your engine running at ~1860 for 540 rpm for 21GPM, you now have it at idle at ~620 for 180 rpm for ~7GPM. You engine does not put out a lot of power at 620 rpm, if it does idle there at all, and the governor may be very erratic as load comes on and off.
If you want to run a backhoe ideally get a pump that is matched to the flow rating of the hoe. So if you get something needing 9~13 GPM, work out your power and engine speed requirements and required pump size to suit. Using a ~21 GPM pump you may still be limited at 1170 rpm >340 PTO> 13GPM or 810 rpm>235 PTO > 9 GPM due to reduced engine power output at lower rpm. YMMV.
EDIT: Specs used from Tractordata info
Engine rpm = 2400
PTO rpm = 695
And happy to be corrected if my calcs are wrong!
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Here are some specs of a Prince pump
SPECIFICATIONS
https://www.surpluscenter.com/Brand...rince-HC-PTO-2A-PTO-Pump-540-RPM-9-1047-2.axd
https://www.surpluscenter.com/Hydra...P-PTO-A-5-6-S-Hydraulic-PTO-Pump-9-8902-5.axd
SPECIFICATIONS
- 5.7 cu. in. displ.
- 2,250 PSI max
- 540 RPM input
- Max output 11.4 GPM @ 2,000 PSI & 18.1 Hp input
- Fits onto a 1-3/8" dia. 6T splined shaft
- In port SAE 16
- Out port SAE 12
- Size 8-3/4" x 6-1/2" x 6"
- Shpg. 37 lb.
https://www.surpluscenter.com/Brand...rince-HC-PTO-2A-PTO-Pump-540-RPM-9-1047-2.axd
https://www.surpluscenter.com/Hydra...P-PTO-A-5-6-S-Hydraulic-PTO-Pump-9-8902-5.axd
North Idaho Wolfman
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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
If your going to do a comparison, do one on a L which his is...
L35 17.3 GPM
L48 25.9 GPM
North Idaho Wolfman
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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
You are right on the HP requirements of a 20.7, they are going to be a little taxing for a L285.
A 7.2 GPM pump is too small.
I also question the price of the pump?
Here are three that all range in the $300, yes it's US prices but I don't think it would be a $300 jump for CA.
A 7.2 GPM pump is too small.
I also question the price of the pump?
Here are three that all range in the $300, yes it's US prices but I don't think it would be a $300 jump for CA.
Attachments
He clearly stated SMALL backhoe, and I also noted flow rates required for a Bradco hoe of 9~13 GPM which is noted on various websites to suit an L285.If your going to do a comparison, do one on a L which his is...
I clearly noted I had no idea on what he was fitting as he hadn't supplied that information.
Comparing a 35 year old L285 to an L35 is pushing things, comparing a 35 year old L285 to an L48 is ridiculous.
L285 power 30hp
L35 power 35hp
L48 power 48hp
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North Idaho Wolfman
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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
When someone is advised to buy a 20.7 GPM pump, when it may be far outside an ideal specification for his requirements, especially when he may have to pay freight/customs duties/taxes/exchange rates and then have to pay to send it back and do it all again, I don’t think that’s nothing, and if that's the case, I doubt the OP will be any happier about it!
Trying to justify the pump specification by comparing flow requirements of larger late model purpose built TLB’s against a small backhoe that hasn’t even been noted is just crazy!
Saying one pump or another is or isn’t suitable or one is too small, or saying he needs a big pump until specifications are known is crazy!
I’m not bent, I’m just trying to ensure the OP gets suitable information to work with. Maybe the OP will get a little bent if his ordered parts aren’t suitable, and I wouldn’t blame him.
It would be fantastic if the 20.7 GPM pump (if that is what he has ordered) suits his backhoe to a tee, but making a wild guess without suitable specifications is fraught with risk, risk that the OP shouldn’t have to take.