Need ideas for broken front PTO flex shaft. (L1730 Loader on L245)

RandR10

New member

Equipment
LB2204 (Kioti version of L2204)
Jun 17, 2021
11
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1
Raleigh, NC
Sorry to resurrect a dead thread, but my tractor has the same output shaft off the front of the motor and I can't find anything that tells me what the exact spec is for that splined shaft. I'm trying to figure out if I can make a custom pump setup because my loader runs very slow off the tractor hydraulics. I'm encouraged that you were able to use a lovejoy type coupler because that's where my head was going. It's tight in there between the frame rails so it's hard to get a good measurement, but I'm measuring about 24.5mm, so I'm assuming the actual spec is 25mm if it's metric. Anyone know the spline count? Is this a standardized spline type or is is proprietary to Kubota?
 

TheOldHokie

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L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Apr 6, 2021
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Myersville, MD
windyridgefarm.us
Sorry to resurrect a dead thread, but my tractor has the same output shaft off the front of the motor and I can't find anything that tells me what the exact spec is for that splined shaft. I'm trying to figure out if I can make a custom pump setup because my loader runs very slow off the tractor hydraulics. I'm encouraged that you were able to use a lovejoy type coupler because that's where my head was going. It's tight in there between the frame rails so it's hard to get a good measurement, but I'm measuring about 24.5mm, so I'm assuming the actual spec is 25mm if it's metric. Anyone know the spline count? Is this a standardized spline type or is is proprietary to Kubota?
Nothing wrong with 24.5mm. I did the arithmetic a while back using the info posted in another thread and believe it is a "standard" module pitch metric involute spline. Matching it will be hard/expensive. Probably much easier to make a new hub for the crankshaft pully and use something a little less exotic like a square keyway.

Dan
 
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TheOldHokie

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L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Apr 6, 2021
8,751
4,486
113
Myersville, MD
windyridgefarm.us
Sorry to resurrect a dead thread, but my tractor has the same output shaft off the front of the motor and I can't find anything that tells me what the exact spec is for that splined shaft. I'm trying to figure out if I can make a custom pump setup because my loader runs very slow off the tractor hydraulics. I'm encouraged that you were able to use a lovejoy type coupler because that's where my head was going. It's tight in there between the frame rails so it's hard to get a good measurement, but I'm measuring about 24.5mm, so I'm assuming the actual spec is 25mm if it's metric. Anyone know the spline count? Is this a standardized spline type or is is proprietary to Kubota?
As a follow-up here is an off the shelf splined hub (192161) and shaft (194354) used for front pumps on older Ford tractors. I have installed many of them. You could probably make a simple crankshaft pulley adapter for the B7100 that would let you bolt it on and go..

Dan

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RandR10

New member

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LB2204 (Kioti version of L2204)
Jun 17, 2021
11
0
1
Raleigh, NC
Nothing wrong with 24.5mm. I did the arithmetic a while back using the info posted in another thread and believe it is a "standard" module pitch metric involute spline. Matching it will be hard/expensive. Probably much easier to make a new hub for the crankshaft pully and use something a little less exotic like a square keyway.

Dan
Yeah, the more I look at this problem the more it seems like modifying the stock pump location to accept a higher flow pump might be the way to go. I'm thinking a 2 bolt pump with the AA sized flange would be the way to go because it has the same pilot size Engine on my tractor is the same engine and pump as an L245, a DH1101 with the gear drive off the back of the injection pump. Does anyone know what kind of revs this turns the pump vs. engine speed? I know the injection cam itself turns at half engine RPM. I found a pic online of the 38 tooth gear off the back of the injection pump but I can't find one to get a tooth count on the driven gear on the pump itself.
 

PoTreeBoy

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L35 Ford 3930
Mar 24, 2020
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WestTn/NoMs
Sorry to resurrect a dead thread, but my tractor has the same output shaft off the front of the motor and I can't find anything that tells me what the exact spec is for that splined shaft. I'm trying to figure out if I can make a custom pump setup because my loader runs very slow off the tractor hydraulics. I'm encouraged that you were able to use a lovejoy type coupler because that's where my head was going. It's tight in there between the frame rails so it's hard to get a good measurement, but I'm measuring about 24.5mm, so I'm assuming the actual spec is 25mm if it's metric. Anyone know the spline count? Is this a standardized spline type or is is proprietary to Kubota?
Screenshot_20220908-084055-873.png

Here's how it's done on the L35. It uses flex disk couplings. All the parts, except the splined coupling could be easily made. Unfortunately, that piece is $145. Someone has mentioned replacing it with one bolted to the crank pulley.
 
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RandR10

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LB2204 (Kioti version of L2204)
Jun 17, 2021
11
0
1
Raleigh, NC
View attachment 86770
Here's how it's done on the L35. It uses flex disk couplings. All the parts, except the splined coupling could be easily made. Unfortunately, that piece is $145. Someone has mentioned replacing it with one bolted to the crank pulley.
Yeah those splines are really seeming like a deal breaker. I actually found an OEM style coupler for these, but they're not cheap, plus all the fabrication involved, along with the extra plumbing. Not a lot of room on these size tractors as it is, so I'm reluctant to go that route now. Boring and broaching the existing driven gear along with drilling a couple holes in the housing to accept the 2-bolt pump seems like the most viable option to increase pump displacement at this point.

Found the info I was looking for on the RPM by the way. The driven gear is 30 tooth. So if the drive is 38 tooth, that's a 1.26 ratio, so the pump at engine 2800 RPM high idle the drive gear will be spinning 1400 RPM and the driven gear (pump input) is going to be spinning 1773 RPM.

That means with this little 10 cc pump we're currently at only 4.68 GPM for the whole hydraulic system to feed off of. No wonder the loader runs so slow. After some goes through the steering priority valve, we're left with very little flow. I could close to double that no problem and not have any issues with the engine running it. The problem now is finding a pump that's large enough displacement but small enough to physically adapt to that housing. I don't don't know if I can get a AA 2-bolt pump that big.
 

RandR10

New member

Equipment
LB2204 (Kioti version of L2204)
Jun 17, 2021
11
0
1
Raleigh, NC
Found the info I was looking for on the RPM by the way. The driven gear is 30 tooth. So if the drive is 38 tooth, that's a 1.26 ratio, so the pump at engine 2800 RPM high idle the drive gear will be spinning 1400 RPM and the driven gear (pump input) is going to be spinning 1773 RPM.

That means with this little 10 cc pump we're currently at only 4.68 GPM...
Never mind. I found info in the parts book for my tractor that says different. That's apparently what an L245 runs, but mine has different tooth counts for the gears. They put that after the description in the parts book. They're 22 tooth on the drive gear and 45 on the driven for my tractor, so that brings it pretty close to a 1:1 for engine speed. I'm at 7.56 GPM for my tractor. Loader seems unreasonably slow considering that number.