Is3100z Hydraulic pump replacement

Chessie

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I'm replacing both hydr. pumps in an '08, IS3100Z (with the 26 or 27hp liquid-cooled kawasaki).

Btw, I don't see a drain plug on the hydraulic drive units/ motor at each wheel. My goal is to get rid of the old, black oil in the drive units. How?

Right now, both pumps are out, and there are two, disconnected, hydraulic lines for each pump.

I'm thinking that I aim the hydraulic lines over the drain pan and spin each wheel, forward and backwards until no more (old) oil comes out of the lines... and then put a funnel and some clean oil in one of the lines and spin the wheel (whatever direction sucks in the clean oil) until clean oil flows out of the other (drain) line.

Then I can install the new pumps and a clean filter and new oil.... presto-change-oh, Bob's your Uncle, good to go with new pumps, oil and filter.

Any better method?? (assuming I don't find drain plugs...)

Thanks, Chessie
 

ILENGINE

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I think you have found the best method, and there are no drain plugs. Would be a good opportunity to check for metal contamination of the oil. Chucky metal in the oil which would indicate a failed drive motor would be a sign of what took out the pumps.
 

Tiger Small Engine

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I'm replacing both hydr. pumps in an '08, IS3100Z (with the 26 or 27hp liquid-cooled kawasaki).

Btw, I don't see a drain plug on the hydraulic drive units/ motor at each wheel. My goal is to get rid of the old, black oil in the drive units. How?

Right now, both pumps are out, and there are two, disconnected, hydraulic lines for each pump.

I'm thinking that I aim the hydraulic lines over the drain pan and spin each wheel, forward and backwards until no more (old) oil comes out of the lines... and then put a funnel and some clean oil in one of the lines and spin the wheel (whatever direction sucks in the clean oil) until clean oil flows out of the other (drain) line.

Then I can install the new pumps and a clean filter and new oil.... presto-change-oh, Bob's your Uncle, good to go with new pumps, oil and filter.

Any better method?? (assuming I don't find drain plugs...)

Thanks, Chessie
Remove oil filter and remove charge pump covers on bottom of hydraulic pumps and let oil drain.
 

Chessie

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Thank you... "charge pump covers".... are you describing the "end" of motor, furthest inboard from the wheel, with about 6 large bolts holding the end of the motor "on"? If I remove this "case end" of the motor, will I cause an issue (like leaking) when I put it back on? Will any parts of the motor fall out without the end on it?

Thank you!
 

Chessie

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I think you have found the best method, and there are no drain plugs. Would be a good opportunity to check for metal contamination of the oil. Chucky metal in the oil which would indicate a failed drive motor would be a sign of what took out the pumps.
(Thumbs up!) Thank you for the confirmation, and I like "check for metal" idea with the old oil. I'll inspect and get out a strong magnet.

Appreciate the feedback/help!
 

Tiger Small Engine

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Thank you... "charge pump covers".... are you describing the "end" of motor, furthest inboard from the wheel, with about 6 large bolts holding the end of the motor "on"? If I remove this "case end" of the motor, will I cause an issue (like leaking) when I put it back on? Will any parts of the motor fall out without the end on it?

Thank you!
You are replacing the hydraulic wheel motors if you are talking about “next to the tire.” I am talking about the hydraulic pumps when describing the charge pumps. It is usually the pump, not the wheel drive pump that goes bad. How did you confirm this?
 

Chessie

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You are replacing the hydraulic wheel motors if you are talking about “next to the tire.” I am talking about the hydraulic pumps when describing the charge pumps. It is usually the pump, not the wheel drive pump that goes bad. How did you confirm this?
Okay, forgive my misunderstanding of "charge pump". I didn't know what to call the "motors" that drive the wheels... I knew what the "pumps" were... they are belt-driven by the engine... and since they have the "motion control" handles on them, I figured that the handle controls the amount and direction of flow of the hyd. oil, which gets sent to the "motors" at the wheels....

So.. (given those definitions of pumps and motors...) I'm changing the pumps because one of them "gave up the ghost", and started leaking and was heading for seizing, bogging down the motor with it's use... and since it's 16 years old, I decided to just replace both motors. I've been meaning to replace the black oil in this machine since I acquired the mower last year.. but I've been too busy with other tasks, and I'm guessing that the former owners didn't change the fluid, so one of the pumps died. (And heck, 16 years is a good lifetime for a hydraulic pump, I hope the new ones last that long.)

As part of the task of replacing the pumps and filter, I was going to have to add new oil, and I figured that I would try to get as much of the old oil out of the motors as possible... thus my original question... I can't see any drain plugs on these motors, and the hydraulic lines (plumbing) goes "up" to the pumps, so I didn't see a gravity option to get rid of whatever oil is in the motors... I'm studying telekenisis and was contemplating inverting the whole machine, but the gas leaking out of the tanks, and the oil in the engine, and the coolant mess... I just decided to skip the whole "mentally flip the machine upside down and hold it there for 1/2 an hour and let the motors drain" idea....

It's a good machine, so I'm planning to keep it, and figured if I removed as much (or all) of the old oil from the motors, it would help the quality of the Hydraulic Oil in the system....

With the confirmation of this forum, I plan to spin the wheels manually, with the hoses over the oil pan and get out as much as possible, then flow in some new oil (spinning the wheels) until it runs clean.. then put it all back together (unless I find significant chunks of metal in the oil). Right now, the motors seem good and don't leak, so when I spin them, if they feel "tight" without any side-to-side play, then I'll hope for the best and use the old motors with the new pumps.

(What is the appropriate sacrifice for the God of Hyrdostatic Drive? The Patron Saint of Hydraulics...)

Thanks all
 

Hammermechanicman

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The is3100z came in 2 varieties. The older ones, like mine, have separate self contained hydros. The newer ones have a single pump and separate wheel motors. Sounds like the OP has an older one with separate hydros.
 

Tiger Small Engine

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Okay, forgive my misunderstanding of "charge pump". I didn't know what to call the "motors" that drive the wheels... I knew what the "pumps" were... they are belt-driven by the engine... and since they have the "motion control" handles on them, I figured that the handle controls the amount and direction of flow of the hyd. oil, which gets sent to the "motors" at the wheels....

So.. (given those definitions of pumps and motors...) I'm changing the pumps because one of them "gave up the ghost", and started leaking and was heading for seizing, bogging down the motor with it's use... and since it's 16 years old, I decided to just replace both motors. I've been meaning to replace the black oil in this machine since I acquired the mower last year.. but I've been too busy with other tasks, and I'm guessing that the former owners didn't change the fluid, so one of the pumps died. (And heck, 16 years is a good lifetime for a hydraulic pump, I hope the new ones last that long.)

As part of the task of replacing the pumps and filter, I was going to have to add new oil, and I figured that I would try to get as much of the old oil out of the motors as possible... thus my original question... I can't see any drain plugs on these motors, and the hydraulic lines (plumbing) goes "up" to the pumps, so I didn't see a gravity option to get rid of whatever oil is in the motors... I'm studying telekenisis and was contemplating inverting the whole machine, but the gas leaking out of the tanks, and the oil in the engine, and the coolant mess... I just decided to skip the whole "mentally flip the machine upside down and hold it there for 1/2 an hour and let the motors drain" idea....

It's a good machine, so I'm planning to keep it, and figured if I removed as much (or all) of the old oil from the motors, it would help the quality of the Hydraulic Oil in the system....

With the confirmation of this forum, I plan to spin the wheels manually, with the hoses over the oil pan and get out as much as possible, then flow in some new oil (spinning the wheels) until it runs clean.. then put it all back together (unless I find significant chunks of metal in the oil). Right now, the motors seem good and don't leak, so when I spin them, if they feel "tight" without any side-to-side play, then I'll hope for the best and use the old motors with the new pumps.

(What is the appropriate sacrifice for the God of Hyrdostatic Drive? The Patron Saint of Hydraulics...)

Thanks all
Don’t get so focused on that little bit of oil in the pump motors. Drain everything you can, keep it clean, install a new filter, use the correct oil, bleed the system correctly, and run it.
 

RevB

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Don’t get so focused on that little bit of oil in the pump motors. Drain everything you can, keep it clean, install a new filter, use the correct oil, bleed the system correctly, and run it.
Precisely. When you "change" auto trans fluid you can't get it all in the first go because there is so much left in the converter. Yeah, a different type of hydraulic but the principle remains. If it really bothers you that much change the fluid again in a month or so. 🤔
 
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