Hydraulic Motor Repair & Rebuild

Most hydraulic motors can be rebuilt, and when the housing and shaft are still serviceable a rebuild is often the better buy than a new motor, especially if the motor is obsolete, an OEM special, or the machine is down waiting on it. Tell RestoPower what you have and we arrange getting the motor to the shop doing the work, ours or a network shop closer to you. The teardown evaluation is free: you get a firm, itemized quote for the actual damage before a single billable hour is spent, and if the motor is not worth rebuilding we tell you so and quote a replacement instead.

We rebuild Char-Lynn orbital motors, Parker Torqmotor orbital motors, Poclain and Parker Calzoni radial-piston motors, piston and vane motors, and closed-loop hydrostatic drive motors, including Sundstrand and Eaton units. Every motor we rebuild in our shop is built to factory specification, function-tested before it ships back, and covered by our 1-year repair warranty.

The short version: free teardown and evaluation, a firm itemized quote you approve before any billable work, rebuilt to factory specification, function-tested, and, for work done in our shop, a 1-year warranty on the rebuilt motor and the labor in it. We arrange getting it from anywhere in the US to the shop doing the work.

Our shop or our repair network. Your motor is repaired either in our shop in Lake Orion, Michigan, or through the RestoPower repair network, when a network shop closer to you can turn it around faster. We tell you before any work starts, and the price, turnaround and warranty for a network job are confirmed on your quote.

Which hydraulic motors do you rebuild?

These are the motor types our repair shop works on day to day. If yours is not on the list, send the model code anyway. We cover Vickers, Eaton, Parker, Denison, Char-Lynn, Oilgear, Sundstrand, Bosch Rexroth, Racine and Poclain across pumps, motors and valves, and we will tell you straight if a unit is outside what we do.

Motor type What usually wears Parts and service data
Char-Lynn / Eaton orbital motors Shaft seal, the gerotor or Geroler set, the drive link, the valve, and bearings on bearing-supported models Char-Lynn orbital motors, Char-Lynn motor seal kits
Poclain radial-piston wheel motors Pistons and rollers, the cam, the cylinder block and distributor faces, bearings, seals Poclain parts, Poclain motor parts
Parker Torqmotor orbital motors Shaft seal, the gerotor set, the drive and valving, and bearings on bearing-supported models Parker Torqmotor, Torqmotor rebuild guide
Parker Calzoni radial-piston motors Pistons and their seals, the shaft and bearings, the distributor, and shaft seals Parker Calzoni radial-piston motors
Piston motors The rotating group (pistons, slippers, cylinder block), the valve plate, shaft bearings, shaft seal Vickers motors, Vickers motor seal kits
Vane motors The cartridge: ring, rotor, vanes and side plates, plus seals and bearings Vickers vane motor catalog
Hydrostatic drive motors (closed loop) The rotating group and valve plate, often damaged by debris from a failed pump in the same loop Sundstrand pumps and motors, Eaton heavy-duty hydrostatics

We repair Parker Torqmotor and Parker Calzoni motors and source the parts for both, so send the model code even if you only need parts. Because we keep deep hard-to-find and obsolete parts inventory, a motor other shops turn away can often still be rebuilt here.

Repair, rebuild, reman or exchange: what does my motor need?

Everyone uses these words differently. For a hydraulic motor they come down to four jobs.

Job What it means on a motor When it makes sense
Repair We fix the specific fault, such as a blown shaft seal, and leave the rest of the motor alone. The motor still makes torque and speed, and the leak or fault has an obvious single cause.
Rebuild (overhaul) Full teardown. Every seal and wear part replaced, worn surfaces machined or replaced, reassembled to the original specification and function-tested. The motor has lost torque, slips under load, runs hot, or has been leaking long enough that you do not trust the rest of it.
Remanufacture (reman) Stripped to the bare housing, every wear component replaced or restored to as-new tolerance, and brought up to the latest supported revision where one exists. You want the longest life out of the housing you already have. Costs more, lasts longer.
Exchange Where we have a rebuilt motor on the shelf, you get it now and send your core back after. The machine is down and every day costs money. Least downtime of the four.

Not sure which one you need? That is what the free evaluation is for. We will recommend the cheapest option that actually solves the problem, and you can ask for more than one price on the same quote.

Is it worth rebuilding a hydraulic motor, or should I buy new?

The lazy answer is to compare the rebuild quote with the price of a new motor and take the lower number. That works on a common, current motor. It is the wrong arithmetic on an old one, an OEM special, or a motor holding up a machine in season. These are the factors that actually decide it.

Factor Leans rebuild Leans replace
Housing and shaft condition Housing sound, shaft and splines serviceable. You are buying wear parts, not a motor. Cracked housing, a bore scored past cleanup, or a shaft that spun in its bearing and chewed the bore.
Is the motor still available new? Obsolete or dropped from the catalog, so a "replacement" means new porting, a new shaft or a new mount. Current production, common, and on a shelf somewhere.
Lead time on a new motor The new one is back-ordered or built to order and the machine cannot wait. A new motor is available quickly and the rebuild would take longer.
OEM special The motor was built for one machine maker, with its own shaft, porting, valving or seal set. Rebuilding your own unit keeps every one of those details. A standard catalog motor that any distributor can match off the nameplate.
Size of the motor Large motors, where the wear parts are a fraction of the price of the assembly. Small, cheap, high-volume motors where the labor alone approaches the price of a new one.
Cost of downtime An exchange unit is on the shelf, or the rebuild beats the new motor's lead time. A new motor is the fastest way back to work.

Be careful with OEM specials. Motors built for a particular machine maker often carry a different shaft, port or seal arrangement from the catalog motor with a similar number. A "drop-in" new motor bought off a similar part number is how the wrong unit ends up on the machine. Rebuilding the motor you already have sidesteps that completely.

How much does it cost to rebuild a hydraulic motor?

There is no flat rate, and anyone who quotes one over the phone is guessing. The same part number can come in with nothing worse than a tired shaft seal, or with a scored valve plate and worn splines, and those are different jobs at very different prices. Motor jobs fall into the same three brackets as pumps:

  1. Seals only. The motor still makes its torque and speed and is just weeping. A seal kit and a few hours. Across our catalog, seal kits for most orbital motors sit somewhere between fifty and two hundred dollars, with larger and specialty kits above that. If you have the bench and the know-how, you can do this one yourself.
  2. Wear parts. Lost torque, slipping under load, heat. On an orbital motor that usually means the gerotor or Geroler set and the drive. On a piston motor it is the rotating group and valve plate. This is where frame size starts to move the number.
  3. Shaft, housing, or a motor that came apart. Now you are pricing major components against a complete replacement, and that is where an honest shop tells you when to walk away.

That uncertainty is exactly why the evaluation is free. You get a real number for your motor instead of a guess, and if a replacement is cheaper than the rebuild, we will say so. More detail on the brackets and the costs that never make the quote is on what hydraulic pump repair actually costs.

What are the signs a hydraulic motor needs a rebuild?

  • It slows down or stalls under load but runs fine unloaded. Internal leakage has gone up and the motor is passing oil instead of turning it into torque.
  • It runs hot. Oil slipping across worn internal clearances turns straight into heat.
  • Case drain flow is up on a motor with a case drain. More oil going out the drain means more slipping inside.
  • The shaft seal keeps blowing. On an orbital motor that is very often back pressure or case pressure, not a bad seal. Fix the plumbing or the new seal goes the same way.
  • Noise, knocking or rough rotation that was not there before. That can mean bearings, a damaged gerotor set or a broken piston, and it is time to stop running it before the damage spreads.
  • Drift or creep on a wheel or winch motor, where the motor should hold and does not.

Before you pull the motor, rule out the system. A weak pump, a relief valve set low, or a restricted return will make a healthy motor look tired. The troubleshooting guides walk through it: Char-Lynn orbital motor troubleshooting and hydrostatic transmission troubleshooting.

My pump failed in a closed loop. Do I need to check the motor too?

Yes. In a closed-loop hydrostatic drive the pump and motor run on the same loop oil. When the pump comes apart, the debris goes straight to the motor, and the motor swallows it. A motor that took that debris will fail next, and when it does it puts metal back into the loop and destroys the new pump with it. We see this all the time.

So if the pump came apart internally, do it properly:

  1. Send the motor for evaluation along with the pump, or at minimum get it opened and inspected.
  2. Flush the loop and the lines, and fit new filters.
  3. Check anything else downstream that saw the same oil.

Never drop a rebuilt pump into a loop that still has the old motor and the old oil in it. A rebuilt unit put into contaminated oil can be destroyed in minutes, and that failure will not be covered by any warranty.

How does the motor rebuild process work?

  1. Tell us what you have. Email the nameplate model or part number, or request a quote, and we arrange getting the motor to the shop doing the work, with shipping instructions for you.
  2. Free teardown and evaluation. We take the motor apart, measure the wear parts and identify what caused the failure, at no charge.
  3. Firm itemized quote. You approve the price before any billable work starts. If the motor is not worth rebuilding, we say so and quote you a replacement instead.
  4. Rebuild and test. Rebuilt to factory specification with the right components and function-tested before it ships.
  5. Warranty and return. Shipped back ready to run, backed by our 1-year repair warranty.

Got a worn-out motor you are replacing rather than rebuilding? Our core buyback program takes worn, damaged and even seized motors for credit toward your next order.

What should I send with the motor?

  • The full model code or part number from the tag, every digit. A clear photo of the tag beats a typed guess. For Char-Lynn, the Char-Lynn part number decoder shows what each block means. For Poclain, see how to identify a Poclain MS motor.
  • What it is doing: weeping, slow under load, hot, noisy, drifting, or locked up.
  • The machine it came off, and whether it is an OEM special.
  • Whether the pump failed too, or the system has had any contamination.
  • Whether the machine is down right now. A motor on a shelf and a motor holding up a harvest get different recommendations, and it may make an exchange the right call.

Frequently asked questions

Can a hydraulic motor be rebuilt?

Most can. If the housing and shaft are serviceable, the seals and wear parts can be replaced and the motor returned to factory specification. A cracked housing, a bore scored past cleanup, or a shaft that spun in its bearing are the usual reasons a motor is not worth it, and we will tell you if yours is one of them.

Is it cheaper to rebuild a hydraulic motor or buy a new one?

It depends on the motor. Rebuilding usually wins on obsolete motors, OEM specials, large motors and anything with a sound housing and shaft. A new motor usually wins on small, common, current production motors where the labor approaches the replacement price. Our evaluation is free, and if new is cheaper we say so.

How much does it cost to rebuild a hydraulic motor?

There is no flat rate, because motors fail differently. A seals-only job is the cheapest, a wear-parts rebuild costs more and scales with motor size, and a job needing a shaft or housing is where rebuilding starts to compete with a new motor. Send the motor for a free teardown evaluation and you get a firm, itemized quote before any billable work.

Which hydraulic motors does RestoPower rebuild?

Char-Lynn and Parker Torqmotor orbital motors, Poclain radial-piston wheel motors, Parker Calzoni radial-piston motors, piston and vane motors, and closed-loop hydrostatic drive motors including Sundstrand and Eaton units. We cover Vickers, Eaton, Parker, Denison, Char-Lynn, Oilgear, Sundstrand, Bosch Rexroth, Racine and Poclain across pumps, motors and valves.

What warranty comes with a rebuilt hydraulic motor?

Repair and rebuild work done in our shop carries a 1-year warranty covering the rebuilt motor and the labor that went into it. For a job handled through our repair network, the warranty is confirmed on your quote. That applies even when we rebuild it with components from our own catalog.

Do I need to replace the motor if my hydrostatic pump failed?

Not always, but it must be checked. The pump and motor share the same loop oil, so debris from a failed pump goes straight through the motor. Have the motor evaluated, flush the loop and fit new filters before the rebuilt pump goes in, or the damaged motor can destroy the new pump.

Do you offer exchange hydraulic motors?

Yes, where we have a rebuilt unit on the shelf. You get the rebuilt motor now and send your core back after, which is the least downtime of any option. Ask when you request your quote.

Is there a hydraulic motor rebuild shop near me?

RestoPower rebuilds motors for customers nationwide, in our shop in Lake Orion, Michigan, and through the RestoPower repair network. Request a quote with your nameplate model and we arrange getting the motor to our shop or a network shop closer to you, so distance is not a reason to settle for a shop that cannot get the parts.

Do you send repairs to other shops?

Sometimes. We repair your motor in our shop in Lake Orion, Michigan, or route it through the RestoPower repair network when a network shop closer to you can turn it around faster. We tell you before any work starts, and the price, turnaround and warranty for a network job are confirmed on your quote.

Tell us about the motor. The evaluation is free.

Tell us the model code from the tag, what the motor is doing and whether the machine is down. We tear it down, find the cause and send a firm, itemized quote before any billable work. Work done in our shop is rebuilt to factory specification, function-tested, and backed by a 1-year repair warranty.

Request a repair quote · (810) 882-1171 · Repair and rebuild service · Core buyback

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