Spool & sleeve service
Spool wear, contamination scoring, and lap restoration on Continental Hydraulics, Vickers / Eaton, and Rexroth bodies.
Fisher Servo Valve Repair
Independent third-party component-level repair of legacy Fisher injection molding machine valves. Continental Hydraulics, Vickers / Eaton, and retrofitted Bosch Rexroth proportional bodies on 100 to 500 ton machines.
Where These Valves Sit
Four Fisher machine contexts
Fisher machines were American-built injection molding equipment. Many remain in active use. Below are the four common contexts seen at the bench.
01
100-250 ton machines
Smaller-tonnage Fisher machines for consumer products, medical components, and accuracy parts. Vickers / Eaton and Continental Hydraulics proportional valves.
02
300-500 ton machines
Larger machines for automotive parts and industrial components. Same Continental Hydraulics and Vickers valve platforms with higher flow ratings.
03
Retrofitted machines
Many Fisher machines have been modernized with updated controls. Retrofits commonly use Bosch Rexroth proportional valves replacing original Continental / Vickers bodies.
04
Auxiliary & legacy units
Continental Hydraulics proportional valves come through the bench from auxiliary positions on Fisher machines across all tonnages.
What NC Servo Does
Component-level repair on Fisher valves
Each unit is opened, inspected, and rebuilt at the component level. Failed parts come from inventory or off donor units. Bench verification before ship.
Coil & solenoid work
Coil rebuild on legacy Vickers and Continental proportional bodies. Insulation breakdown is common after decades of service.
Seal & o-ring service
Aged elastomeric seals harden and crack. Full seal-pack replacement during every rebuild.
Bench testing
Hagen-Busch and older-style hydraulic stands. Hysteresis, null shift, and step response data on request.
Donor parts service
Aftermarket and donor parts for legacy Continental Hydraulics and Vickers bodies. Many are no longer in OEM stock.
Repair scope
Bench-level component work on the valve hardware. PLC programming, machine parameter setup, and integration stay with the customer.
Brands
Fisher servo valve brands
Top brands seen on Fisher hydraulics. Click through for the dedicated brand page.
Common Faults
What usually shows up on Fisher valves
Fisher machines are decades old. Age-related valve degradation is the primary concern, compounded by contamination accumulated over years of operation.
| Coil insulation breakdown | Solenoid coils on Vickers and Continental valves degrade after decades of thermal cycling and electrical stress. Drives intermittent control loss. |
|---|---|
| Seal degradation | Elastomeric seals harden and crack with age. Drives internal leakage and unpredictable valve behavior. |
| Spool wear | Worn spool lands and degraded clearances on aged Vickers and Continental bodies. Common on high-cycle machines. |
| Contamination buildup | Years of accumulated contamination in older hydraulic systems jam spool edges and reduce valve response. |
Workflow
From part number to ship-back
Same four-step path through the shop whether the unit came off an original Fisher machine or one that's been retrofitted.
- 01
Get in touch
Call or email with the part number, machine context, and a photo of the nameplate if it helps.
- 02
Bench review
Tech opens the unit, inspects spool and coil, and runs it on the hydraulic stand to confirm what failed.
- 03
Cost & approval
We call back with the cost and a rough turnaround. Nothing is started without your sign-off.
- 04
Repair, test, ship
Failed components replaced from inventory or off donors, the valve verified under pressure, and shipped back.
FAQ
Common questions about Fisher valve repair
Application-specific questions. For brand-specific FAQs, see the dedicated brand page above.
What proportional valve brands are used in Fisher machines?
Fisher injection molding machines (American-built equipment from that era) most commonly used Continental Hydraulics proportional valves and Vickers / Eaton proportional valves. Retrofitted machines may also feature Bosch Rexroth proportional valves.
Can you repair retrofitted Fisher machines?
Yes. Many Fisher machines have been modernized over the years with updated controls and replacement valves. Whether the valve on the bench is original Continental Hydraulics, Vickers, or a Rexroth retrofit, the repair scope is the same.
Are OEM replacement parts still available for Fisher machines?
OEM Fisher replacement parts are increasingly difficult to source. The valves themselves are commercial Continental Hydraulics, Vickers / Eaton, and Rexroth bodies that NC Servo can rebuild from inventory and donor stock.
How long does a repair usually take?
Lead time varies job to job, partly because parts are often pulled from donor boards. Give us a call with the part number and the situation.
Do you provide Fisher machine programming or software configuration?
No. NC Servo handles bench-level component repair on the valve hardware only. PLC programming, machine parameter setup, and integration stay with the customer or OEM.
What if the valve is beyond economic repair?
If the valve is not fixable, we will let you know and help source a replacement.
What is the warranty?
One year on parts and workmanship for repairs and rebuilt units. Standard exclusions apply for contamination, improper installation, and out-of-spec operation.
More from NC Servo
Related repair coverage
Other injection-molding pages and the brand pages most-tied to Fisher hydraulics.
IMM hub
All injection molding builders we cover, plus shared hydraulics context.
New Britain
Other legacy American IMM coverage with similar hardware.
Sterling
Other legacy hydraulic IMM coverage.
Vickers brand page
Vickers KBDG, KFDG, KDG and broader Vickers proportional valve coverage.
Eaton brand page
Eaton industrial proportional valve coverage.
Valve repair hub
Full directory of 20+ valve brands.
What is a servo valve?
Plain-English explainer on electrohydraulic servo valves and how they relate to proportional hardware.
What is a proportional valve?
How proportional and servoproportional valves differ from true servo valves, and what gets done at the bench.
Fisher valve down? Send a part number
Give us a call or send a part number with the machine context and the symptom. We'll check the donor pool, suggest a rebuilt match if we have one, and walk through repair or cross-brand options if we don't.