Sherwood GC1-01 Raw Water Pump for Cummins Diesel Engines
The Sherwood GC1-01 is a bronze raw water pump built to keep Cummins diesel engines running at a safe operating temperature by drawing in outside water and circulating it through the engine's cooling system. It's the current version of the pump line, having taken over for the older Sherwood GC1, and it was engineered so it can be installed in place of that earlier unit without reworking the mounting or plumbing. Owners and technicians who already have a GC1 on an engine can move to the GC1-01 and expect the same bolt pattern, the same flange mount, and the same 1-1/2" hose connections they're used to.
Inside, the pump pairs a solid bronze housing with a neoprene impeller and a mechanical shaft seal, a combination chosen for engines that pull in raw water rather than running on a closed freshwater loop. The stainless steel drive shaft rides on a ball bearing and is backed by a rear support bushing, which helps the shaft handle the side loads that come from constant duty rather than just occasional use. A full cam inside the housing keeps the impeller vanes flexing consistently against the pump wall, which is what actually moves the water through at the volume a diesel engine needs.
For anyone maintaining or repairing a Cummins-powered engine that originally shipped with a GC1, the GC1-01 is the straightforward path forward. It's built by Sherwood specifically as the direct successor, so there's no guesswork about fit, and the repair kits, gaskets, and impeller parts that keep it running are readily available whenever service is due.
Key Features:
- Bronze pump housing for corrosion resistance in raw water service
- Neoprene impeller for reliable water displacement
- Mechanical shaft seal for extended seal life
- Stainless steel drive shaft supported by a ball bearing
- Rear support bushing to help absorb operating loads
- Full cam design for consistent impeller performance
- Flange-mounted, gear-driven installation
- Direct replacement for the earlier Sherwood GC1 pump
Applications:
- Cummins diesel engines originally equipped with a Sherwood GC1 pump
- Cummins B Series (early production) 250 HP diesel engines
- Raw water cooling systems on Cummins-powered marine engines
- Engine cooling system service and pump replacement projects
Specifications:
- Part Number: GC1-01
- Replaces: Sherwood GC1
- Port Size: 1-1/2" inlet and outlet
- Pump Body Material: Bronze
- Impeller Material: Neoprene
- Shaft Seal Type: Mechanical
- Cam Type: Full cam
- Drive Shaft Material: Stainless steel
- Mounting Style: Flange mounted, gear driven
- Compatible Impeller Kit: 15000K
- Compatible Minor Repair Kit: 23980
- Compatible Major Repair Kit: 23981
- OEM Cross Reference: Cummins 3912962
Frequently Asked Questions
Q: Can the Sherwood GC1-01 be installed as a direct swap for an old GC1 pump?
A: Yes. The GC1-01 was designed to replace the GC1 using the same flange mount, drive connection, and 1-1/2" port sizing, so no modification to the mounting or hose setup is needed.
Q: What impeller does the GC1-01 use, and how often should it be replaced?
A: It uses a neoprene impeller from the 15000K impeller kit. Like any raw water impeller, it should be inspected regularly and replaced at the first sign of cracking, hardening, or worn vanes, since a failing impeller reduces cooling flow.
Q: Does the GC1-01 come with a repair kit included?
A: The pump itself is sold as a complete unit. Minor repair kit 23980 and major repair kit 23981 are available separately for future service work.
Q: Is the GC1-01 suitable for continuous duty use?
A: Yes. Its ball-bearing-supported shaft, rear support bushing, and mechanical seal are built for the sustained loads of continuous engine operation rather than only light or intermittent use.
Q: Which engines is the Sherwood GC1-01 designed for?
A: It's built for Cummins diesel engines that originally used the Sherwood GC1, including early Cummins B Series 250 HP engines that use a raw water cooling setup.
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