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About
A direct replacement pumphead for portable close-coupled pumps with IEC 71 motors. Engineered for fast, quiet, and reliable fluid transfer.
- Flow Rate vs. RPM: 12 GPM @ 1800 RPM | 20 GPM @ 2850 RPM | 25 GPM @ 3450 RPM.
- Direct Fit: Designed for IEC 71 motors with a 14mm keyed shaft.
- Smooth Operation: Large displacement helical-cut steel gears for fast and quiet operation.
- Ready to Plumb: 1" NPT ports (Includes two 1.25" hose barbs).
The ultimate cast-iron replacement pumphead. Engineered to move heavy gear oils, waste motor oil, and diesel, this is the exact head used on our flagship Goldstream portable transfer pumps.
In a true heavy-duty fluid transfer system, your electric motor is the expensive workhorse that should last for years, while the pumphead inevitably takes the abuse of moving heavy, abrasive oils. The GSM25 is a cost-effective, direct-replacement pumphead designed for portable close-coupled pumps with IEC 71 motors, getting you back to pumping at peak efficiency in minutes.
Key Features & Benefits
- Scalable Performance: The flow rate scales with your motor's speed. Pair with 3450 RPM for 25 GPM, 2850 RPM for 20 GPM, or 1800 RPM for high-torque 12 GPM transfer.
- Fast & Quiet Operation: Equipped with large displacement, helical-cut steel gears that provide a nearly pulseless flow, drastically reducing vibration and noise during heavy transfer jobs.
- Universal Fit: Designed as a direct bolt-on fit for IEC 71 standard electric motors utilizing a 14mm keyed shaft.
- Self-Priming: Creates strong suction lift right out of the box, saving you time and hassle.
Technical Specifications
| Feature | Specification |
|---|---|
| Oil Viscosity | Fuel Oil to Heavy Gear Oil (WMO, WVO, Diesel) |
| Flow Rate vs. RPM | 12 GPM @ 1800 | 20 GPM @ 2850 | 25 GPM @ 3450 |
| Pumphead Material | Heavy-Duty Cast Iron |
| Shaft Size | 14mm Keyed Shaft |
| Port Size | 1" NPT Inlet / Outlet |
| Motor Compatibility | IEC 71 Frame |
Motor Sizing & Fluid Viscosity Guide
Thicker oils require significantly more torque to move, especially at higher speeds. Pairing this pumphead with the correct motor is critical to prevent your motor from overheating. Use the guidelines below to size your custom build:
| Motor Speed (Flow) | Fluid Viscosity / Type | Minimum HP Required |
|---|---|---|
| 1800 RPM (12 GPM) | Cold Motor Oil, Waste Oil (WMO) | 3/4 HP |
| 3450 RPM (25 GPM) | Light Oils (Diesel, Warm ATF) | 3/4 HP |
| 3450 RPM (25 GPM) | Heavier Oils (Cold Motor Oil) | 1 HP to 2 HP |
⚠ Important Operating Notes
- Oil Lubricated Only: The internal gears rely on the fluid for lubrication. THIS PUMP WILL NOT WORK WITH WATER. Always ensure the pumphead has fluid before extended operation. Do not pump water, gasoline, or highly flammable solvents.
What’s Included in the Box
- GSM25 Cast-Iron Gear Pumphead (IEC 71 Mount)
- Two (2) 1" NPT to 1.25" Hose Barbs
Note: Motor, shaft coupler (L070), handle, base, and hoses are NOT included. This is a replacement pumphead component.
FAQs
Product & Usage
1. Are Goldstream pumps built for professional use?
Yes. Every Monster Series and Industrial Series pump is built for continuous duty, marine environments, and the kind of fluid-transfer work that breaks cheaper pumps.
2. Can I use a Goldstream pump for my home project?
Absolutely. Our Monster Series is portable and self-priming — no tuning or tricks needed. Plug it in and move fluid.
3. Can Goldstream pumps be used in marine or outdoor conditions?
Yes. Goldstream pumps are tested in real-world marine, biofuel, and industrial conditions — heat, humidity, and long runtimes.
Maintenance & Accessories
1. What maintenance does a Goldstream pump need?
Flush with a compatible fluid after each use and keep seals clean. That's it — our gear pumps are built to run with minimal fuss.
2. Can I buy replacement parts?
Yes. Seals, impellers, gaskets, and full rebuild kits are in stock at the Pump Parts collection.
3. Do you provide installation guides?
Every pump ships with a printed install guide. Digital copies and install videos are linked from each product page.
Warranty & Guarantee
1. Do Goldstream pumps come with a warranty?
Every Goldstream pump is backed by our 1-year limited warranty against defects in materials and workmanship, when used with approved oil-based fluids.
2. How do I register my pump for warranty coverage?
Keep your order confirmation email — it acts as proof of purchase. You can also register your serial number in your account for faster service.
3. What does the warranty cover?
Defects in materials and workmanship under normal use — no fine print, no games. Wear items (seals, gaskets) are covered by a separate 1-year warranty.
4. What if my pump fails?
Call us. We'll get you a replacement or rebuild fast — usually the same week.
Purchasing & Support
1. How fast is shipping and delivery?
Most orders ship same-day from Charleston, SC, with delivery in 2–5 business days anywhere in the continental US.
2. Do you offer bulk or corporate purchasing options?
Yes. Goldstream offers dealer and fleet pricing — call us at (843) 972-4211 or use the contact form.
3. How can I reach a real technician?
Call (843) 972-4211 Mon–Fri, 8am–3pm EST, or email support@goldstreampumps.com. No call centers.
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