When you need an ANSI end-suction process pump for chemical or industrial fluid handling, the Durco Flowserve MK3 and the Goulds 3196 STi are both serious contenders. But they arrive in very different packages: one is new open-box surplus, the other is a used workhorse. The decision comes down to how much upfront risk you want to take versus how much performance headroom you need. Both pumps share the same 1.5-by-1-inch connection size, so the choice isn't about fit-it's about condition, pressure rating, and what you're willing to spend.
Quick Verdict
If you want a pump that hasn't seen service and you need the higher 275 PSI rating, the Flowserve MK3 at $3,750 is the safer technical bet. If you can work with a 250 PSI rating and want to save $2,125, the Goulds 3196 at $1,625 leaves you budget for installation and accessories. The price difference alone is enough to cover a motor or spare parts.
Price and Spec Comparison
| Feature | Flowserve MK3 | Goulds 3196 STi |
|---|---|---|
| Price | $3,750.00 | $1,625.00 |
| Price indicator | ||
| Condition | New - Open box | Used |
| Model | MK3 STD | 3196 STi 1x1.5-8 |
| Inlet x Outlet | 1.5\" x 1\" | 1.5\" x 1\" |
| Pressure rating | 275 PSI @ 100°F | 250 PSI (nameplate) |
| Material | D4 | Ductile iron |
Where Each Product Wins
- Flowserve MK3 wins if you want a surplus pump that has never been installed, a higher pressure rating, and the inclusion of an IPS Beacon 2. It's from Bitter End Trading, and they offer money back if the unit is dead on arrival.
- Goulds 3196 STi wins if you want a US-made ductile iron pump with flood-oil bearings and a 6.75\" impeller, and you'd rather keep $2,125 in your pocket. Peak Machinery lists the unit as used with a stated 250 PSI rating.
Product Notes
Durco Flowserve MK3
The Flowserve MK3 is the choice when a process pump must be as close to new as possible without paying full list price. The open-box condition means you get a unit built in 2015 with a D4 material spec and a 275 PSI rating at 100°F. It also includes an IPS Beacon 2, which could be useful for monitoring. The limitation is that Bitter End Trading clearly states there's no way to test the unit before purchase-you rely on their money-back-if-DOA promise. In exchange for the higher cost, you're buying a virgin pump that's never been installed. If your process demands the extra 25 PSI and you want a clean history, this is the one.
Goulds 3196 STi
The Goulds 3196 STi is the lower-priced of the two, coming from Peak Machinery. You get a used ANSI pump with a ductile iron casing, flood-oil bearing housing, and a 6.75-inch impeller. The 250 PSI rating per the nameplate is only 25 PSI short of the Flowserve, which is a minor gap for many services. Since it's used, the pump's condition is exactly what the photos show-there's no guarantee beyond that. The real win here is the price advantage-you get a capable pump while leaving room in the budget for the rest of the system. If you're handling water-like fluids or non-critical chemicals, the pressure difference is unlikely to matter.
Final Choice by Use Case
If your fluid handling application demands the highest listed pressure rating and you prefer a pump that's never been in service, go with the Flowserve MK3. If you need dependable ANSI process pumping and the cost difference matters more than the condition premium, the Goulds 3196 STi gives you real capability at a much lower entry point. In short, the Flowserve MK3 offers the peace of mind of a fresh, higher-rated pump; the Goulds 3196 STi offers the lower-cost path into the same ANSI pump class.
