A.Y. McDonald · Submersible Pump End
400S 8 in Stainless Steel Pump End
400 GPM stainless steel pump end for Baker NEMA 6 in and 8 in motors, 5 to 100 HP, 13 models.
400 GPM Rated Flow
5-100 HP
Fits NEMA 6 in and 8 in Motors
1276 ft Max Head (Shut-off)
5 in NPT Discharge
Built-In Check Valve
304 Stainless Steel, 431 SS Shaft
24.3-85.4 in L
55.3-153.8 lb Weight
What Ships and What It Needs to Run
Included: the pump end with its built-in check valve, cable guard, bolts and washers.
Motor required, ordered separately: a Baker motor of the same horsepower and the motor size on the pump end’s bracket (Baker 6 in motor, Baker 8 in motor). The motor table under Models & Performance gives the bracket size and a matching motor part number for each horsepower.
And the motor’s control: three-phase motors need a starter kit or drive; single-phase three-wire motors need a control box.
Overview
Baker stainless steel pump ends deliver peak capacity at 400 GPM. The 400S is a 8 in stainless steel pump end from 5 to 100 HP, with a built-in check valve and NEMA mounting bracket. Each pump end includes the cable guard, bolts and washers.
Order by model number: the number reads flow class, stainless steel, horsepower, pump size and motor bracket (for example, 90S3HP64 is the 90 GPM stainless pump end, 3 HP, 6 in pump on a 4 in motor bracket).
- Stainless steel valve guide, valve casing and built-in check valve, with NBR and stainless steel valve seat.
- NBR intermediate bearing and NBR and stainless steel neck rings.
- Stainless steel impellers locked with split cones.
- Stainless steel diffusers, suction strainer, coupling and shaft.
- Stainless steel strap and screw; NEMA mounting bracket.
Genuine A.Y. McDonald equipment, factory-new in original packaging — sold and supported by Watermain Supply, an independent industrial supplier. Watermain Supply is an Authorized Stocking A.Y. McDonald and Baker Water Systems Distributor.
A.Y. McDonald Limited Warranty
Covered for 2 years from the date of manufacture or 1 year from the date of installation, whichever comes first, under A.Y. McDonald’s standard limited warranty for Baker products.
Room to Grow
One pump end per motor. Need more head later? Step up in horsepower within the 400S with the matching larger motor; every 400S model uses the same 5 in NPT discharge, so the column pipe connection stays the same.
Shared Specifications
| Included |
Pump end with built-in check valve, cable guard, bolts and washers |
| Discharge |
5 in NPT (female) |
| Motor fit |
NEMA 6 in and 8 in Baker submersible motors, by bracket (see the motor table under Models & Performance) |
| Materials |
304 stainless steel; 431 stainless steel pump shaft; NBR bearings and seals |
| Check valve |
Built in |
| App connection |
None |
Source: Pumps by Baker catalog (Sept 2025, rev 3/26), pp. 173-174.
Models & Performance — Will It Do What You Need?
The catalog publishes the 400S performance as a curve: head against flow for each horsepower, with the most efficient operating range shaded. It prints no head-at-flow table, so this page gives the printed shut-off figures and the curve itself is in the image gallery. Read your duty point off the curve for your horsepower.
Total head in feet at 0 GPM (Shut-off), as printed
| HP |
0 GPM (Shut-off) |
| 5 HP |
80 ft |
| 7 1/2 HP |
92 ft |
| 10 HP |
135 ft |
| 15 HP |
187 ft |
| 20 HP |
265 ft |
| 25 HP |
354 ft |
| 30 HP |
420 ft |
| 40 HP |
543 ft |
| 50 HP |
669 ft |
| 60 HP |
780 ft |
| 75 HP |
975 ft |
| 100 HP |
1276 ft |
Shut-off is zero flow, a ceiling rather than a working point. Source: Pumps by Baker catalog (Sept 2025, rev 3/26), p. 174. PSI = feet ÷ 2.31.
Motor by horsepower (ordered separately)
| HP |
Motor bracket |
Matching motor |
| 5 HP |
6 in |
6 in, 460V 3Ph 3132-552 |
| 7 1/2 HP |
6 in |
6 in, 460V 3Ph 3132-554 |
| 10 HP |
6 in |
6 in, 460V 3Ph 3132-556 |
| 15 HP |
6 in |
6 in, 460V 3Ph 3132-558 |
| 20 HP |
6 in |
6 in, 460V 3Ph 3132-560 |
| 25 HP |
6 in |
6 in, 460V 3Ph 3132-562 |
| 30 HP |
6 in |
6 in, 460V 3Ph 3132-749 |
| 40 HP |
6 in |
6 in, 460V 3Ph 3132-751 |
| 50 HP |
6 in |
6 in, 460V 3Ph 3132-753 |
| 60 HP |
6 in |
6 in, 460V 3Ph 3132-755 |
| 60 HP |
8 in |
8 in, 460V 3Ph 3132-766 |
| 75 HP |
8 in |
8 in, 460V 3Ph 3132-767 |
| 100 HP |
8 in |
8 in, 460V 3Ph 3132-768 |
Motor part numbers are 460V three-phase Baker motors of the matching size; other voltages are on the motor listings. Sources: Pumps by Baker catalog (Sept 2025, rev 3/26), pp. 173-174; Baker Pumps and Accessories price list, effective 7/1/2026.
Before You Buy — The Limits That Decide the Fit
| Motor |
Baker submersible motor of the same horsepower, sized to the bracket: 6 in and 8 in |
| Motor control |
Three-phase: starter kit or drive. Single-phase three-wire: control box |
| Well size |
8 in pump end; check the casing clears the pump end, motor and cable |
| Pairing |
One pump end per motor, one pump per well |
Materials of Construction
| Discharge, valve cone, top and bottom diffusers, diffusers |
Stainless steel 304 |
| Impellers, impeller rings, split cones and nuts |
Stainless steel 304 |
| Valve seat, upper and lower bearings, neck rings |
Stainless steel 304 / NBR rubber |
| Bearing |
NBR rubber |
| Pump shaft |
Stainless steel 431 |
| Coupling, strainer, suction interconnector, strap, nut, cable guard |
Stainless steel 304 |
| Stop ring spacing washer |
PTFE / CF |
Source: Pumps by Baker catalog (Sept 2025, rev 3/26), p. 173.
