Wacker Neuson 5100075633 3/8-16x1-1/4 Hex Flange Screw Grade 5

The Wacker Neuson is a genuine OEM 3/8-16x1-1/4 Hex Flange Screw Grade 5 designed for PDT3A, PDI3A, PDT2A, and PDI2A series diaphragm pumps. Sourced directly from Wacker Neuson, this fastener meets the exact material and dimensional specifications used in original production — no guesswork, no substitution. Verified fitment covers both standard and pump diaphragm variants across the PDT and PDI pump families, making it a direct swap with full confidence in the fit. Keep your pump assembly torqued to spec and performing the way it was built to with the correct OEM hardware.

Key Features

• Grade 5 Tensile Strength — Rated Grade 5 hardness means this screw handles the clamping loads and vibration stress typical in diaphragm pump assemblies without stretching or backing out.
• Integrated Flange Bearing Surface — The built-in flange distributes clamping load evenly across the mating surface, eliminating the need for a separate washer and ensuring consistent seating on pump housing joints.
• Genuine OEM Part — Supplied by Wacker Neuson as original production hardware, so thread pitch, grip length, and head dimensions match the tapped holes this screw was engineered to fit.
• Broad PDT & PDI Pump Compatibility — Fits PDT3A, PDI3A, PDI3A(I) Pump Diaphragm, PDT2A, and PDI2A(I) Pump models, covering a wide range of Wacker Neuson diaphragm pump configurations in a single part number.
• Maintains Proper Pump Assembly Integrity — A correctly torqued fastener at critical pump joints prevents fluid leaks, housing movement, and premature seal wear that a worn or incorrect screw would allow.

A hex flange screw is a structural fastener that combines a hex drive head with an integral flanged washer base, used to clamp pump housing panels, covers, and component mounting points securely together. In a diaphragm pump, these fasteners are subjected to continuous vibration and fluid pressure cycling, so the correct thread engagement and clamp load are critical to preventing joint loosening and leaks. When a fastener stretches, strips, or is replaced with an incorrect grade or size, it can compromise the seal between pump components — leading to fluid loss, contamination ingress, or accelerated wear on mating parts.

Part Details

Compatibility & Fitment

Verify Before You Order

Fitment is machine-number and revision-specific; always confirm your model and serial number against the fitment list.

Why Buy From DHS Equipment

Every part is verified against the manufacturer's part number before it ships, so what you order is what arrives. We carry parts from leading OEM brands and our own DHS Quality Parts line of professional aftermarket components. Need help finding the right part? Our team is available to confirm compatibility whenever you need it. Orders are processed fast to keep your jobs on track. We don't just sell parts. We keep you jobsite ready.

Questions? Contact our team at [email protected] or 866-611-9369 — DHS Equipment is here to help you maintain peak performance.