Graco 100188 Nut Heavy Hex

Graco 100188 Nut, Heavy Hex is a genuine OEM fastener designed for durability and precise fit in multiple Graco sprayers and systems.

Thread Size: 5/16-18 UNC
Used In: TexSpray GM 1030, GH 733, AquaMax Pressure Washers
Purpose: Secures frame and pump assemblies
Material: Heavy-duty steel, OEM specification

$12.26

Based on 0 reviews

Description

Graco 100188 — Nut, Heavy Hex (Genuine OEM)

Heavy-duty 5/16-18 UNC OEM fastener used across select Graco sprayers, texture rigs, and pressure-wash systems.

Compatible Machines

The Graco 100188 Nut, Heavy Hex is specified in official Graco parts lists for the following equipment families and assemblies:

TexSpray GM 1030 (parts list references 100188)
GH 733 Hydra-Sprayer (multiple qty of 100188 in frame/assembly)
AquaMax Belt-Drive Pressure Washers (e.g., Model 804599; includes 100188)
VPM Repair/Parts Assemblies (Graco service manual lists 100188)
Pressure Cup Assemblies (select Graco pressure cup parts lists include 100188)

What is the Graco 100188 Nut, Heavy Hex?

A heavy-hexagon nut engineered to OEM spec for Graco equipment. Compared to a standard hex nut, a heavy hex offers a larger cross-section for better clamping force and durability.

Key Specifications
Part Number	100188
Type	Nut, Heavy Hex (OEM fastener)
Thread Size	5/16-18 UNC (class per manual reference)
Typical Use	Secures structural and pump/frame assemblies on select Graco sprayers, texture units, pressure-wash systems, and accessories.

Fitment & Installation Notes

Match the thread (5/16-18 UNC) and grade to the original hardware.
Replace any worn or corroded nut/bolt/lockwasher sets together to maintain clamp load.
Follow torque guidance in your specific machine manual; re-check after first use.
Use genuine OEM hardware when assemblies operate under vibration or pressure.

Where You’ll See It in Manuals

In Graco IPLs (Illustrated Parts Lists), 100188 commonly appears around pump mounts, frames, brackets, or accessory plates. Quantity varies by model (e.g., 2–10 pieces in an assembly).

Frequently Asked Questions

No. It’s a heavy hex pattern—larger across flats and thicker than a standard hex, specified by Graco for higher clamp load and durability in certain assemblies.

Verified examples include TexSpray GM 1030, GH 733 Hydra-Sprayer, AquaMax Belt-Drive Pressure Washers, certain VPM service assemblies, and Pressure Cup assemblies. Always confirm against your exact model/serial.

It’s best practice to replace the mating hardware (e.g., 5/16" lockwashers/bolts) if worn or corroded to maintain proper clamp load and safety.

Quantities vary by model—manuals show counts from 1 up to 10+ in different assemblies. Check the Illustrated Parts List for your exact model.

Yes—100188 is a genuine Graco OEM part number appearing in multiple Graco manuals and IPLs.