Please wait while we process your order...

Product successfully added to your cart.
Cart Image

Quantity in Cart: 1

Continue Shopping Shopping Cart
Item removed from Cart
X
 
×
📢 From June 8th to 25th, phone support will be limited. For assistance, please email us and we will respond as promptly as possible. Orders will continue to be processed normally.

sprayersandparts Logo

Product Image

Graco 166033 Nut Coupling

Genuine Graco 166033 — Nut, Coupling for lower/displacement pump assemblies; secures the rod connection for reliable, high-pressure operation.

  • Fits: Monark 5:1 airless pumps (drum-mount)
  • Also used on stainless drum-type displacement pumps
  • Compatible with EFP-350 XT electric feed pump (lower)
  • Material: stainless steel; corrosion-resistant
  • Verify against your model’s parts manual before ordering

$105
0
Based on 0 reviews
5 ★
0%
4 ★
0%
3 ★
0%
2 ★
0%
1 ★
0%

Overview & Fitment Details

Compatible Machines

This part is used in the lower/displacement pump section on the following Graco equipment.

  • Graco Monark 5:1 Airless Spray Pumps (drum-mount variants)
  • Graco Stainless-Steel Displacement Pumps — Drum Type
  • Graco EFP-350 XT Electric Feed Pump (lower pump assembly)
  • Other Graco displacement pump assemblies that specify part no. 166033

Key Information

Genuine Graco 166033 — Nut, Coupling. Designed to couple and secure the displacement rod/pump components, maintaining alignment and load under high pressure.

Part Number 166033
Official Name Nut, Coupling
Function Joins/locks the displacement rod and related pump components for reliable, leak-free operation.
Typical Location Lower / displacement pump assembly
Material Stainless steel (corrosion-resistant)
Category Pump hardware & fasteners
Compatibility Note Always verify against your pump’s parts manual; some variants use different coupling hardware.

When to Replace

  • Visible thread wear, rounding, or cross-threading
  • Difficulty maintaining rod alignment or repeated loosening under load
  • Corrosion that could compromise clamping force

Frequently Asked Questions

Check the exploded parts diagram for your exact model and look for part no. 166033 in the displacement/lower pump section. If your manual lists another coupling nut number, use that specific part instead.

Clean and inspect mating threads; replace damaged rods or connectors. Hand-start to avoid cross-threading, then torque to spec in the service manual. Re-check tightness after first use cycle.

Unusual vibration, loss of prime, rod misalignment, or visible looseness after short run time suggest the coupling nut or its mating parts are worn and should be replaced.

Payment Method   Payment Method   Payment Method   Payment Method 

ADDRESS