Graco 218036 Piston Valve - Aftermarket Replacement | Bedford 58-1775

Service-grade piston valve that restores prime and seal in Graco pump lowers used on Ultra 333/433/1000 and GM3500 platforms. This aftermarket part replaces OEM 218036 with Bedford reference 58-1775 for a direct, bench-friendly swap.

Aftermarket Precision-Machined Industrial Duty

Why Choose This Piston Valve

  • Controls check action for steady prime and pressure build.
  • Machined seat interface supports repeatable sealing.
  • Direct interchange with the OEM reference for quick turnarounds.

Finish & color: Bright metal (satin steel) with neutral hardware; minor accent colors may vary by lot.

Typical Compatibility

  • Ultra 333 / Ultra 433 airless sprayers (designated removable-sleeve lowers).
  • Ultra 1000 / Ultra Plus 1000 models that list 218036 in the parts breakdown.
  • GM3500 sprayers using the corresponding lower assembly with this valve callout.

Verified against published parts references for Ultra Plus 1000 and GM3500 families; always confirm in your IPL.

What This Product Fits

  • Graco Ultra 333.
  • Graco Ultra 433.
  • Graco Ultra 1000 / Ultra Plus 1000.
  • Graco GM3500 (see pump lower diagram/parts list).

If your Illustrated Parts List specifies 218036 for the piston valve, Bedford 58-1775 is the matching aftermarket option.

Technical Specifications

Aftermarket Bedford 58-1775
OEM Graco 218036
FitsUltra 333 / 433 / 1000 (Ultra Plus 1000), GM3500 lowers (verify by IPL)
TypePiston valve (check component for fluid section)
MaterialPrecision stainless/treated steel seat interface
FunctionRegulates inlet check to maintain prime, hold pressure, and limit bypass
PressureUse within the sprayer’s rated working pressure
BrandAftermarket by Bedford Precision Parts

Installation Notes

  1. Relieve pressure and isolate power/air per your model manual.
  2. Remove the lower; note valve orientation and seat condition.
  3. Clean the bore and mating seat; inspect rod/sleeve for scoring.
  4. Install the piston valve; torque components to specification.
  5. Prime at low pressure; leak-check, then verify stable build.

Real tip: Replace packings and inspect the intake valve during the same service to keep check timing balanced.

When to Rebuild / Replace

  • Slow prime or pressure decay after purge.
  • Drips or backflow at the lower despite good packings.
  • Pitting, nicks, or washout on the valve/seat.
  • Irregular spray pattern linked to unstable pressure build.

Bedford vs OEM Comparison

FeatureBedford Aftermarket (58-1775)OEM (Graco)
InterchangeDirect replacement for 218036 in listed Ultra/GM lowersFactory original 218036
BuildPrecision-machined metal, service-readyOEM-specified construction
FitmentUltra 333/433/1000, GM3500 (per IPL)Ultra 333/433/1000, GM3500 (per IPL)
AvailabilityIf in stock, ships from Bedford Precision Parts in Bedford Hill, New York.Ships via Graco distribution

FAQs

Yes. Bedford 58-1775 is the aftermarket equivalent for the OEM piston valve 218036 used on select Ultra and GM lowers. Confirm with your IPL before ordering.
Graco Ultra 333, Ultra 433, Ultra 1000/Ultra Plus 1000, and GM3500 models that list 218036 in the parts list.
Service-grade stainless/treated steel for the valve body and seat interface to support consistent sealing.
Work clean, check the mating seat, lightly lubricate as specified, torque to spec, and verify prime at low pressure before returning to service.
If available, orders ship from Bedford Precision Parts in Bedford Hill, NY with your chosen carrier.