Product Details & Fitment – Graco 103778 Pipe Plug (1/2-14 NPTF)
Compatible Machines
This OEM plug is used across multiple Graco sanitary and industrial pump systems. Confirm your parts diagram before ordering.
- SaniForce 1590 High-Sanitation Diaphragm Pumps (used as plug in the center/air section)
- SaniForce 3250 High-Sanitation Diaphragm Pumps (plug for leak-detector/air section ports)
- SaniForce 2150 models for Ram-mounting (center section uses this plug)
- E-Flo SP Electric Pump Systems (check-valve block/manifold assemblies include this plug)
What is the Graco 103778 Plug, Pipe, HDLS?
A genuine Graco pipe plug used to seal 1/2-inch NPTF female ports in pump center sections, leak-detector holes, and manifold/check-valve blocks on select systems. Typical functions include capping unused ports and closing inspection/leak-detector openings per OEM specifications.
Specifications
| Part Number | 103778 |
| Description (OEM) | PLUG, PIPE, HDLS – 1/2-14 NPTF (Dryseal) |
| Thread / Size | 1/2-14 NPTF (fits 1/2″ NPTF female ports) |
| Type / Function | Threaded pipe plug for sealing ports (center section, leak-detector holes, manifolds) |
| OEM Status | Genuine Graco replacement part |
Installation & Fitment Notes
- Depressurize equipment, follow Graco lock-out procedures, and clean the port before installation.
- Thread in by hand to start; tighten per equipment torque guidance to avoid thread damage.
- Only use where manuals/parts lists specify 103778 or a 1/2-14 NPTF plug.
Frequently Asked Questions
It’s a 1/2-14 NPTF (Dryseal) pipe plug designed for 1/2″ NPTF female ports.
Verified examples include SaniForce 1590 and 3250 high-sanitation diaphragm pumps, certain SaniForce 2150 (Ram-mount) configurations, and specific E-Flo SP electric pump systems. Always confirm against your model’s parts list before ordering.
The sanitary/industrial manuals list the part number and function but do not always state material. If your application requires a specific material, consult the manual for your exact model or contact Graco/distributor support with your model and serial number.
Use the OEM part where specified. Even with matching 1/2-14 NPTF threads, non-OEM plugs may not meet the sealing, depth, or sanitation requirements of the system.
Common locations include the air/center section (inspection or service ports), leak-detector holes on high-sanitation pumps, and check-valve block/manifold ports in electric pump systems, as directed by the model’s service manual.
