Groco Marine Products
Groco Marine Products PTH-4000 Bronze Pipe-To-Hose Adapter Boating Maintenance
Connects pipe threads to hose with cast-bronze straight adapter in standard-flow design
- ColorTransparent
- Cast bronze construction resists marine corrosion
- Straight standard-flow design maintains efficient water passage
- NPT threads ensure secure pipe-to-hose connections
- New condition guarantees full material integrity
- California Proposition 65 listed for chemical awareness
Bronze Pipe-To-Hose Adapter for Marine Systems
The Groco PTH-4000 is a cast bronze adapter that connects NPT pipe threads to hose barbs in standard-flow plumbing. It is built for boat owners and marine technicians who need a reliable, corrosion-resistant transition fitting in raw-water or coolant circuits.
Replaces worn or incompatible threaded fittings
When an existing pipe-to-hose connection leaks, corrodes or restricts flow, this bronze unit restores a secure joint without reducing the internal diameter. The upgrade is worth it when the old fitting is damaged, made of dissimilar metal or cannot seal against the hose barb.
Fits NPT threaded ports and standard hose sizes
The adapter threads directly into a female NPT port and accepts a matching hose clamp connection, eliminating the need for extra reducers or bushings. Its straight cast bronze body frees up space in tight bilge areas while maintaining full flow through the circuit.
Highlights
- Cast bronze construction resists marine corrosion
- Straight standard-flow design maintains efficient water passage
- NPT threads ensure secure pipe-to-hose connections
- New condition guarantees full material integrity
- California Proposition 65 listed for chemical awareness
Specifications
| Color | Transparent |
|---|---|
| Brand | GROCO |
Questions about this item
What thread type does the PTH-4000 use to connect to a pipe?
The PTH-4000 uses NPT threads to connect to a pipe, matching standard tapered pipe fittings.
What is the common installation mistake with the NPT threads on this adapter?
Installers often overtighten NPT threads on bronze, risking cracks; tighten by hand plus one to two turns with a wrench.
How does the cast bronze body hold up in saltwater over time?
Cast bronze resists saltwater corrosion well; inspect annually for pink discoloration indicating dezincification and replace if found.
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