Yamada 771231 Ball Guide, polypropylene for NDP-25
The Yamada 771231 is the genuine ball guide for NDP-25 Series pumps with polypropylene wet ends. It sits above the check ball and limits how far the ball can lift, keeping it captive over its seat so that it drops back onto the same spot every time.
They also crack. The ball strikes the guide at the top of its lift on every stroke, and a plastic guide that has been through a lot of cycles, or a cold start with a thick product, can fracture. Pieces of a broken guide travel downstream and jam another check valve, so it is worth looking at the guides carefully whenever the wet end is open.
Key Features
- Genuine Yamada replacement ball guide
- Material: polypropylene
- Fits NDP-25 Series pumps with polypropylene wet ends
- 4 per pump in a standard pump build
- Keeps the check ball captive and centered over its seat
- Replace together with the balls and seats
Applications
- NDP-25 Series pumps with polypropylene wet ends
- Wet end rebuilds and liquid side overhauls
- Replacing a cracked or eroded guide
- Restoring even check valve wear
- Service after abrasive or solids laden duty
- Marine, industrial and chemical transfer applications
Specifications
- Brand: Yamada
- Manufacturer: Yamada America
- Manufacturer Part Number: 771231
- Part Type: Ball Guide
- Material: Polypropylene
- Fits: NDP-25 Series pumps with polypropylene wet ends
- Quantity Used: 4 per pump
- Series Port Size: 1 in on the NDP-25 Series
- Condition: New
Frequently Asked Questions
Q: Does the guide material have to match the wet end?
It should be compatible with the fluid and with the temperature. Yamada supplies guides in materials matched to each wet end build for exactly that reason.
Q: How often should guides be replaced?
Inspect at every liquid end service and replace when the ball contact points are visibly worn or any opening has eroded. On abrasive duty that is often every second ball and seat change.
Q: Are guides handed?
Yes, they fit one way round over the seat. Note the orientation of the old ones before removing them.
Q: What happens if a guide breaks?
The ball loses its limit stop and the broken pieces travel with the flow. They usually end up jammed in another check valve or in the discharge manifold, so a pump that suddenly stops delivering after a guide failure needs a full wet end inspection.
Not sure this is the right part? Send us a Picture of the Pump Plate on your pump and the CLR Marine team will confirm the correct ball guide.
CLRMarine
