Udor Pump Parts and Rebuild Kits

Udor triplex pumps rarely die outright. They wear through their consumables, and the crews that know this keep a seal kit and a valve kit on the truck. This collection holds the UD-numbered kits, ceramic plungers, retainers, and rail hardware for the Udor C, CK, G, GK, M, MK, and P series pumps we sell. Two minutes on the phone at 301-519-9274 with your pump model plate and we will name the exact kit you need.

Find the Right Udor Pump Part in Three Steps

Step one, read the model plate on the pump crankcase. The letters tell you the series, and the series decides which kit family fits. Step two, know your plunger size. Udor builds these pumps around 15mm, 18mm, 20mm, 25mm, and 28mm ceramic plungers, and a 20mm seal kit will not seal an 18mm plunger no matter how hard you push. The size is in the pump spec sheet, or measure a plunger once the head is off. Step three, pick the kit type that matches the wear you are seeing, which the next section walks through. Guessing costs a week of shipping. Reading the plate costs nothing.

Valve Kit, Seal Kit, or Retainer Kit?

Each kit type answers a different symptom. Valve kits cure pressure loss and pulsing when the plungers and seals still look healthy, because the little spring-loaded check valves foul and wear long before anything else. Seal kits stop water dripping from the weep holes and fix a pump that will not hold pressure after long bypass time. Brass retainer kits come into play when seals keep failing early, since worn retainers let the packing stack shift and chew itself up. Plunger o-ring kits are the cheap insurance you install any time the head comes off. And if a plunger shows scoring or a chipped ceramic edge, replace it, because new seals riding a scarred plunger die in weeks.

Udor Kit Lookup

Plungers also come in 15mm, 20mm, 25mm, and 28mm. Call for current availability before you schedule the rebuild.

From the Field

Soft wash guys run Udor pumps hard, and the rebuild pattern is consistent. Valves foul first, especially on rigs pulling from tanks that collect grit. Seals go second, and the tell is that faint drip line under the manifold at the end of the day. When a customer comes back for the same seal kit twice in a season, we stop selling him seals and start talking retainers and plungers, because something upstream is eating the packings. Check the oil sight glass every morning too. Milky oil means water is getting past the crank-side seals, and catching it early is the difference between a $98 kit and a crankcase job. Keep the pump oil fresh and half these visits never happen.

Related Collections

• Udor pumps
• All pressure washer pumps
• Pump oil
• Packing extraction tools
• Soft wash equipment
• AR pump parts
• CAT pump parts
• Comet pump parts
• General Pump parts
• Giant pump parts

Rebuilding on a deadline? Swing by the Gaithersburg counter and we will match parts against the pump itself.

Frequently Asked Questions

How do I identify which Udor pump I have?

Read the model plate on the crankcase. The letter code gives the series, such as CK, GK, MK, or P, and that series determines which valve, seal, and retainer kits fit. No plate? Send us a photo of the pump and we will identify it.

What size plunger does my Udor pump use?

Udor plunger pumps run 15mm, 18mm, 20mm, 25mm, or 28mm ceramic plungers depending on the model. The spec sheet lists it, and it is the one number you must have right before ordering a seal kit.

Should I replace plungers or just the seals?

Run a fingernail across each plunger. Smooth and glossy means seals alone will do. Any scoring, chips, or rough patches mean new plungers too, or the fresh seals will be gone within weeks.

Why does my Udor pump still lose pressure after new seals?

Usually the valves, not the seals. Worn check valves bleed pressure between strokes and mimic packing failure. Worn brass retainers letting the seal stack shift are the other common cause of a rebuild that does not hold.

Do Udor kits fit other pump brands?

No. Udor plunger sizes and seal profiles are their own. AR, CAT, Comet, General, and Giant each need brand-specific kits, which is why we keep separate parts collections for every brand we sell.

Can you match a kit if I only have the machine brand?

Usually. Many skid and soft wash builders spec Udor pumps, and we can work from the machine model to the pump underneath it. A photo of the pump plate makes it certain. Call 301-519-9274.