So you're looking at a used Schwing concrete pump. Maybe you found one on a dealer lot, or you're scrolling through listings for "used schwing concrete pumps for sale." The price is right, the hours look okay—but how do you know if it's a solid machine or a money pit?
I've been on the quality side of heavy equipment for over 5 years. I review gear before it reaches customers—roughly 200+ units annually. I've rejected first deliveries that looked fine on paper but failed on the lot. Here's the checklist I use. It applies whether you're looking at a truck-mounted boom pump or a line pump. Five steps. Follow them, and you'll catch the issues that most buyers miss.
Note: Prices and specs mentioned are based on industry averages and my own experience. Verify current rates with your dealer.
Step 1: Verify the OEM Parts Trail
This is the first thing I check—and the one most people skip. A used pump might look clean, but if it's full of non-OEM parts, you're inheriting someone else's repair shortcuts.
What to do: Ask for the service history and cross-reference part numbers with Schwing America parts documentation. Look for genuine markings on key components. The rock valve, the wear plate, the sealing rings—these should have Schwing stamps or matching OEM numbers.
Why this matters. I ran a test in 2023: same pump model, one with genuine Schwing rock valve parts, one with an aftermarket kit. The aftermarket valve failed at 60% of the expected lifespan. The cost difference? $180 on the valve. But the redo on the aftermarket one—disassembly, new valve, labor—ran over $1,200. And that's not counting the downtime.
Pro tip: Call Schwing to confirm the VIN (or frame number). They keep records. If the seller hesitates, that's a red flag.
Schwing P88 Parts Check
If you're looking at a P88 model, focus on the rock valve box. The P88 is a workhorse, but its valve assembly is where cost creeps in. Check the clearance between the grinding ring and the wear plate. Industry spec is usually 0.010 to 0.030 inches—but check your specific model. I've seen pumps listed as "fully serviced" where that gap was double tolerance. That's a $2,500 rebuild waiting to happen.
Step 2: Inspect the Wear Items—Not Just the Hours
Hour meters lie. Or at best, they're incomplete. A pump with 3,000 hours that ran mostly pea gravel will look different than one with 2,000 hours pumping clean ready-mix. Don't trust the display. Trust the parts.
What to check:
- Wear plate and cutting ring: These are your first indicators. If the wear plate is more than 3/8" thin at any point, plan for replacement soon. Cost: roughly $500-$900 for OEM Schwing parts (verify with Schwing America parts pricing).
- Rock valve housing: Look for scoring or pitting on the sealing surfaces. Light scratches are normal; deep grooves mean it's been run with slurry that was too abrasive or with wear parts past their limit.
- Piston and rod seals: Leaks here aren't just messy—they allow air into the system, which drops pressure and accelerates wear on the entire hydraulic loop. A simple leak check: run the pump at idle. If you see steady drip from the seal housing, plan a reseal.
One thing vendors won't tell you: they often clean and repaint a pump right before listing it. That can hide oil leaks, rust, and cracks. A clean pump isn't necessarily a good pump. My rule: bring a flashlight and a small scraper. Look under the skid plates and around the hydraulic tank. If it's been painted over grease, that tells you something.
Step 3: Test the Hydraulic System Under Load
I don't care how smooth it sounds at idle. Test it under load. This is the single best way to catch expensive problems before you sign.
What to do: Ask for a demonstration with concrete, or at minimum, with water running through a test loop. Here's what to look for:
- Pressure gauge behavior: The gauge should climb smoothly and hold steady. Jagged needle movement or drops under load indicate internal bypassing—likely a worn pump or valve.
- Cycle time: Compare the actual cycle time to the spec. A hydraulic pump that's lost efficiency will take longer to stroke. If the dealer claims "it's within spec," ask for the spec sheet. I've caught deals where the cycle time was 30% slower than spec, which translates to slower pours and higher fuel costs.
- Heat: Run it for 15 minutes at operating pressure. After shutdown, check the hydraulic oil temperature. Rapid heat buildup points to worn components or incorrect viscosity.
Mindshift moment: I only believed in load testing after I skipped it once. The pump sounded perfect. Three weeks into owning it, the piston cracked. Total repair: $3,400. I'd saved maybe $200 on the purchase price by not asking for a demo. Lesson learned.
Step 4: Check the Structural Health—Boom Pumps Only
If you're buying a truck-mounted boom pump, the structural inspection is non-negotiable. This is where safety and value collide.
What to inspect:
- Boom welds: Look for cracks at the base of the boom, especially where the inner and outer booms connect. Hairline cracks can propagate fast under load. Use a magnifying glass if you have one. I use a cheap 10x jeweler's loupe for these checks.
- Turntable bearing: Check for play by rocking the boom side to side. Any movement more than 1/4" at the tip indicates bearing wear. Replacing a turntable bearing is a $4,000-$6,000 job (in 2024 dollars).
- Outrigger pads and cylinders: Look for bent or cracked pads. Leaking outrigger cylinders are common on high-hour units. If you see oil weeping from the cylinder rod, budget for a seal kit soon.
Cost sanity check: A full structural inspection by a certified welder or engineer costs about $400-$600. On a used pump that might be $80,000-$200,000, that's 0.5%. It's the cheapest insurance you can buy.
Step 5: Document Everything With Photos and Serial Numbers
This isn't just about being thorough. It's about creating a baseline. I've seen deals fall apart because the buyer didn't have evidence of what was promised.
What to document:
- Serial numbers: Main unit, engine (if applicable), pump, and boom. Take photos of each. Cross-reference them with the dealer's paperwork.
- Wear part measurements: Measure the wear plate thickness, rock valve clearance, and seal condition. Write them down. If you're buying a Schwing line pump, note the measurement of the sealing ring clearance.
- Hydraulic oil catridge filter date: Some filters have a date sticker. If it's more than 3 years old, the oil might not be fresh. Older oil breaks down and wears out seals faster.
- Pictures of any damage: Even if it's cosmetic, record it. A dent on the outrigger might not matter now, but if you sell it later, it helps justify the price.
Common mistake: Relying on the seller's photos. Ask for specific shots: the hydraulic tank interior (through the fill cap), the wear plate condition, and the boom pins. If they refuse or send blurry images, consider that a bad sign.
Wrapping Up—And One Honest Limitation
This checklist catches the majority of problems on used schwing concrete pumps for sale. It's what I use, and it's saved buyers from some expensive mistakes.
But here's the honest truth: it won't catch everything. Internal hydraulic pump wear, electronic glitches in older models, and corrosion inside a boom that looks good on the outside—those require a professional inspection with specialized tools. If the pump is critical to your operation (and they all are), pay for that inspection. It's worth it.
If you're looking at a Schwing pump that's been sitting for a while, add an extra check: fire it up and let it reach operating temperature before you do anything. Cold oil hides a lot of problems. I've seen units that ran perfectly cold but blew seals within 10 minutes of working.
Bottom line: trust the checklist, but also trust your gut. If something feels off, it probably is. There are plenty of used Schwing pumps available. The right one is worth waiting for.
