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Coordinate free equipment or component pick-up when applicable.
24-Hour Rush Repair
Pump bench · Graco
Graco Pump Repair in Fontana
Graco pumps move the fluids other pumps would rather not touch - paints and coatings in finishing shops, adhesives and sealants in manufacturing, chemicals, inks and sanitary fluids, all pushed by air-operated double-diaphragm and piston transfer pumps that stall-proof, self-prime and run dry without complaint. When a Graco pump does falter, the symptoms are rhythmic: a stroke that hangs at changeover, output that pulses unevenly, air blowing through without moving fluid. LA Trucks and Tractors repairs Graco pumps at our shop at 14166 Whittram Ave, Fontana, CA 92335. We are an independent repair shop, not a Graco dealer. Diaphragm, piston and transfer pumps are stripped on our bench, their air motors and fluid sections measured and renewed as required, and every rebuilt pump is cycle-tested on air before it returns to the plant. Paint and powder shops, RV and trailer builders, sealant and adhesive applicators, printers and chemical blenders across the region all lean on Graco pumps that are expected to move difficult fluids without a dedicated operator watching them.
Pump bench · Graco
Diaphragm pumps diagnosed at the air valve as much as the fluid end
Half of all diaphragm pump trouble lives on the air side, and it is the half most often missed. A worn main air valve or pilot mechanism makes the pump stall mid-stroke, short-stroke, or favour one side, while the fluid end gets blamed and re-kitted in vain. The fluid section has its own ledger: diaphragms fatigued or chemically attacked, ball checks and seats worn until the pump slips back each stroke, and housings eroded by abrasive fillers in coatings. Our teardown inspects both halves in sequence - air motor valve wear, shaft seals and pilot operation, then diaphragm condition, check-ball and seat sealing, and manifold and housing surfaces - and the quote separates them plainly. Renewals use materials matched to the fluid you actually pump, because a diaphragm compound that shrugs off paint solvent may surrender to the chemical in the next drum, and that conversation is part of doing this repair once. We also service the supporting cast that decides whether a Graco pump performs: regulators and air preparation are checked when a pump arrives with starvation symptoms, suction and discharge hose restrictions are flagged from the flow test, and wetted-material compatibility is reviewed against every fluid the pump may meet, including the cleaning solvent that so often attacks diaphragms the product never harmed. Pumps used on spray and finishing duty are tested for smooth changeover at low cycle rates as well as full flow, because finish quality suffers from the surge a worn air valve introduces long before output falls.
Brands we serviceGracoAll-FloVikingBlackmerWaukeshaAmpcoGardner Denver
Graco Pump Repair in Fontana · Fontana, CAA stalled pump holds up the whole finishing line
Bring Graco work in Monday to Friday between 6 AM and 5 PM, or call the round-the-clock rush line - (800) 821-3404 or (949) 400-2937, staffed 24 hours a day, 365 days a year - when a coating line is standing. Quotes are free, pick-up and delivery are free, and you will speak with John Clark, who will tell you whether your pump needs an air-side overhaul, a fluid-end kit, or both, with the findings to back the recommendation. Small pumps get the same evidentiary treatment as large ones here; the rhythm fault is in the measurements. Shops standardising on one Graco model across several lines can hold a single rebuilt spare with confidence - each unit leaves with its test behaviour recorded, so a swap is a known quantity.
- Graco air-operated double-diaphragm pump rebuilding
- Air valve, pilot and shaft seal overhaul
- Diaphragm renewal in compounds matched to your fluid
- Ball check and seat renewal for full, even output
- Air cycle testing through the full stroke range
Our 8-step repair process
A clear path from the first call to a tested component or machine returned to work.
Inspection
Disassemble and evaluate the complete failure.
Photos & video
Document condition and findings for a clear repair conversation.
Repair quote
Define the recommended work and quote before proceeding.
Approval
Confirm scope, urgency and the practical path forward.
Manufacturing
Machine, weld, rebuild or reverse engineer required components.
Testing
Verify operation and workmanship before release.
Shipment
Return the completed component or equipment to service.
Frequently asked questions
My Graco pump stalls mid-stroke and restarts when tapped. What is failing?
That classic symptom is a worn air distribution valve or pilot, not the fluid end. We overhaul the air motor, renew its seals and verify changeover on test, which cures the stall without unnecessary fluid-end parts.
Can you match diaphragm material to the chemical we pump?
Yes - material compatibility is decided at quote time from the fluid you name. We fit diaphragm, ball and seat compounds suited to that service so chemical attack does not schedule the next rebuild.
Our Graco pump's output has become uneven between strokes. Where do you look first?
Uneven output usually means one side's checks or diaphragm are underperforming, or the air valve is favouring one changeover. We test each side's delivery on the bench, then open the side the evidence indicts rather than kitting the whole pump on suspicion.
Related services
Emergency breakdown? Call the 24-hour rush line.
(949) 400-2937Schedule service or open a repair order
Request a service call.
Include the make, model, symptoms, location, urgency and preferred service time. Your details open in a text to John so you can review them before sending.