ESIESSENTIAL SHIPYARD INDUSTRIESEngine Survey · Cummins QSM11
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Engine Survey — Cummins QSM11 (marine)

A structured yard survey for the Cummins QSM11 (≈ 610–715 hp · 6-cyl turbo aftercooled (11 L)). Factory service due by hours, the full inspection with pick-the-fault detail, oil sampling, common-failure watch-outs and red-line stop items, optional compression. The overall result is computed from the findings, then emailed to the North or South desk.

6cylinders
Autoresult
→ deskemailed

🛥️Vessel & engine identity

Enter the hours — the factory-service section flags what should have been done.

⚑Vessel-specific known issues

Type the builder / model above — logged model-specific failures appear here to check (e.g. Ranger/Cutwater water ingress → transmission sensor & ECU).

Enter the builder / model above — known issues for that boat appear here.

🧰Tools required for this analysis

Bring the cart — have these before you start

Right tools on the first trip = a complete survey and no return visit. (Kaizen: stage the cart.)

  • Diesel compression tester + injector/glow-port adapter — for the optional compression test
  • Feeler gauge set — valve clearance to factory spec
  • Borescope / inspection camera — cylinders, aftercooler core, mixing-elbow bore
  • IR / laser thermometer — per-cylinder exhaust & cooling temps
  • Multimeter / clamp meter — charging, starting, grounds
  • Boost & exhaust-backpressure gauge (manometer) — turbo boost & restriction
  • Coolant refractometer / tester — glycol strength; raw-water salinity
  • Oil sample kit — pump, bottles, labels + a NEW pickup tube — use a fresh pickup tube per engine so samples don’t cross-contaminate; port & starboard
  • Inspection mirror, light & basic hand tools — access & visual
  • Cylinder leak-down tester (optional) — isolate a weak cylinder

Bring INSITE / diagnostic reader for fault codes; check the fuel shutoff solenoid first on a crank-no-fire; pop-off & inspect the aftercooler.

🛠️Factory service due — by hours

Milestones at or below the hours are flagged DUE. Mark whether each is Present in the records — a missing one counts as a maintenance item.

250 h / annualDUE at 250 h
Engine oil & filters, fuel filters / separator, sea-water impeller, belt, coolant / SCA check, anodes.
500 hDUE at 500 h
Aftercooler pop-off inspect, turbo inspect, hoses & clamps, air filter.
1000 hDUE at 1000 h
Aftercooler service, heat exchanger, injectors inspect, coolant / SCA service.
1500 hDUE at 1500 h
Valve lash & injector adjust; injection timing / STC per Cummins.

📋Factory survey checklist

Flag an item and pick the exact fault (or write it in).

🔧General engine survey

Belts, tensioner, running test, smoke, leaks — pick the fault on any flag.

⚙️Driveline — mounts, gearbox, coupling & shaft seal

Motor mounts & vibration, in/out of gear, shift resistance, coupling out to the shaft seal.

Mounts & vibration

Gearbox / transmission

Coupling out to shaft seal

🧪Fluid analysis — oil & coolant

Oil sample numbers (port/stbd), coolant colour vs the maker’s spec, and test-strip results.

Oil sampling

Coolant

📚Service records

⚠️Common failure watch-outs

Universal marine-diesel checks plus this engine’s known weak points — each with the standard it touches.

Why these matter

These common-issue checks catch the problems that become callbacks — and they are the honest upsell: the customer sees exactly what needs doing and leaves with a better, more reliable engine.

Universal · Leaks — oil, fuel, coolant, exhaust

Walk the whole engine: weeping covers/seals, oil cooler, fuel at the filters/injectors, coolant at hoses/pump, and exhaust soot at the elbow. Small leaks are a cheap fix now and a callback later.

⚓ Fuel → ABYC · Wet exhaust → · An exhaust leak is a CO hazard →
Universal · Oil in the turbo intake / charge air

Pull the intake / intercooler hose and look for pooled oil — turbo shaft-seal wear or heavy blow-by pushing oil into the charge air. It fouls the aftercooler and robs power; the classic ‘looked fine until it wasn’t.’

⚓ Engine maker / SAE — charge-air integrity
Universal · Belts & tensioner

Glazing, cracks, fraying, black dust and correct tension; check the tensioner / idler bearing. A $30 belt caught here beats a no-charge or an overheat on the water.

⚓ Rotating-machinery guarding → ABYC ; tension to engine-maker spec
Universal · Hoses & clamps

Squeeze every hose — hard, cracked, soft or swollen; wet-exhaust & raw-water hose hardens with heat and age. All-316 clamps, doubled below the waterline. The cheapest failure to prevent.

⚓ Wet-exhaust hose → ABYC (SAE J2006) · Raw-water / seacock hose → — double-clamp, all-316
Universal · Raw-water path & impeller

Impeller vanes (full set, cracks, missing pieces gone downstream), pump cover/cam wear, strainer and flow at the exhaust — the number-one overheating cause.

⚓ Seacock / intake → ABYC ; pump → engine maker
Universal · Corroded / loose electrical

Green-white corrosion on terminals, chafed harness, loose grounds and battery connections — intermittent faults and hard starts start here.

⚓ ABYC — connections, grounds & over-current protection
Universal · Motor mounts

Cracked or collapsed mounts, oil-soaked rubber, movement under load — the root of vibration and seal / coupling wear.

⚓ Engine mounting → ABYC · Shaft alignment →
Universal · Coolant & anodes

Coolant strength and condition and the heat-exchanger pencil anodes — neglected coolant and spent anodes quietly eat the cooling system.

⚓ Engine maker; galvanic/anode context → ABYC
QSM11 · Fuel shutoff solenoid — no-start / mystery shutdowns

A failing internal fuel shutoff solenoid is the classic QSM11 no-start and unexplained-shutdown cause (fail-safe cuts fuel). Check it first on crank-no-fire.

⚓ Fuel → ABYC ; electrical →
QSM11 · Aftercooler — pop off & service

Service / pop-off the aftercooler ~1000 h (or 6–10 yr) — debris/corrosion into the aftercooler damages the engine.

⚓ Engine maker; charge-air → context
QSM11 · Turbo — inlet-nut back-off & wheel play

Lag on run-up, backed-off inlet-turbine nuts, wheel resistance/play.

⚓ Engine maker
QSM11 · SmartCraft / ECM electronics & shutdowns

Blank SmartCraft screen and shutdowns that clear after ~30 min — check harness, grounds, sensors and fault codes.

⚓ Electrical → ABYC
QSM11 · Cooling — end-cap corrosion, HX, impeller, coolant / SCA

Coolers assembled dry → heat-exchanger/aftercooler end-cap corrosion; plus clogged HX, worn impeller and coolant/SCA level — the usual overheats.

⚓ Seacock → ; maker

⚓Standards this survey touches

The ABYC & maker references behind the flags above — thoroughness the customer can see.

ABYC P-1-2025Marine wet-exhaust systems — mixing elbow / riser bore, hose (SAE J2006), backpressure, water intrusion.
ABYC H-33-2021Diesel fuel systems — lines, filters/separator, connections and leaks.
ABYC E-11-2025AC & DC electrical — wiring, grounds, connections, over-current protection, charging.
ABYC H-27-2021Seacocks, thru-hulls & raw-water hose — intake path, double-clamping.
ABYC P-6-2021Propeller shafting — shaft, coupling, alignment, stuffing box / seal, bearings.
ABYC P-4Inboard engines & transmissions — mounting, guarding, controls.
ABYC A-24-2025Carbon-monoxide detection — an exhaust leak is a CO hazard in the accommodation.
ABYC E-2-2025Cathodic protection / bonding — anodes on the cooling & underwater metals.
Cummins service manualPeriodic maintenance, clearances, torque and manufacturer bulletins for the QSM11.

Sources: Cummins QSM11 marine maintenance (aftercooler ~1000 h; fuel shutoff solenoid; SmartCraft); marine-service best practice.

🚫Red-line — immediate-service flags

Check any that are present. Any one flags the survey for immediate service.

🚫 IMMEDIATE SERVICE REQUIRED — one or more red-line conditions checked. Do not return to service without addressing them.

📈Compression test (optional)

Optional — recorded and marked present only if performed.

Port / single (psi)

Starboard (psi, twin)

📝Overall result (auto)

The result is derived from the survey, not a judgment call.

Overall: —

Computed from the findings above — red-line = immediate; otherwise significant vs maintenance issues set the result. Not a manual rating.

📨Send survey to the desk

Pick the Yard below, preview, then send — the full report emails to that desk.