The 300-hourserviceyour engines are due for.

Why 300 hours is the interval that matters

Manufacturers publish 20-hour, 100-hour and 300-hour schedules. The 100-hour is largely fluids and filters. The 300-hour is where the wear items that actually kill engines get addressed: the water pump impeller that has been heat-cycling for three seasons, the thermostat that's starting to stick, the valve clearances that have drifted, the anodes that are two-thirds gone.

In South Florida the calendar side of that rule bites harder than the hours. Salt intrusion, constant humidity and year-round use mean a boat with 180 hours and three years on the clock is often in worse shape internally than a freshwater boat at 300. We service on whichever comes first, and we tell you honestly which parts still have life in them.

What's included in a 300-hour service

• Engine oil and filter change (4-stroke), oil analysis available
• Lower unit / gearcase oil drain, inspect for water or metal, refill
• Water pump impeller, housing, wear plate and gaskets replaced
• Thermostats and poppet valve inspected or replaced
• Spark plugs replaced, coils and leads inspected
• Fuel filters — engine-mounted and water-separating — replaced
• Valve clearance inspection and adjustment per manufacturer spec
• Anodes inspected and replaced where under 50%
• Steering, tilt/trim fluid, hydraulic lines and rams inspected
• Battery load test, terminal cleaning, charging output check
• Corrosion audit: powerhead, mid-section, bracket, hardware
• Diagnostic scan and fault-code read on digital engines
• Sea trial or run-up with WOT RPM verification

What a proper service looks like

1. 1. Scan and baseline

   We pull engine hours, fault history and fuel-flow data before touching anything, so we can compare against how the engine runs afterwards.

2. 2. Fluids and filters

   Gear oil is drained into a clean pan and inspected first — milky oil or metal flake changes the whole conversation before more money goes into the job.

3. 3. Water pump

   Lower unit dropped, impeller kit replaced with housing and wear plate, shift linkage checked, seals inspected for the early signs of a leak.

4. 4. Ignition and valves

   Plugs out and read (they tell you how the engine has been running), valve clearances measured cold and shimmed if out of spec.

5. 5. Corrosion and anodes

   Every anode measured, bonding checked, and any stray-current symptoms flagged — a boat that eats anodes has an electrical problem, not an anode problem.

6. 6. Run-up and report

   Engine run under load, WOT RPM checked against prop spec, then you get a written report with photos and a prioritised list of anything we found.

How this fits with detailing

We're a detailing and preservation company first, and engine maintenance is preservation. Corrosion doesn't respect the line between the cosmetic and the mechanical: the same salt film that dulls your gelcoat is sitting on your bracket bolts, your trim rams and your engine mounts. Boats on our recurring wash programs get the engine bay rinsed, dried and treated with corrosion inhibitor every visit, which is why they show up to a 300-hour with dramatically less to fix.

What it costs

Engine service is quoted per engine, per make and model, because parts kits and labour hours vary widely between a 90hp four-stroke and a 425hp V8. Pricing below is a working range for planning — you get a firm number with parts itemised before we start.

• 300-hour service — single outboard up to 200hp
  $850 – $1,350 per engine
• 300-hour service — outboard 225hp+
  $1,200 – $1,900 per engine
• Sterndrive 300-hour incl. bellows inspection
  Quoted after inspection
• 100-hour interim service
  from $425 per engine

Questions people actually ask

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