100‑Hour Engine Service and Major Inspection
Overview
Your boat works hard. Our 100 hour boat service is the major service interval designed to reset reliability, performance, and safety before the next stretch of run time. At ASFB Marine, this annual boat service level (or every 100 engine hours) goes deeper than routine maintenance: we update software, perform engine calibration, refresh critical wear parts, change fluids, and complete a bow‑to‑stern systems check so you can launch with confidence.
- Prefer to talk it through? Call (916) 737-2628. It’s the fastest way for our team to capture the right details and timing for your boat.
- New to our service packages? See the full program on our Services Overview page.
100‑Hour Service Checklist
This 100 hour service checklist reflects a comprehensive, major service for modern marine engines and rigging. Inclusions may vary slightly by make/model, but our core process covers:
- Software updates to the latest approved version
- Engine calibration to manufacturer specifications
- Change engine oil and replace oil filter
- Change transmission fluid
- Inspect V‑drive fluid, check for leaks, and add oil if needed
- Replace impeller (cooling system protection)
- Replace spark plugs
- Replace fuel filter or filters (as applicable)
- Clean oil filler cap
- Clean sea water strainer (when applicable)
- Clean flame arrestor
- Clean crankcase ventilation system
If we find anything outside spec during the inspection, we’ll explain options clearly before proceeding. Many owners also combine minor fixes or upgrades while the boat is already in the shop—ask us what’s efficient to bundle.
- Inspect distributor cap, rotor, and points (if applicable)
- Inspect and tension/retighten belts
- Inspect fuel system lines and connectors for leaks
- Inspect hoses for leaks and tighten as needed
- Inspect spark‑plug wiring and replace if needed
- Inspect engine alignment and engine mounts
- Grease rudder (when a zerk fitting is present)
- Lubricate throttle and shift‑linkage pivot points
- Tighten ground connection at the engine block
- Load‑test batteries
- Apply corrosion guard to engine and engine mounts
- Test‑run engine in shop and verify proper operation
Scheduling and what to expect
Ready to lock in a date? You can also request a service appointment and we’ll follow up to confirm details.
Why this major service matters
Looking for the mid‑interval package instead? Compare our 50‑Hour Engine Service to plan your year‑round schedule.
- Reliability first: Replacing the impeller, spark plugs, and fuel filters while refreshing all critical fluids protects your engine against overheating, lean conditions, and premature wear. This is foundational marine engine maintenance.
- Performance and efficiency: Proper engine calibration, clean ignition components, and updated software can smooth idle, improve throttle response, and maintain designed fuel economy.
- Long‑term value: Small issues multiply when left unresolved. A thorough 100‑hour cycle reduces the chance of mid‑season surprises and helps protect resale value.
- Warranty support: Following manufacturer maintenance schedules (and documentation) helps maintain eligibility for warranty coverage. ASFB Marine performs warranty work in‑house for supported brands.
Engines and components we service
We routinely service a wide range of marine power and driveline configurations. That includes outboards, inboards, and sterndrives, with attention to:
Transmission service and checks
V‑drive inspection, top‑offs, and leak checks (where equipped)
Cooling‑system integrity from the raw‑water pickup through the impeller and strainers
Throttle/shift linkage lubrication and smooth control feel
Electrical health via battery load‑testing and ground verification
If your configuration is unique, call us. We’ll confirm scope and any model‑specific steps before scheduling.
Add repairs or upgrades while you're in
The 100‑hour visit is a smart time to address small repairs or install planned upgrades so you’re not doubling up on downtime. Popular adds include:
Propeller repair or replacement (performance/efficiency checks)
Electrical troubleshooting or rigging improvements
Control and steering feel adjustments
Repower or re‑rig planning for the off‑season
Exploring more power or newer technology? Talk with our team about Engine Installation & Repower and the best timing for your boat.
100‑Hour Service FAQs
Need help deciding between intervals? Start at our Services Overview, compare options, then request a service appointment—or call (916) 737-2628 and we’ll build the plan together.
What's included in a 100 ‑ hour service?
This is our most in‑depth routine package. It includes software updates, engine calibration, engine oil and filter, transmission fluid, V‑drive fluid check/top‑off, new impeller, new spark plugs, fuel filter(s), cleaning of the oil filler cap, sea water strainer (if equipped), flame arrestor, and crankcase ventilation system; inspections of cap/rotor/points (if applicable), belts, fuel lines/connectors, hoses, plug wires (replace if needed), engine alignment/mounts; grease rudder (if zerk), lube throttle/shift pivots, tighten engine‑block ground, battery load‑test, corrosion guard on engine/mounts, and an in‑shop test run.
How long does a 100 ‑ hour service take?
Turnaround depends on your model, findings during inspection, and parts availability. We’ll provide a timeline estimate after intake. For the most accurate schedule, please call (916) 737-2628.
Do you service v ‑ drive and transmission components?
Yes. This package includes changing transmission fluid and checking V‑drive fluid levels, adding oil as needed, and inspecting for leaks. We also verify alignment and mounts.
Can I combine other repairs?
Often, yes. Many owners add minor electrical work, propeller service, or control adjustments during the same visit. For larger projects or repower planning, see Engine Installation & Repower.
Does this service maintain warranty coverage?
Following your manufacturer’s maintenance schedule and keeping documentation helps maintain warranty eligibility. ASFB Marine also performs warranty repairs in‑house for supported brands. Always review your specific warranty terms.