The Marine Knowledge Network
Field write-ups from real jobs - what broke, what fixed it, torque specs and part numbers included. Ask it a question; specs answer inline.
30 articles for “testing”
Sterndrive Spring Recommissioning Checklist
... Sniff test after warm-up: raw fuel smell = shut down and find it. 4 ...
Outboard Compression Testing: How to Do It and Read the Results
## Why it's the first test on any used or sick engine A compression ...
Evinrude/Johnson Two-Stroke No-Spark Diagnosis
... 4. **Stator and timer base/trigger:** resistance and DVA-test per the service manual ...
Spring Recommissioning Checklist: Outboard Boats
... fuel "just to test" - Skipping the lanyard and bilge pump tests — the two cheapest ...
The On-Water Diagnosis Kit: What's Actually in the Bag
... This is the field-tested kit list. ## Diagnostics - Multimeter with DVA/peak-reading adapter ...
Transom Rot Assessment: Do This Before You Hang an Engine
... 2. **Tap test:** knuckle or a small plastic hammer across the transom in a ...
Outboard Overheating: A Diagnosis Flow That Doesn't Guess
... Pull the thermostat and test in hot water; check the service manual for the ...
Sea Trial Checklist for Mechanics
... rpm steady, alarms self-tested, charging voltage on the meter - Shift engagement F-N ...
Outboard Fuel Pump Diagnosis: Lift Pumps, VSTs, and Primer Bulbs
... 4. **Clear-hose test:** tee a short clear section before the engine and watch ...
Boat Trailer Lights and Wiring Troubleshooting
... 1. **Prove the tow vehicle first.** Test the vehicle-side connector with a 4 ...
Suzuki DF Lower Unit Oil Change and Water Intrusion Signs
... Quote a proper pressure test and possible reseal or gearcase exchange; do not just ...
Outboard Power Tilt/Trim Troubleshooting
... Swap the identical up/down relays as a quick test where applicable. 3. Test ...
Gelcoat Crack Repair: From Spider Cracks to Gouges
... Tap-test and moisture-check around any crack field. If the laminate sounds dull ...
Exhaust Manifold and Riser Inspection on Marine V8s
... Tap test and visual inside the passages; heavy scale flaking means the water jacket ...
Prop Selection Basics: Pitch, Diameter, and Hitting the RPM Window
... Run a WOT test: normal load, trimmed properly, GPS speed and tach reading. A ...
Pontoon Boat Inspection: Logs, Leaks, and Pre-Season Checks
... Soap-bubble testing with **low-pressure** air (a shop vac in blow mode is ...
Mercury Outboard Water Pump / Impeller Replacement
... Water-test on muffs before the lake test. Confirm a strong telltale within seconds ...
Yamaha WaveRunner No-Start Diagnosis
... load-test, not just volts. PWC batteries are small and die young; corroded terminals ...
Bilge Pump Setup Done Right
... pump killer found in the wild. ## Testing on every visit - Lift the float (or ...
Hydraulic vs Cable Steering: Diagnosis and Service
... Disconnect the cable at the engine and test each part separately: wheel spins free ...
Boat Trailer Bearing Service (and Bearing Buddy Myths)
... New cotter pin, cap on, spin test, and re-check hub temperature after the ...
MerCruiser Winterization (Raw-Water-Cooled)
... 7. **The drive:** drain and refill gear lube (milky = pressure test before spring), grease ...
Volvo Penta Sterndrive Annual Service Essentials
... the oil (milky = water intrusion — pressure test before it floats again; glitter chunks = internal ...
MerCruiser Raw Water Impeller: Alpha vs Bravo Differences
... the overheat later - Dry-running to "test" before the pump is primed ## When to ...
Trailer Surge Brakes: Inspection and Service
... Road test: brakes should apply smoothly under moderate braking, no grab, no pull, and ...
Quoting a Repower: The Mobile Mechanic's Guide
... than the discount - Skipping the water test and prop verification line — an unpropped repower ...
Marine Batteries and Wiring Basics
... Always **load-test**; resting voltage lies. A battery can read fine and still collapse ...
MerCruiser Alpha One Bellows Inspection: The Boat-Sinker Check
... floating (below-waterline leak). ## The listen test With the drive off or via the ...
Submerged PWC / Water Ingestion: The First 48 Hours Matter
... Do not crank it.** Not to test, not "just briefly." Water in a cylinder ...
Reading Marine Spark Plugs: A Diagnosis in Your Hand
... Any time plugs come out — tune-up, compression test, winterization — lay them out **in ...