Did you get any instructions from the previous owner? If it's a 4 stroke waverunner there will be a dipstick on the engine block, but I'm guessing it's probably a 2 stroke engine because most watercraft used 2 stroke motors clear through the 1990's. The oil will be mixed with the gasoline when you fill it, bottles of 2 stroke oil can be purchased at most stores that carry oil. Your waverunner can be mixed at 50:1, which equals out to be 2.6 oz of oil per gallon of gasoline. On a 2 stroke engine the engine gets lubrication from the oil mixed with fuel and will burn up fast if straight gasoline is used. Let me know if you have any troubles, but try to get ahold of the previous owner to get some more info.
Hi, Anonymous and the usual suspects are:
1. Severely discharged or a damaged battery should have 12.5 volts or more and be able to pass a proper "LOAD" test if necessary, you may have a preliminary reading of 12.5 volts or more but little or zero amperage the battery is faulty and must be replaced, AGM batteries fail in this scenario more so than lead-acid batteries.
2. Check battery terminals for damage or corrosion, check the battery cables at "BOTH" ends for loose, corroded, or broken connectors, "INSIDE" and outside the cable harness, perform connector wiggle test and check cables with an ohmmeter if necessary.
3. Faulty main circuit breaker and or connections.
4. Faulty ignition coil and or connections.
5. Faulty spark plug, oil or gas fouled, wrong heat range or service type, wrong gap, loose in the cylinder head, broken electrode or insulator.
6. Faulty spark plug cables, leaking or broken, internal damage check for spark leakage in the dark.
7. Faulty ignition module, switch, CKP, MAP, CMP, sensor and or any connector in the ignition circuit could have corroded, loose, or broken pins/sockets
8. Burnt exhaust valve or air leak in the exhaust system.
9. Improper valve clearance (too tight).
10. Check for generated diagnostic codes.
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