Home / For international owners / Claims
Jet ski rolled over: what happens to the engine?
Short answer
Rolling a jet ski over rarely damages anything by itself.
The expensive moment is the start attempt afterwards,
because water standing in a cylinder bends the connecting rod as soon as the engine turns.
A jet ski goes over on its side more readily than any other craft on the water. That is the design, not a mistake by the rider, and on a breezy day it happens to beginners and instructors alike. What matters is not the capsize but what follows it. Manufacturers specify the direction in which the machine must be rolled upright, usually on a label at the transom. Turn it the other way and water travels through the exhaust towards the engine, silently, with nothing visible from outside.
The real damage happens at the first press of the starter. Water cannot be compressed: if it is standing in a cylinder, the piston meets a column that will not give way. The result is called hydrolock, and it usually means a bent connecting rod, in bad cases an engine written off at the block. This is exactly where two separate questions part company in a claim. The capsize is an external event. The engine damage is a consequence of it, and the question asked is whether that consequence was unavoidable or whether it arrived with a start attempt after the roll. So it is worth reading the wording carefully before the season: whether consequential damage to machinery after an insured event is within the contract, how gross negligence is treated, and whether separate machinery cover exists at all.
When it happens, one short rule applies: do not start it. Roll the machine upright in the direction the manufacturer specifies, tow it in or recover it ashore, and have the plugs pulled and the water drained before the engine turns for the first time. That is workshop work, not ten minutes at the pontoon. Report the incident to your insurer even when nothing appears to be broken, and record where and how it happened. A machine handled correctly after a roll very often runs on as if it had never been over.
Worth remembering
Roll upright
in the direction the maker specifies
Start it
only after the workshop has seen it
The capsize seldom costs the engine. The start attempt afterwards does.
Questions
What owners ask us about this
Can I restart the jet ski straight after a capsize?
Better not. If water has reached a cylinder, the first start attempt destroys the engine, because water will not compress. Drain it first, and that job belongs in a workshop rather than at the slipway.
Which way do I roll it back upright?
The way the manufacturer specifies, normally shown on a label at the transom. Rolled the other way, water runs through the exhaust towards the engine without anything being visible from outside.
Is the engine damage after a roll a claim?
That depends entirely on the wording you hold. What gets examined is whether the engine damage follows from the insured event itself or arrived with the start attempt afterwards. Read the policy.
Should I report a capsize if nothing looks broken?
Report it. Water damage inside an engine often shows up only weeks later as rust or a change in running noise, and by then you need the recorded incident to show where it came from.
Related
Not sure whether you qualify?
Whether it is “Jet ski rolled over: what happens to the engine?” or another question: send us your residence and the flag your boat flies. You will get a straight answer in one email; including a no, if that is the answer.
Was this useful?
