Yamaha marine jet (1.8L HO, twin)
Yamaha's automotive-derived 1.8L (and TR-1) jet engines are reliable and cheap to maintain. The wear point is the jet pump — wear ring and impeller clearance degrade with hours and especially with sand/shallow-water running.
Service and what to check
Inspect wear ring and impeller for clearance/nicks; check cleanout-tube seals and reverse-bucket cables. Flush after saltwater use without fail.
Watch usage: above roughly 100 hours/year, this family starts losing reliability points — always weigh total hours against the boat's age, and on any outboard or I/O over a few years old, insist on a compression or leak-down test before money moves.
Boats that ship with this engine
Looking at a boat with this engine?
The engine is the single biggest reliability and value variable on a used boat. Paste the listing and BoatVerdict scores the engine risk for the exact hours and year you're looking at — plus fair value, red flags, and what to inspect.
Paste a listing, get the verdict →