Cap'n Morgan wrote:
Your engine/drive combo is usually not a worry, if it was older than a 1999 with OMC stuff, then it might be an issue.
Can't remember if 1999 still had the ill-fated VDO gauge cluster. Hopefully you do not.
I know that the 1999-2000 Horizons had the VDO gauge cluster, so the Vista probably did as well. Mine is still working fine, but many owners have had problems. There is one company that does repairs. You can also find threads on how to add a ground wire to the VDO board that fixes some problems. There are other threads on how to change out to conventional gauges.
The Volvo Penta drive and 5.7 is a great unit, but I/O's do take more maintenance than Outboards. Not knowing your experience with I/O's, I will mention the following which is well covered in this forum:
Waterpump impeller should be changed often (I would say 3 years max, but 1-2 years is better). If you wait until the vanes break off, they clog up the thermostat housing or other passageways.
Outdrive Gear Oil level/color should be checked (every 2-3 months?). Milky oil means water intrusion, so the seals would need repair. Change Outdrive Gear Oil every 1-2 years (Volvo Synthetic Oil).
Outdrive should be removed Once per year, Grease Splines and Universal Joints, Check Bellows and replace if questionable (especially upper bellows, because a leak there = water in the boat and ruined universal joints). Exhaust bellows (lower one) does not matter much because a leak there does not matter...most have drain holes anyway.
Exhaust Manifolds / Risers must be replaced before they rust through and leak water back into the engine. 5-12 years depending on Salt vs Fresh water and how they were cared for. Many threads cover this issue.
Some VP Fuel Injected engines had an issue with the Electric Fuel Pump, but I think it was later years than yours.
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"Knot Easy" 2000 Horizon 240 Volvo 5.7GS /SX
tow: 2017 Honda PILOT EXL-AWD
prev. boats:
'87 Chaparral 198CXL 4.3 OMC Cobra
'69 Jetstar 16ft Ski Boat, 115hp Yamaha
'68 Aluminum Jon Boat, 3hp Sears
'64 Water Wings