2016 Yamaha 250 timing belt

[Cape Escape 209]

Newbie here with a question about timing belts: Just bought a 2009 Escape 209, repowered in 2016 w 250HP Yamaha 4 stroke with 290hrs. When I had it winterized the service guy recommended a new timing belt & tensioner. Yamaha recommends new belt at 1000hrs or 5 years. Do you guys rely on hours or years when replacing timing belts? IMO it seems really early to have that repair done but would like to hear from more experienced owners.
Thanks in advance...

 

[seasick]

The belts age even if not used so the years are important. If the motor is heavily used, it might accumulate 1000 hours in less than 5 years. In that case more frequent changes are recommended

 

[wspitler]

My 2007 F250s had 1100+ hours at 15 years and I inspected them visually for cracking or fraying every year. They still looked good when I sold the motors. That was 15 years in the Florida heat. The new owner didn’t change them, but I would have had I kept them.

 

[family affair]

A timing belt failure on an interference engine is catastrophic. That said how often do you hear of timing belt failures before 100k miles on poorly maintained cars? Almost never. To get 100k on a car you are looking at 7-10 years and 2k+ hours. The engine bay of a car is WAY hotter than a 4 stroke outboard cowling.
IMO timing belt replacements on Yamahas benefit the dealers way more than the customers. Kinda like annual gear oil, spark plug, and water pump changes.
If it were mine I'd give it a look a couple times a season. If it isn't cracking, dusting excessively, fraying, or the tensioner making noise, I'd run it till year 10 and then pony up.

 

[seasick]

A timing belt failure on an interference engine is catastrophic. That said how often do you hear of timing belt failures before 100k miles on poorly maintained cars? Almost never. To get 100k on a car you are looking at 7-10 years and 2k+ hours. The engine bay of a car is WAY hotter than a 4 stroke outboard cowling.
IMO timing belt replacements on Yamahas benefit the dealers way more than the customers. Kinda like annual gear oil, spark plug, and water pump changes.
If it were mine I'd give it a look a couple times a season. If it isn't cracking, dusting excessively, fraying, or the tensioner making noise, I'd run it till year 10 and then pony up.

Timing belt failures on cars with metal chain belts are pretty rare. Most failures are on belt driven models. I agree that the dealers and manufacturers recommend more frequent maintenance than is probably necessary. In nay case, the OP should at least have or do a thorough inspection of the belt and idler as suggested.
I am not sure but don't these motors require somewhat regular valve clearance adjustments?

 

[family affair]

I am not sure but don't these motors require somewhat regular valve clearance adjustments?

There is an interval for inspection, but I wouldn't say it is often. From what I have been able to gather, most 4 stroke outboards rarely have valves go out of spec over their lifespan.
For automotive applications the valve to cam clearance typically become loose and get noisy at idle. If they get tight, that's another story.

 

[seasick]

I did lookup the schedule and the valves should be inspected clearance should be adjusted at 5 yr or 1000 hours.
Here is the list of initial and routine maintenance items

Yamaha Four Stroke Maintenance Schedule – SIM Yamaha Blog

blog.simyamaha.com

This blog also references the need to inspect and service the timing belt on a regular basis since as has been pointed out, the motor is an interference design meaning that if the timing belt breaks or shifts enough, moving parts in the motor will collide with each other likely causing extensive damage.