location of Thermostat 2001 F80

[BayBouy01]

Can't find shop manual or diagrams on line anyone know where the thermostat is on the outboard?
Thanks

[almetelo]

Remove the flywheel cover and you'll find it.

Have a look on attachment.

Good luck

[boscoe99]

I would look at the top of the cylinder head.

2001 F80TLRZ Yamaha Outboard CYLINDER CRANKCASE 2 Diagram and Parts

[BayBouy01]

Thanks

You guys are fast!
I spent all day surfing the WEB and had just about given up.
My engine started "making oil" Gas in oil and I called a tech and he said one of 2 things; pin hole in fule pump diaphram &/or thermostat.
I pulled the fule pumps off and did a visual and replaced the back diaphram on each.
When I found the thermostat (thanks to you guys) it was baked, totally frozen open and I had to pull hard with a set of vise grips to get it off.
I'll pick up a new thermostat tomorrow, change the oil and filter and get it out for a good run and see it that was it.

is there a way to test a fuel pump for leaks on the bench?

[BayBouy01]

Thermostat was the problem

Put in new thermostat and oil and it rus like a top!
Nice warm water out the pisser almost immediately. Ran it in the yard on muffs for a while then took it out for an hour run at various RPM, about 20 min at lowest possible. Home checked oil - all is good.
I had this engine serviced in April when I bought the boat; compression, anodes, oil, lower unit oil, plugs, tune-up...
On my invoice they say "checked the thermostat OK" based on how bad it was I don't think they did a visual.
Luckily there appears to be no damage to the engine.
Thanks again.

[almetelo]

My thermostat had the same problem but fortunately didn't notice any problem.
When I was on my local dealer to buy a new one he said that is not really necessary because our waters are "worm at least in this season of the year" +/- 22șC so I saved that money but I not sure I did the right thing. So far just have low pressure on water peeing.
If on my 2 stroke outboard I was not worry about this but on 4 stroke I guess is better have the thermostat.

[almetelo]

Have a look on attachment.
I hope this can help.

Good luck!