See full version: Yamaha f225 overheating when trimming up
I have to tilt my F225 before I can get it to pee while running on muffs. Others have said the same. Your domestic water pressure may not be high enough to prime the water pump. This would be my first guess as to why the housing is melting.
I'm sure you're aware of the F225 exhaust corrosion issue. It is possible that your exhaust components have corroded through allowing the cooling water to bypass the engine and go straight to the ehaust. Looking up the exhaust with the foot removed, do you see a black uneven surface with white marks or crystals? If so, corrosion may be your issue. Check this out F225 Corrosion Fact Check - The Hull Truth - Boating and Fishing Forum
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I was going to refer to the THT site the same. more
if i was again buying a F225 from manufactured date of late 2001 to 2004, i'd have the lower end pulled and inspected prior to sale.
IMO, its not if the F225 needs fixing, but WHEN. I'd factor in the repair cost into your buying consideration. [links]
I also called a GW dealer in the location of the boat I was looking at and they were not familiar with the F225 issues, the boat owner also mentioned not hearing about the issue and felt the F225 was in great shape and had never seen any problems over a 3 yr period
If you want to learn more about the issue, read this: more
seems like there may be a need for both sensors and switches to agree on some motors that the motor is over heating before alarm sounds. more
For the F150 , the numbers I've seen are: [links]
The cooling system is pretty basic and you've been thru most of it.
always post what motor you are talking about in the 1st of thread. more
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