Re: Yamaha f225 high temp alarm, Help!
I have a 2002 yamaha f225 on my parker 2310. I have been having issues with the high temp alarm going off randomly for a couple of years now. It only happens when the motor is at low rpms 600-1000. I shut the motor off when the alarm sounds, it resets itself and is fine unless I continue to run the boat at a low rpm. I have changed the water pump multiple times, the housing, seals, impeller, etc. I just recently put new thermostats and a new poppit valve in as well and my high temp alarm went off again the other day while the motor was idling at 600 rpm's. Anyone have any ideas?
Thanks,
Lee
I hate to be the bearer of bad news but what I will bet you are experiencing are issues related to major exhaust gas corrosion issues in the midsection of your engine. The Yamaha F225s, especially the 2005 and older model years are notorious for this. This is a wide spread issue and an expensive one. The low speed over heat alarms are one of the first symptom that manifest the problem . The oil pan sits atop the mid section and the potential exits for it to be involved in the corrosion mess as well. Parts alone for the "fix" used to be over $2000 but Yamaha has lowered the price on the parts to around $1100 , including oil pan and new oil pump (there is also an issue with oil pump leaks on the F225s, so while the power head is off it makes sense to replace the oil pump. The parts are relatively cheap for the oil pump. Labor from a Yamaha Dealer is gonna be roughly a grand give or take. The Power Head has to come off to do the fix.
I just went through this entire process this Winter and it absolutely sucks. Lots of threads over on the Hull Truth with pictures , just Google "Yamaha F225 Exhaust Corrosion" and you will find PLENTY of information that you don't wanna know. Here is a thread to get you started
http://www.redregulator.com/forum/showthread.php?t=442.
If you have changed out your water pumps, then you know dropping the lower unit is no big deal. Drop the lower and shine a flash light up the leg. This is not gonna be a 100% spot on diagnosis but my money says you will see a LOT of pitting and corrosion on what you can see, a bore scope inspection will likely give you more things to see you wish you had not.
I hope all the above is wrong but I'd wager and give odds ,your engine has the Yamaha F225
ROT.
I have the parts that came off my engine , pretty shocking how badly corroded some of them were.
Unfortunately fresh water flushing after use has absolutely zero effect on preventing this mess.