Overheating 1999 Yamaha 200 Hp Saltwater

[TerryDVM]

Motor has 120 hrs and flushed EVERYTIME I use. I took to a reputable outboard repair place here in Florida with overheating problem at cruise speed (3500 RPM). He replaced WP Impeller, Popit and other simple things. He water tested to find problem not solved. He discovered water squirting out from head at 5000 RPM, so I authorized removing heads to check for blocked passages. Heads corroded, so he sandblasted and reinstalled. Water tested again and found water in lower engine cowling. At first, he thought it came from improper head gasket installation - so he removed and replace gaskets again. Water test failed again at Hi RPM. Mechanic said he found water coming out from under power head at Hi RPM water test, so now says he needs to pull Power Head to replace gasket under P/H.
Has this been a common problem with this motor? Sound logical? The mechanic has done things for me and many of my neighbors and always seemed OK. My bill before pulling power head is at 1000.00 and another 500.00 + parts for pulling power head. Is this normal? I'm getting uneasy being this problem keeps going further on a motor that has low hours.

TerryDVM

 

[pine island fred]

Re: Overheating 1999 Yamaha 200 Hp Saltwater

Terry, is that a typo are did you mean 120 hr.? And it was flushed after each use. Was this a different power head installed for you and you only have 120 hrs. on it? Where did all that corrosion come from?
Check my post a few days back on YAMAHA OVERHEAT FIXED, just got lucky but I did rectify a hair pulling problem on a 91, 200 hp. Maby that will help. Do you operate it in saltwater? good luck FRED

 

[TerryDVM]

Re: Overheating 1999 Yamaha 200 Hp Saltwater

Fred, 120hr original PH/Motor. Always been used in salt water. Thanks for the info, I printed off your explanation and will discuss with my mechanic. Hopefully he finds the problem.
Thanks again - Terry

 

[rorypff]

Re: Overheating 1999 Yamaha 200 Hp Saltwater

120 hrs in 8 years and there is that type of corrosion - something horribly wrong here! Have you owned this motor since new, as if second hand then there is no ways one can believe that hour meter. Seriously with those problems then this motor has no anode protection and you're sure not flushing with salt water?

 

[TerryDVM]

Re: Overheating 1999 Yamaha 200 Hp Saltwater

rorypff: I purchased this Yamaha brand new on a 23 SeaPro. I've had the zinc changed when needed. The boat sits in salt water at my home, but the engine is completely out of water. Only thing I can think of is - that Yamaha's factory flushing system doesn't flush the block properly. I always run fresh water through the factory flush out hose for 15 minutes or more. I don't run the motor while flushing and water squirts out the pee hole and foot freely.
Thanks - Terry