Re: Valve rework and startup of 2004 Yamaha F90
Thanks so much for the feed back guys, I will try to answer all your concerns.
First to Silvertip. I tried to comprehend the manual instructions on the carburetor floats, but was not sure the floats were off from specs. My thought was, if the float had not been banged around, why would they need adjusting from factory settings. But that may have been a major error on my part. I am still researching the timing specs to understand how much, how far, and when. I wonder if the 13 deg is at idle and as acceleration is increased that number changes as the rpms increase, relative to computer input. Which brings me to the TPS, Which I will check once I understand the specifications. But I am finding out that the TPS is critical to a smooth engine. OK Robert Graham, To condense the story, the boat had been in storage at the Lake for app 1 1/2 years. Brought it home to get some use out of it. Cleaned as well as I though practical. At first crank it backfired once and then nothing. At closer inspection, I removed the flywheel cover and found that Dirt Dobbers had nested on the intake cam gear which threw the cam out of time, resulting in the bent intake valves. There was only slight damage to the pistons as you could see where the valves hit the piston, but I could not find any piston damage other than that. 99yam40, I do have a manual I purchased online. My RPM instrument is not working, but it idles very smooth and I am guessing at 800 Rs. Robert, I am reluctant to report suspect data, but to let you know what I know, using substandard equipment, I was able to record 120 psi on compression, so if there is piston damage other than what the eye could see, what would it be? All of the pistons come all the way up nearly flush or at flush with the block face.