Ok just bought a 1991 Grady white with twin 2003 Yamaha four stroke the engines ran well but one was idled up at 1200 rpm so being the not so smart guy I am I tried to fix it myself. So I took the timing cover off looking for a set screw to adjust the idle. Saw one at the very top of the carburetors on the right side of the engine (if you are standing behind the engine) under a sensor. Thinking this was the idle I turned it counter clockwise until rpm was at 700. But now I have a skip and a back fire when I increases throttle or try to run it between idle and 2000 rpm. After that it runs fine. So I turned the screw clock wise until the idle was back to 1200 but I still have skip.
Have I damage something?
If so what will it cost to repair?
Or is it simple and I can repair?
I’ve got twin 2002 F225’s and had the same issue you’re having. Turns out it was due to heavy corrosion on the throttle bodies. Chris and his team at Charleston Marine will take good care of you and has the equipment to properly clean and service the throttle bodies if that is indeed the issue.
Ok this is wierd.I have the same motors. I put my boat in the water today and my starboard motor went strait to 4500 rpms after I fired it up. What would cause this?
28 WA Hydra Sport
Twin 225 4 stoke Yammies
“Fin Loco”
Ok this is wierd.I have the same motors. I put my boat in the water today and my starboard motor went strait to 4500 rpms after I fired it up. What would cause this?
28 WA Hydra Sport
Twin 225 4 stoke Yammies
“Fin Loco”
Check that the throttle body plates are closing all way. Mine would stick open and cause it to hold idle around 1250-2500 rpms. Without pulling off the intake to inspect it visually, you can check the following to see if further diagnosis is required.
Pull of the top cover (3 X 10mm bolts) and remove the nuts (2 X 8mm nuts) from the throttle linkage rods that connect the to the top of the throttle bodies. Try to operate the throttle linkage by hand. If there is any resistance at all or if they are hard to open and close, there’s your problem. You still should remove the intake as it is just a few more nuts and bolts and you will be able to see directly inside the throttle bodies and confirm if they are closing all the way. I removed all throttle bodies and brought them over to Charleston Marine. They have an ultra sonic parts washer. Let them run a few cycles and you will be good to go - if in fact that is your problem.
Yamaha had two campaigns on a similar situation both of which pertain to throttle linkage bushings.
Campaign # - 02004-010 / Replacment Part # 90891-40590-00
Campaign # - 02003-019 / Replacemnt Part # 90891-40455-00
I fought mine all last summer and finally pulled it all apart to repair it. I didn’t install the campaign parts because my issue was corrosion on the throttle bodies. The port motor started doing the exact same thing toward the end of the season so I’m up for pulling it down here in the next few weeks. However, I’m considering installing the campaign parts this go round because of the low cost
reel free
very unlikely that you permanently damaged anything
the motor needs to be plugged in to the computer to see what its actually doing, then based on you moving the synchronizing screws, its going to need vacuum gauges hooked up and the butterflies re-synchronized.
reel excitement
only thing that can cause that to happen, is to much air going to the motor.
key is to find out where the extra air is coming from
Chris, after I fired the motor up and reved that high rpm’s I pushed in the button on the side and pushed throttle up and back to neutral, and she came back to 1000 rpms. I put it in gear and ran it, then it would not come out of gear until I shut the motor off.
28 WA Hydra Sport
Twin 225 4 stoke Yammies
“Fin Loco”
it wont shift because the rpms are to high
something is letting in to much air
throttle plates sticking open
idle air control failing
throttle cable sticking
etc.
you shut off the motor, and it takes the load off the clutch dog, and it will shift fine.
if you are at 1000 rpms and shift into gear you are going to kill your lower unit, very quickly
NOTHING WRONG WITH MY KEY BOARD
OUR BUSINESS MANAGEMENT SOFTWARE USES ALL CAPS
ITS WHAT I USE 90% OF THE TIME, AND I DONT REMEMBER TO UNCAP LOCK EVERYTHING