[FONT="]Hi![/FONT]
[FONT="]I have this 1990 130HP Yamaha 2 strokes 130ETXD.[/FONT]
[FONT="]Symptoms:[/FONT]
[FONT="]Idle set at 750rpm, gives me 600/650 when in gear (smooth idle). I advance the throttle slowly and between 800 to 1000/1100 rpm the motor shakes enough to shake the whole boat. Passed 1200rpm, runs great. Cold or hot no difference.[/FONT]
[FONT="]
[/FONT]
[FONT="]What I have done so far:[/FONT]
[FONT="]
[/FONT]
[FONT="]1- Removed carbs, cleaned with ultrasonic and set floats at 16mm as per manual. and idle mixture screw set at 7/8 out.[/FONT]
[FONT="]2- Inspected the reeds while carb out, they appeared to be fine.[/FONT]
[FONT="]3- Set the ignition timing as per manual, rods at 53mm and 60 mm. 4 deg ATDC alined the mark on flywheel with trigger mark. set WOT timing at 22 deg BTDC and align mark as well.[/FONT]
[FONT="]Once timing set statically, verified with timing light and it gave me 5 deg ATDC at idle (manual says it should be at 5 deg, so all good there) [/FONT]
[FONT="]4- With carbs mounted, checked the sync and no adjustment needed there. No play either[/FONT]
[FONT="]5- Idle speed screw removed, set the throttle roller to throttle cam as per manual.[/FONT]
[FONT="]6- Started motor and adjusted Idle rpm to 750 in neutral.[/FONT]
[FONT="]
[/FONT]
[FONT="]7- Fuel pump replaced, not that the old one was bad but that is part of my preventive mx.[/FONT]
[FONT="]8 Checked compression, 125psi on all 4, it has been like this for the past 3 years, no changes there.[/FONT]
[FONT="]9- Did a decarb with seafoam and replaced spark plugs. [/FONT]
[FONT="]
[/FONT]
[FONT="]So this is where I am and still giving me some shaking between 800 and 1000 rpm.[/FONT]
[FONT="]
[/FONT]
[FONT="]
[/FONT]
[FONT="]There is 2 things that I found out while performing the work:[/FONT]
[FONT="]
[/FONT]
[FONT="]1- The throttle roller has a flat spot[/FONT]
[FONT="]2- After adjusting the timing as per manual, I am a bit dumfounded. After setting the roller with idle screw off, once idle speed adjusted to 750rpm, the roller isn't touching the cam any longer. Then of course when I had throttle, the timing arm advances before the roller touches the cam and adding fuel to motor. I don't get it... I read and re-read the manual to make sure that I understood how to set roller and timing. So why setting timing at 4 deg ATDC if when you advance throttle the timing advances before fuel is added???? [/FONT]
[FONT="]
[/FONT]
[FONT="]Would this explain the shaking? [/FONT]
[FONT="]
[/FONT]
[FONT="]I would say that the space between roller and cam at idle is about 1.5 mm and that it takes about 7 deg of timing advance before the roller contact the throttle cam. Seems like a lot of advance ??? [/FONT]
[FONT="]
[/FONT]
[FONT="]
[/FONT]
[FONT="]
[/FONT]
[FONT="]
[/FONT]
[FONT="]Anyway, this is where I am and I am in desperate need for help and ideas...[/FONT]
[FONT="]
[/FONT]
[FONT="]Thank you.[/FONT]
[FONT="]
[/FONT]
[FONT="]Frederic[/FONT]
[FONT="]
[/FONT]
[FONT="]
[/FONT]
[FONT="]I have this 1990 130HP Yamaha 2 strokes 130ETXD.[/FONT]
[FONT="]Symptoms:[/FONT]
[FONT="]Idle set at 750rpm, gives me 600/650 when in gear (smooth idle). I advance the throttle slowly and between 800 to 1000/1100 rpm the motor shakes enough to shake the whole boat. Passed 1200rpm, runs great. Cold or hot no difference.[/FONT]
[FONT="]
[/FONT]
[FONT="]What I have done so far:[/FONT]
[FONT="]
[/FONT]
[FONT="]1- Removed carbs, cleaned with ultrasonic and set floats at 16mm as per manual. and idle mixture screw set at 7/8 out.[/FONT]
[FONT="]2- Inspected the reeds while carb out, they appeared to be fine.[/FONT]
[FONT="]3- Set the ignition timing as per manual, rods at 53mm and 60 mm. 4 deg ATDC alined the mark on flywheel with trigger mark. set WOT timing at 22 deg BTDC and align mark as well.[/FONT]
[FONT="]Once timing set statically, verified with timing light and it gave me 5 deg ATDC at idle (manual says it should be at 5 deg, so all good there) [/FONT]
[FONT="]4- With carbs mounted, checked the sync and no adjustment needed there. No play either[/FONT]
[FONT="]5- Idle speed screw removed, set the throttle roller to throttle cam as per manual.[/FONT]
[FONT="]6- Started motor and adjusted Idle rpm to 750 in neutral.[/FONT]
[FONT="]
[/FONT]
[FONT="]7- Fuel pump replaced, not that the old one was bad but that is part of my preventive mx.[/FONT]
[FONT="]8 Checked compression, 125psi on all 4, it has been like this for the past 3 years, no changes there.[/FONT]
[FONT="]9- Did a decarb with seafoam and replaced spark plugs. [/FONT]
[FONT="]
[/FONT]
[FONT="]So this is where I am and still giving me some shaking between 800 and 1000 rpm.[/FONT]
[FONT="]
[/FONT]
[FONT="]
[/FONT]
[FONT="]There is 2 things that I found out while performing the work:[/FONT]
[FONT="]
[/FONT]
[FONT="]1- The throttle roller has a flat spot[/FONT]
[FONT="]2- After adjusting the timing as per manual, I am a bit dumfounded. After setting the roller with idle screw off, once idle speed adjusted to 750rpm, the roller isn't touching the cam any longer. Then of course when I had throttle, the timing arm advances before the roller touches the cam and adding fuel to motor. I don't get it... I read and re-read the manual to make sure that I understood how to set roller and timing. So why setting timing at 4 deg ATDC if when you advance throttle the timing advances before fuel is added???? [/FONT]
[FONT="]
[/FONT]
[FONT="]Would this explain the shaking? [/FONT]
[FONT="]
[/FONT]
[FONT="]I would say that the space between roller and cam at idle is about 1.5 mm and that it takes about 7 deg of timing advance before the roller contact the throttle cam. Seems like a lot of advance ??? [/FONT]
[FONT="]
[/FONT]
[FONT="]
[/FONT]
[FONT="]
[/FONT]
[FONT="]
[/FONT]
[FONT="]Anyway, this is where I am and I am in desperate need for help and ideas...[/FONT]
[FONT="]
[/FONT]
[FONT="]Thank you.[/FONT]
[FONT="]
[/FONT]
[FONT="]Frederic[/FONT]
[FONT="]
[/FONT]
[FONT="]
[/FONT]