2 replies to this topic

[mnewell]

Just bought a used 2007 150 Speedster 155hp. After boating a few hours running at high rpms I was unable to to throttle back below 6000. Quite disconcerting but fortunately out in open water and used the kill switch. moved the throttle back to idle position while shutoff then hit the start switch and away we go again at high rpms. Again hit the kill switch, after several iterations I decided to look at the throttle body on the engine. it appears that the cam would stick in a high fuel flow position, even when i moved the throttle control back towards idle it would only roll back a small amount. I searched on this forum and found the same issue on a 200 speedster but that problem was in the throttle control and not on the cam. i was able to rotate the cam manually until it would snap back to the idle position. I also found that moving the throttle control lever to full foward then snapping it back to idle a few times would help "unstick" the cam. the problem continued to occur numerous times, when i would go to a higher rpm setting the cam seemed to get stuck at the higher setting as i increased throttle. hoping this is not an expensive fix. any help would be appreciated.

[Kevin Leclair]

Have you checked your throttle cables?

[mnewell]

Have you checked your throttle cables?

yes. they appear to work fine. when i move the throttle lever i can see the cable moving the cam. the rigging for the cables appears to be fine and installed correctly. the reason i suspect the cam sticking is that it happens after the engine has been running for a while and heated up. i don't know if the warmer engine makes a difference or just manipulating the throttle creates the problem. since the previous owner had used it infrequently i just thought it was lack of use and considered lubricating the cam but i don't want to make it worse. i have a maintenance manual and operator manual on order to try some other troubleshooting but it is very frustrating to have this problem with a low time machine. as i said before i can "fix" it temporarily by snapping the throttle lever forward and aft several times or grabbing the cam on the throttle body and rotating it around the spring and letting it snap back to the idle position. but once i get going again the same thing happens. local dealer says it will take a couple of weeks to even take a look and i hate to miss two weeks off the water but i need to get it fixed. any other suggestions are welcome.