tohatsu 9.9 problem child

[bodyman36]

help.. have had this thing in the shop for on and off five months,, it statrs with one pull idles fine and smooth , will run it the test tank great but when you put it on the boat in the atter after you get above half throttle it bogs down like it either starving or getting to much fuel anyone have same problem? need it to go fishing soon and seems the shop cant figure this one out

 

[Bear]

Re: tohatsu 9.9 problem child

What happens if you squeeze the bulb during this air or fuel starvation?<br />Did you ever try with the cowling off? Leaking powerhead gasket? Probably not... For how long did you test it in the test tank? How old is your enginge?<br />If it appears at about the same rpm every time my guess it is a clogged jet or the timing advance link adjustment. If you can get over this rpms for a few seconds it might be a stuck float valve.<br /><br />You don't give that much info. <br />Tell us more (in the same post please) and someone will get you some good answers.<br /><br />/Bear

 

[domingo]

Re: tohatsu 9.9 problem child

I had a similar problem with my Honda 9.9. Based on excellent suggestions made by members of this forum, I discovered the problem to be a bad spark plug. You find this by running the engine under load (in gear) and pulling one spark plug cable off at a time. If there is no noticeable change in engine performance, there is an electrical problem. Replace the spark plug to see if that fixes it...