Yamaha 30 hp lose of third cylinder

Birdup

Seaman Apprentice
Joined
Dec 28, 2003
Messages
45
THis is all on a 1986 30hp Yamaha oil injected 30ELJ<br />Here is what happened. I was out on a windy day and the boat ran fine and planed out all day. Then when I went to head back, against the wind, it would not plane out because the wind was pushing the boat and the bimini top way up causing the motor to run WOT but not on plane. It ran this way for about 20 min then I was able to turn sideways against the wind and get up on plane. After about 5 min on plane it had a power lose and the heat light temp/idiot light came on and it ran really rough. I idled it to the shore and took a look. The oil level was a little low but it was a long way from out. The fuel tank had about 1 gal left in a 6 gal tank. I pulled the plugs and the bottom cyclinder had a wet plug. I figured the plug was fowled from lugging the engine. I cleaned the plug and it got up on plane fine for about 30 seconds then it did the same thing. I idled it back to the dock and brought it home. It ran smooth at low rmps. The motor was borrowed so I need to fix whatever is wrong before I return it. So do you think it is a fowled plug? What should I check. I have a lot of OB experience just non with Yamahas. <br /><br />P.S. I'm buying a 89 30hp so any help here will help me in the future.
 

Birdup

Seaman Apprentice
Joined
Dec 28, 2003
Messages
45
Re: Yamaha 30 hp lose of third cylinder

Wow no help yet?<br /><br />Well I'm replacing the fuel pump assembly as well as all the hoses and new plugs. It is a 87 30hp SH
 

skidplate

Cadet
Joined
Feb 26, 2005
Messages
23
Re: Yamaha 30 hp lose of third cylinder

replace all plugs w/ new ngk and try again . This is a cheap fix
 
Top