'89 35 hp mercury OB

[ritzlimo]

I have this engine on my pontoon boat. It has an automatic oil injector. The problem I keep having is that the river is shallow, so I run at idle speeds most of the time. The motor uses L76V plugs which is a bad design for a boat motor since they constantly foul out. (I believe it is a racing plug)I have had the mixture checked and it is correct.<br /><br />The bigger problem is, like clockwork whenever I switch tanks, within 5 minutes the engine dies out and will not stay running. The problem is always fouled plugs.<br /><br />Needless to say, it has taken all the fun out of this boat with the constant fear of it quitting. I always go up river, in case it breaks down I can work my way home via the current.<br /><br />Any suggetions?

 

[Laddies]

Re: '89 35 hp mercury OB

Get rid of that junk auto blend before it ruins your engine, your lucky usally the don't pump enough ouil and cook the engine. If you take the time to mix your fuel it will run much better--Bob

 

[ritzlimo]

Re: '89 35 hp mercury OB

I have been told that before. I think I will go ahead and do that. What is the correct mixture for the motor? I use 5 gallon tanks. Also, I have always used premium gas, does it matter?

 

[andy6374]

Re: '89 35 hp mercury OB

I think using 93 runs the engine too hard. I use 89. You will want to use a 50:1 mixture, that is add ~ 13 ounces of oil to your 5 galllon tank.

 

[ritzlimo]

Re: '89 35 hp mercury OB

Thanks! Will eliminating the autoblend solve my problem when switching tanks? My thought is for a short period it sucks pure oil before the new tank starts to mix. Do I just unplug the power contector from the unit and then bypass it with the fuel line?