spark plugs fouled after changing oil brand

basshunter62

Seaman Apprentice
Joined
Jan 4, 2010
Messages
34
1995 merc 90 hp 3 cil I went from useing quick silver 2 stroke oil to using west marine oil. I have oil injection. sence switching, eng fowels out spark plugs. this boat is new to me this year the prev. owner gave me some leftover quicksilver so its the ist time adding something outher then quick silver. both are sinthetic blends. could the viscosity be different from one to an outher.
thanks for any help
sorry about the spelling spell check not working
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: spark plugs fouled after changing oil brand

What ratio are you using? Is the West Marine oil rated TC-W3?
 

basshunter62

Seaman Apprentice
Joined
Jan 4, 2010
Messages
34
Re: spark plugs fouled after changing oil brand

ya oil is tcw3 as for the ratio im not shure over the winter i rebuilt the carbs and changed the o rings on the oil injection unit and ajutsed the linkage between carbs and injection pump by lining up marks at injection pump per service manual. i should note that thay may fowel after mabe 2 tanks of gas. you can feel it getting progressivly worse. this is a bass boat. I do a lot of short runs across the water and mostly use trolling motor when im out. hopefully this helps thanks for your input
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: spark plugs fouled after changing oil brand

I really doubt that changing from one TC-W3 oil to another is going to cause any trouble.

I would suspect that something in the servicing you did is causing your fouling.

Confirm that you are using the recommended plug and gap.
 

basshunter62

Seaman Apprentice
Joined
Jan 4, 2010
Messages
34
Re: spark plugs fouled after changing oil brand

I,m useing ngk plugs they dont look ajustable their a flat bottom plug ???
 
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