1995 Johnson 150 hp fouled plug

Johnnykfish

Recruit
Joined
Sep 11, 2009
Messages
2
Motor was running rough. Pulled plugs. Top right plug was completely fouled with a tan crust. Not just a little crust but covered the entire electrode and gap. Replaced plug but have not left dock yet to see if this happens again. Plugs were new in spring. maybe 50 hrs. All other plugs wre normal. Any ideas? Thanks
 

boobie

Supreme Mariner
Joined
Nov 5, 2009
Messages
20,826
Re: 1995 Johnson 150 hp fouled plug

When you say top right plug are you looking from the back of the mtr? If you are that would be # 1 cyl. If it is, these mtrs were known to have water injestion in that cyl from a defective block. Run it again and see what happens. Don't laugh at this but if you're in a salt water area if it happens again take the plug out and lick it. If it tastes like salt you'll know what the the prob is. Been there and done that.
 

jwellcraft

Petty Officer 1st Class
Joined
Nov 5, 2009
Messages
233
Re: 1995 Johnson 150 hp fouled plug

Great answer boobie, and johnnykfish I think boobie is right because I just had to replace my block because of the same problem. There are compaines that can fix this but you will have to strip your motor down completly to bare block and have it repaired because it will have to be welded on the inside of the water jacket area and the #1 cylinder sleeve will have to be pulled and welded behind that as well. If it is in salt water I wouldn't wait too long because salt water intrusion gets on all of the internal parts and then rust starts very quick. Sorry but it's no joke..
 

Johnnykfish

Recruit
Joined
Sep 11, 2009
Messages
2
Re: 1995 Johnson 150 hp fouled plug

Thanks for the responses. Not exactly the easy fix I was looking for. It is in saltwater so I will be tasting this weekend. I will let you know. Thanks again
 
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