1975 Johnson 70

james2222

Cadet
Joined
Sep 5, 2008
Messages
6
Whats up guys. i have a 1975 Johnson 70. The motor runs great when it is out of the water. in gear.. out of gear.. whatever. when i put in in the water it starts out fine then 10 to 30 mins. later it starts bogging badly and will hardly start. Once out of the water it runs fine again. I pulled the plugs and one seemed to have oily water on it..?? any suggestions?
 

BKS72

Petty Officer 3rd Class
Joined
Sep 5, 2008
Messages
99
Re: 1975 Johnson 70

Have you checked the compression? Dunno a whole lot about them but if you're getting water on the plugs it could be a bad head gasket. Silly question, but when you run it out of the water are you putting muffs on it or just running it dry?
 
Top