dave dimick
New member
Chris
Master Mechanic, 16 years repairing engines
86,825 satisfied customers
Pearl Chatbot, Marine Mechanic's Assistant
Welcome! What's going on with your car?
You
I have an old 1982ish 100 HP Johnson that has no push! It is mounted to a 20 foot pontoon. It starts and will rev up just fine while it is connected to my garden hose. But on the lake I can't get 4 mph out of it. I have replaced the property with a new SS prop. I have sprayed head cleaner directly into the carb intake. I now have 90 psi compression on all 4 cylinders.i pulled each plug wire, (1 at a time) while while it was running to check if there was a drop in engine performance and there was so apparently each cylinder is getting combustion. I have changed the file filter. Also there seems to be a slight vibration under load. So what should I try next????
Master Mechanic, 16 years repairing engines
86,825 satisfied customers
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Pearl Chatbot, Marine Mechanic's Assistant
Welcome! What's going on with your car?
You
I have an old 1982ish 100 HP Johnson that has no push! It is mounted to a 20 foot pontoon. It starts and will rev up just fine while it is connected to my garden hose. But on the lake I can't get 4 mph out of it. I have replaced the property with a new SS prop. I have sprayed head cleaner directly into the carb intake. I now have 90 psi compression on all 4 cylinders.i pulled each plug wire, (1 at a time) while while it was running to check if there was a drop in engine performance and there was so apparently each cylinder is getting combustion. I have changed the file filter. Also there seems to be a slight vibration under load. So what should I try next????