montyburns
Cadet
- Joined
- Aug 8, 2007
- Messages
- 6
I have a '67 Evinrude 80 HP Speedifour on a 16' Crestliner. The prothat when I try to get the boat to plane, it will plane for about 5 seconds blem is and start running rough and then I lose the plane. When I checked the plugs, 3 are burning perfectly with 110 compression in each cylinder. The Number 4 cylinder shows a wet plug with 100 compression(Checked compression cold)I am getting a spark on this wire. I just changed and set the points and condenser as recommended. Same result. Fuel mixture is 50:1 . I am stumped! This is a V4 engine, why wouldn't another plug be wet also? Would this eliminate a carburator problem? The motor starts very easily and idles fine. I even reversed the low speed jets, no difference. My service manual says there are no High speed jet adjustments for this motor. My friend thinks it may be a loose reed valve. About a month ago, I had the boat going 25 mph for about 15 minutes at about half throttle. If I increased the throttle it began to hesitate. A loose reed valve? I doubt it. The engine also has blue silicone on the suspect side of the cylinder head( same side as cylinder 4). My neighbour figures this may be the problem. I spoke to the previous owner last night and asked him if he put the silicone on the motor. He said no,and the motor always responded well for him. I guess I should remove the head or is there something simple I'm overlooking? Thanks for any info, Monty
