Tweet
Hi - New to the forum here. Let me start out by saying that I'm fairly new to working on outboards but I do consider myself fairly mechanically inclined.
I was given a 1989 40ESF a couple of years ago that wasn't running and figured it would be a good motor to fix up as a project. Long story short I rebuilt the carbs, replaced the water pump, put in new plugs and I've enjoyed the motor for two years now - it has been very reliable.
With that said there has been one problem that I can't seem to figure out: After the boat has been sitting up for a few weeks, clean unburnt oil will leak out and will continue to slowly leak until the entire oil reservoir is empty. If the motor is tilted up the oil pools in the plastic air silencer (leaks through the bottom carb), If tilted down in the running position the oil leaks out of the prop. If I pull the spark plug for the bottom cylinder it is full of oil.
So now before each trip (if the boat has been sitting up) I have to pull the bottom plug and crank the engine with a heavy rag behind it and blow all the oil out otherwise my starter can't even turn the thing over due to the amount of oil in the cylinder
. Once that is done the boat performs great (of course pretty smoky at first) and seems to consume oil at what I'm guessing is a normal rate.
The only real troubleshooting I've done was to replace all three check valves on the oil lines. This did not fix the problem. I also checked the linkage that actuates the oil pump and it seems to be adjusted correctly. Not sure where to go from here.
Should I drop the $200 on a new oil pump?
Also - and this is where I'm feeling like a novice - I saw in the schematic that there are some reed valves behind the carbs. If these are functioning properly shouldn't they keep the cylinder from filling with oil? I might be misunderstanding the role/operation of these things though.
Oh and I know I can just disable the pump and pre-mix but I would really like to have this thing work as designed. All of my internet research has turned up how incredibly reliable the precision blend system is. I feel like I should be able to fix this.
Sorry for the long first post but I wanted to put as much info in there as possible.
Any help is appreciated!
I was given a 1989 40ESF a couple of years ago that wasn't running and figured it would be a good motor to fix up as a project. Long story short I rebuilt the carbs, replaced the water pump, put in new plugs and I've enjoyed the motor for two years now - it has been very reliable.
With that said there has been one problem that I can't seem to figure out: After the boat has been sitting up for a few weeks, clean unburnt oil will leak out and will continue to slowly leak until the entire oil reservoir is empty. If the motor is tilted up the oil pools in the plastic air silencer (leaks through the bottom carb), If tilted down in the running position the oil leaks out of the prop. If I pull the spark plug for the bottom cylinder it is full of oil.
So now before each trip (if the boat has been sitting up) I have to pull the bottom plug and crank the engine with a heavy rag behind it and blow all the oil out otherwise my starter can't even turn the thing over due to the amount of oil in the cylinder
. Once that is done the boat performs great (of course pretty smoky at first) and seems to consume oil at what I'm guessing is a normal rate. The only real troubleshooting I've done was to replace all three check valves on the oil lines. This did not fix the problem. I also checked the linkage that actuates the oil pump and it seems to be adjusted correctly. Not sure where to go from here.
Should I drop the $200 on a new oil pump?
Also - and this is where I'm feeling like a novice - I saw in the schematic that there are some reed valves behind the carbs. If these are functioning properly shouldn't they keep the cylinder from filling with oil? I might be misunderstanding the role/operation of these things though.
Oh and I know I can just disable the pump and pre-mix but I would really like to have this thing work as designed. All of my internet research has turned up how incredibly reliable the precision blend system is. I feel like I should be able to fix this.
Sorry for the long first post but I wanted to put as much info in there as possible.
Any help is appreciated!
Comment