wynjim55
Regular Contributor
Today I took my boat to the main public boat ramp nearby to test if it would run or even idle, should have stayed in bed. The outboard is a 1975-78 Mariner 55hp (Japanese built Yamaha copy 2 cyl 2 carbs).
On the trailer the outboard fired up and idled like a champion. After letting it warm up I put it in gear and everything ran as it should, idled and picked up revs as the throttle was opened. I selected neutral and let it idle for a minute before selecting reverse. Again everything ran as it should and picked up revs as the throttle was opened. Expecting the work I had done recently had paid dividends I decided to take it for a run. Reversed away from the trailer with no issues, selected reverse and it even idled, selected forward and we started to move towards the pontoon where I was going to tie up while me son got in.
The engine stalled and I drifted into place at the pontoon. From there it refused to start, even operating the throttle a little while my boy operated the starter wouldn't get it to play. Once it tried to hold idle but as soon as I tried opening the throttle, to help it keep ticking over, it gasped and stalled. We tried to get it to start with all the usual things, choke on, choke off, no throttle, part throttle, full throttle, jiggle the throttle, all to no avail. We eventually ran the battery down until it wouldn't turn over fast enough to keep persevering. With our tails between our legs we dragged the boat from the pontoon to the ramp and loaded it back on the trailer and returned home.
Having just dunked it in saltwater ordinarily I would give the motor a flush but when it won't even start you have a problem. In the driveway, and after the battery had time to recover a little I connected the water hose, pumped up the primer bulb and got my boy to kick it over just for giggles. By now I was looking for some humour. It fired into life and idled as it had a few days earlier in the driveway. I couldn't believe it, it idled until I disconnected the fuel line at the outboard connection and ran out of fuel.
The second last time this boat was in the water it struggled to start or idle, would only idle for less than a minute if at all, but if you got it started and quickly got under way, at wide open throttle it ran like a train. Every restart was the same.
The last time this boat was in the water, after finding a pin hole in the fuel line between the fuel pump and tee piece under a hose clamp, and replacing the gaskets between the air intake/carbs/spacer plates/reed blocks/block after checking the carbs for obvious problems, I managed to get it to idle by winding in the idle screw for the throttle plates. In the water it idled but erratically and would stall out without warning. Again, when under way it ran well.
Because of the problems encountered on recent previous outings I performed the following work within the last week:
rechecked all fuel lines and connections from tank to carbs and removed the water separating filter I fitted when I first got the boat - the filter was replaced before the last few outings
synchronised the two carburetor throttle and choke plates, which I didn't do last time I worked on things
set the idle circuit screws as in the manual.
All I can come up with given my lack of experience is:
i) My boat and outboard are allergic to salt water
ii)My boat and outboard suffer from separation anxiety when removed from the trailer.
If anyone has any suggestions I am all ears. Is this poor old girl ready for a complete rebuild or the scrap heap, or is there something I have overlooked. I need a coffee, if I start on anything else I may not stop.
On the trailer the outboard fired up and idled like a champion. After letting it warm up I put it in gear and everything ran as it should, idled and picked up revs as the throttle was opened. I selected neutral and let it idle for a minute before selecting reverse. Again everything ran as it should and picked up revs as the throttle was opened. Expecting the work I had done recently had paid dividends I decided to take it for a run. Reversed away from the trailer with no issues, selected reverse and it even idled, selected forward and we started to move towards the pontoon where I was going to tie up while me son got in.
The engine stalled and I drifted into place at the pontoon. From there it refused to start, even operating the throttle a little while my boy operated the starter wouldn't get it to play. Once it tried to hold idle but as soon as I tried opening the throttle, to help it keep ticking over, it gasped and stalled. We tried to get it to start with all the usual things, choke on, choke off, no throttle, part throttle, full throttle, jiggle the throttle, all to no avail. We eventually ran the battery down until it wouldn't turn over fast enough to keep persevering. With our tails between our legs we dragged the boat from the pontoon to the ramp and loaded it back on the trailer and returned home.
Having just dunked it in saltwater ordinarily I would give the motor a flush but when it won't even start you have a problem. In the driveway, and after the battery had time to recover a little I connected the water hose, pumped up the primer bulb and got my boy to kick it over just for giggles. By now I was looking for some humour. It fired into life and idled as it had a few days earlier in the driveway. I couldn't believe it, it idled until I disconnected the fuel line at the outboard connection and ran out of fuel.
The second last time this boat was in the water it struggled to start or idle, would only idle for less than a minute if at all, but if you got it started and quickly got under way, at wide open throttle it ran like a train. Every restart was the same.
The last time this boat was in the water, after finding a pin hole in the fuel line between the fuel pump and tee piece under a hose clamp, and replacing the gaskets between the air intake/carbs/spacer plates/reed blocks/block after checking the carbs for obvious problems, I managed to get it to idle by winding in the idle screw for the throttle plates. In the water it idled but erratically and would stall out without warning. Again, when under way it ran well.
Because of the problems encountered on recent previous outings I performed the following work within the last week:
rechecked all fuel lines and connections from tank to carbs and removed the water separating filter I fitted when I first got the boat - the filter was replaced before the last few outings
synchronised the two carburetor throttle and choke plates, which I didn't do last time I worked on things
set the idle circuit screws as in the manual.
All I can come up with given my lack of experience is:
i) My boat and outboard are allergic to salt water
ii)My boat and outboard suffer from separation anxiety when removed from the trailer.
If anyone has any suggestions I am all ears. Is this poor old girl ready for a complete rebuild or the scrap heap, or is there something I have overlooked. I need a coffee, if I start on anything else I may not stop.
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