VAPOUR LOCK??
Hey all,
Right I'm literally engine illiterate! I know nothing about boat engines or any other type of engine infact so sorry for my poorly written post.
The engine is a self oil injection 2 stroke outboard engine. The engine runs sound when on flush muffs in the yard in idle and when in high revs. I've had a marine engineer look at it quickly before this and he found no obvious problems. The engineer advised to mix my own oil with the petrol at 50:1 incase the self oil mixer didn't work as it's an old engine. So I did and on my first outing found the engine was smoking thick blue smoke and cutting out and wouldn’t start again (easily). I then realized that the self oil mixer was working and that too much oil was being injected to the engine, hence the thick blue smoke. I then got rid of the self mixed petrol/oil and filled the tank with pure petrol. I took it out yesterday and the engine started 1st time, sounded good, no more thick smoke and launched out the marina nicely at 5-10knotts. When I accelerated and got to a decent speed (20ish knots - as a speed boat should), after 30 seconds of maintaining that speed a tapping noise (LIKE metal tapping metal) sounded, another 30 seconds later the engine would cut out. but if I put the engine back in neutral then it would stay running (most of the time) but would not accelerate at even 8th of the speed it should and then would cut out. Once it cut out it would start after a few goes. If I maintained a speed of 5-10 knotts throughout my outings, the engine was fine. I was drift fishing, therefore was starting and stopping the engine a lot. The engine after driving it slow (where I turned it off myself) was starting by the button 1st time every time.
A speed boat is no good without the speed, can someone please help?!
Additional Info – After the first outing mentioned above the engine wouldn’t start again. I had my suspicions about the fuel line as the pump wasn’t going solid when I pumped it. This then got the engine running again BUT I STILL have the problem with the engine cutting out at high speeds.
Someone told me to change the spark plugs and try a compression test. It had fresh plugs and a compression test just before I bought it. Compression test came back perfect.
I have been told it’s a possible vapor (air) lock and to tighten my jubilee clips – which I’ve done and still have the problem.
If it is an air lock how do I cool the system down to prevent this happening again??
If not air lock any other ideas
Many thanks
Hey all,
Right I'm literally engine illiterate! I know nothing about boat engines or any other type of engine infact so sorry for my poorly written post.
The engine is a self oil injection 2 stroke outboard engine. The engine runs sound when on flush muffs in the yard in idle and when in high revs. I've had a marine engineer look at it quickly before this and he found no obvious problems. The engineer advised to mix my own oil with the petrol at 50:1 incase the self oil mixer didn't work as it's an old engine. So I did and on my first outing found the engine was smoking thick blue smoke and cutting out and wouldn’t start again (easily). I then realized that the self oil mixer was working and that too much oil was being injected to the engine, hence the thick blue smoke. I then got rid of the self mixed petrol/oil and filled the tank with pure petrol. I took it out yesterday and the engine started 1st time, sounded good, no more thick smoke and launched out the marina nicely at 5-10knotts. When I accelerated and got to a decent speed (20ish knots - as a speed boat should), after 30 seconds of maintaining that speed a tapping noise (LIKE metal tapping metal) sounded, another 30 seconds later the engine would cut out. but if I put the engine back in neutral then it would stay running (most of the time) but would not accelerate at even 8th of the speed it should and then would cut out. Once it cut out it would start after a few goes. If I maintained a speed of 5-10 knotts throughout my outings, the engine was fine. I was drift fishing, therefore was starting and stopping the engine a lot. The engine after driving it slow (where I turned it off myself) was starting by the button 1st time every time.
A speed boat is no good without the speed, can someone please help?!
Additional Info – After the first outing mentioned above the engine wouldn’t start again. I had my suspicions about the fuel line as the pump wasn’t going solid when I pumped it. This then got the engine running again BUT I STILL have the problem with the engine cutting out at high speeds.
Someone told me to change the spark plugs and try a compression test. It had fresh plugs and a compression test just before I bought it. Compression test came back perfect.
I have been told it’s a possible vapor (air) lock and to tighten my jubilee clips – which I’ve done and still have the problem.
If it is an air lock how do I cool the system down to prevent this happening again??
If not air lock any other ideas
Many thanks
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