Small outboard cuts out

I had a similar problem with my honda 2.2hp 4stroke. To cut a long story short that went along the lines of the posts in this thread, I finally admitted defeat and took it to a Honda dealer. He diagnosed "old" fuel. I was very skeptical. He asked me how old my fuel was and I admitted that the fuel in the can on the boat might well have been over a year old. I was told that "modern" unleaded contains a specified amount of ethanol (10%? IIRC) and this degrades and reduces its octane rating much more quickly than pure unleaded of the olden days. This makes the engine run really badly. I tipped out the fuel (into the Peugeot car..) and put fresh fuel in and it ran fine.

Maybe I have had the wool pulled over my eyes, but it worked for me - and only costs 5 litres of fresh fuel and a little time flushing out the old stuff, so might be worth a try?

P
 
I had a similar problem with my honda 2.2hp 4stroke. To cut a long story short that went along the lines of the posts in this thread, I finally admitted defeat and took it to a Honda dealer. He diagnosed "old" fuel. I was very skeptical. He asked me how old my fuel was and I admitted that the fuel in the can on the boat might well have been over a year old. I was told that "modern" unleaded contains a specified amount of ethanol (10%? IIRC) and this degrades and reduces its octane rating much more quickly than pure unleaded of the olden days. This makes the engine run really badly. I tipped out the fuel (into the Peugeot car..) and put fresh fuel in and it ran fine.

Maybe I have had the wool pulled over my eyes, but it worked for me - and only costs 5 litres of fresh fuel and a little time flushing out the old stuff, so might be worth a try?


P
Yes, that is a good point.
Cheap to try, as you say.
I've had one engine, a little generator that would not start on old fuel, but once it was going it was OK.
 
I had exactly the same problem in the same engine which was also lightly used. I put in a new plug and it worked for a while. Then the problem returned. One dealer failed to solve it but when I was in Dartmouth I tried another dealer and he diagnosed another faulty plug. One new plug later ( plus a spare) and its been working perfectly ever since. He said that these engines can be a bit hard on plugs but was surprised two had failed with little use.
 
He diagnosed "old" fuel. P

I use fresh fuel at the start of each season. When the problem first appeared I renewed the fuel and during my diagnosis have been using fresh fuel, so that that on this occassion.
 
Thanks for those who point to ignition system.

I remembered I had an old noen tester. Using this it is clear to see a much weaker light when the engine cuts out. Earthing the plug end then shows a bright light, so I think that points to plug rather anything else on the system. Off to buy a another plug this morning.

Ian
 
I have a set of 4 of those neon testers. They save hours of fiddling about by confirming the HT side of things, or not.
I just fixed my leaf blower, which wouldn't start. By using the tester I knew straight away that the HT was fine and it was the fuel side that was not working.
They are so much more positive than holding a plug against the head. And you're less likely to get a shock.
 
Last edited:
In a previous life I was an agricultural engineer. As such I spent many years working on single cylinder engines, mowers, chainsaws and the like. Failure of the coil at running temperature is uncommon but does happen. Insulation breakdown in the LT windings. Without a proper tester it is hard to diagnose but I have deffo come across it several times. No way you can substitute the coil for a known good 'un I suppose, just to check it.
 
I have a set of 4 of those neon testers. The save hours of fiddling about by confirming the HT side of things, or not.
I just fixed my leaf blower, which wouldn't start. By using the tester I knew straight away that the HT was fine and it was the fuel side that was not working.
They are so much more positive than holding a plug against the head. And you're less likely to get a shock.

When I was a youth, a friend of mine used his sister as a spark plug tester. He got her to hold the plug then operated the kick start on his Norton Dominator. When she screeched and leapt into the air he moved on to the fuel system.
 
I've had the same problem with my Suzuki 2.2. Tried all the usual things, cleaned fuel system, new plug, head off & water passages cleaned up and new gasket and still it stops after a few minutes but it usually starts again straight away. Gave up last summer and went back to the ancient Honda which started 2nd pull on old fuel and has not missed a beat since(the only reason I used the Suzuki was that it was lighter). Might have another go at it in when the weather gets warmer.
 
What kind of ignition system ?-if its a traditional magneto then both the coil and condenser can cause this type of problem.If its one of those solid state types then check out the pick up/coil because I have had several of these fail on chainsaws.
 
I've had the same problem with my Suzuki 2.2. Tried all the usual things, cleaned fuel system, new plug, head off & water passages cleaned up and new gasket and still it stops after a few minutes but it usually starts again straight away. Gave up last summer and went back to the ancient Honda which started 2nd pull on old fuel and has not missed a beat since(the only reason I used the Suzuki was that it was lighter). Might have another go at it in when the weather gets warmer.

Did you true the face of the head before fitting the new head gasket?
 
I've had the same problem with my Suzuki 2.2. Tried all the usual things, cleaned fuel system, new plug, head off & water passages cleaned up and new gasket and still it stops after a few minutes but it usually starts again straight away. Gave up last summer and went back to the ancient Honda which started 2nd pull on old fuel and has not missed a beat since(the only reason I used the Suzuki was that it was lighter). Might have another go at it in when the weather gets warmer.

Try yet another plug. I've no idea why the original one failed and why a new replacement only lasted a couple of trips. It was really strange how it started first pull and would run forever in the dustbin but failed after a minute or so when on the dinghy. Then it would restart after a couple of minutes only to fail again a minute later. These signs could also occur with a blocked breather in the fuel cap but I would expect the engine to run a long time before enough negative pressure built up in the fuel tank.
 
Off to buy a another plug this morning.

New plug seems to have done the trick. I can't make the engine die in the test tank (water butt), but I wont be confident until I have it on back of dinghy and run it for prolonged period.

Thanks for all the suggestions. I hope it's been worth it. If not, I will ebay the motor and buy a new one.

Ian
 
New plug seems to have done the trick. I can't make the engine die in the test tank (water butt), but I wont be confident until I have it on back of dinghy and run it for prolonged period.

Thanks for all the suggestions. I hope it's been worth it. If not, I will ebay the motor and buy a new one.

Ian

Thanks for the feed back. Hope its cured. Surprising how often a new plug seems to sort these small outboards out when the symptoms suggest something else.
 
New plug seems to have done the trick. I can't make the engine die in the test tank (water butt), but I wont be confident until I have it on back of dinghy and run it for prolonged period.

Thanks for all the suggestions. I hope it's been worth it. If not, I will ebay the motor and buy a new one.

Ian
That's good news. If it still works on the dinghy, buy another new plug as a spare. Sod's law will then ensure you never need it.
 

Other threads that may be of interest

Top