...thing already, can't figure it out!? Hi,
My bike (vespa et2 50 cc carb version) has been riding like a dream since I purchased it, but the last couple of months in the rainy weather conditions here in London it has been more and more difficult to start on the electrical start, and finally also on the kickstart. A few days ago it wouldn't start. After some kicking on the starter and trying to start it electrically with jump leads it still wouldn't fire. I took out the spark plug and it was heavily carbonated and black. I cleaned it with my keys and gloves, stuck it back in the the engine and it started (just). Since I have switched off the engine, it hasn't restarted since. Also, the last couple of weeks the engine cut out immediately after stopping.
Now I have done the following:
- I fitted a new spark plug (BR9ES, NGK)
- Fitted a new malossi res sponge air filter cleaned the airbox
- Fitted a new little fuel filter
It still won't start, and subsequently I have checked:
- the spark, seems to spark a reasonaly good blue spark
- spark timing: the timing seems alright as well as I check whether it sparked when the cilinder was near it's highest point (although you can't measure this accurately, It never had misfired or late/early combustion when running either)
So it can not really be a spark-related problem.
Subsequently, I checked compression. I don't have a gauge, but while kickstarting the thing I held my finger in the spark plug hole and I can't realistically keep it on the without the air blowing out.. Furthermore, the bike is a commuter bike that does 30 miles a day, every day, and the last time I drove it home it did 40 mph as normal, so I can't imagine it's compression (the bike has 8900 miles on the clock).
Lastly (as it still didn't start), I took off the carburetor and cleaned it. It didn't look dirty at all. The float seemed in perfect condition, as was the float needle and the jets. Also the choke looked fine ( I don't have a multimeter, so I can't check).
Anybody has an idea where to look now? Today I tried to kickstart and hold my hand in front of the exhaust to seem whether I would feel the air "pulsing" out. No pulsing there, but that may be due to the fact that by kickstarting not enough pressure has built up in the engine. Can the exhaust be blocked?
Finally, the bike does not leak. If I take out the spark plug and kick on the kickstarter a couple of times, petrol squirts out, so there is not an absence of fuel, i can only think of it running far too rich to start.
As it still didn't work, I took a petrol sample directly from the hose that goes into the carburetor and it flowed freely. The petrol seems to smell right ad was highly inflammable, and is only a week old ( and all the fiddling with the fuel hose has caused at least a liter to flow through the engine)
It still doesn't start. I dipped the spark plug in the petrol, screwed it in and kickstarted, no result, even not 1 single combustion..
So now I'm a bit lost.. When I pulled the old plug from the engine it was blackish and fouled, so the engine must have been running too rich. I I try to start it now and after a few kicks I take out the spark plug, there's a fuel damp on the plug.
Please advise.
Regards,
Sebastian.
My bike (vespa et2 50 cc carb version) has been riding like a dream since I purchased it, but the last couple of months in the rainy weather conditions here in London it has been more and more difficult to start on the electrical start, and finally also on the kickstart. A few days ago it wouldn't start. After some kicking on the starter and trying to start it electrically with jump leads it still wouldn't fire. I took out the spark plug and it was heavily carbonated and black. I cleaned it with my keys and gloves, stuck it back in the the engine and it started (just). Since I have switched off the engine, it hasn't restarted since. Also, the last couple of weeks the engine cut out immediately after stopping.
Now I have done the following:
- I fitted a new spark plug (BR9ES, NGK)
- Fitted a new malossi res sponge air filter cleaned the airbox
- Fitted a new little fuel filter
It still won't start, and subsequently I have checked:
- the spark, seems to spark a reasonaly good blue spark
- spark timing: the timing seems alright as well as I check whether it sparked when the cilinder was near it's highest point (although you can't measure this accurately, It never had misfired or late/early combustion when running either)
So it can not really be a spark-related problem.
Subsequently, I checked compression. I don't have a gauge, but while kickstarting the thing I held my finger in the spark plug hole and I can't realistically keep it on the without the air blowing out.. Furthermore, the bike is a commuter bike that does 30 miles a day, every day, and the last time I drove it home it did 40 mph as normal, so I can't imagine it's compression (the bike has 8900 miles on the clock).
Lastly (as it still didn't start), I took off the carburetor and cleaned it. It didn't look dirty at all. The float seemed in perfect condition, as was the float needle and the jets. Also the choke looked fine ( I don't have a multimeter, so I can't check).
Anybody has an idea where to look now? Today I tried to kickstart and hold my hand in front of the exhaust to seem whether I would feel the air "pulsing" out. No pulsing there, but that may be due to the fact that by kickstarting not enough pressure has built up in the engine. Can the exhaust be blocked?
Finally, the bike does not leak. If I take out the spark plug and kick on the kickstarter a couple of times, petrol squirts out, so there is not an absence of fuel, i can only think of it running far too rich to start.
As it still didn't work, I took a petrol sample directly from the hose that goes into the carburetor and it flowed freely. The petrol seems to smell right ad was highly inflammable, and is only a week old ( and all the fiddling with the fuel hose has caused at least a liter to flow through the engine)
It still doesn't start. I dipped the spark plug in the petrol, screwed it in and kickstarted, no result, even not 1 single combustion..
So now I'm a bit lost.. When I pulled the old plug from the engine it was blackish and fouled, so the engine must have been running too rich. I I try to start it now and after a few kicks I take out the spark plug, there's a fuel damp on the plug.
Please advise.
Regards,
Sebastian.