Running problems

[fruitbat]

Hi folks am new to this forum but what I've read so far it great in here 😊 just bought a 1990 gsx600f
Great bike love it ! But not without its problemsI ran her for a fortnight without a problem then things started, I had an overflowing fuel problem which filled the sump and came out through air box but after after reading comments in this forum I quickly fixed this problem with a full carb clean and an oil change, all was great then 5 miles into the 2nd test drive she started going sluggish then stopped I got her started again and limped her home, cleaned the carbs again thinking I had missed somthing rebuilt her cleaned the plugs an sprayed everything with wd40 and then out for another test, again 5 miles in cut out wouldn't restart pushed her so about 1/2 a mile homewards then she started drover her home but sluggish and wouldn't tick over now the question could Un
Sinc carbs be the problem, when it's running giving it a we bit throttle it sounds rough not smooth like it did then it cuts out?? Any ideas? ?

[shpielers]

Did you replace the float needles and or set the float height during your work? Sounds like the engine is flooding, smell the crankcase oil and see if it smells of fuel.

[fruitbat]

Thanks for replying, I never changed anything or adjusted the float levels just cleaned out the build up of gunk, this week am going to strip her down again an check all measurements thanks again for replying.5

[Kreylyn]

I'd also check the petcock, fuel line(s), fuel filter, vacuum line to petcock situation to ensure sufficient fuel is flowing to the carbs.

Your bike should have 2 fuel lines (not vacuum hose used or that will collapse on you when hot), and a petcock screen but no inline fuel filters.

Test your petcock. I've posted enough times how to do that, and it's simple.

Krey

[fruitbat]

Thanks Krey, I've ordered a new petcock as the metal bit in side is bent and not pointing the right way, I did have in line fuel filters fitted but I've removed them, after I get the new petcock an measure the float heights I will build her back up and see how she runs
Thanks for the reply ☺

[fruitbat]

I removed the carbs again took them a part then rebuilt them following 1 of the threads on here making sure all the heights and measurements were correct I've been out on a test run tonight an she ran great tommorrow a second run, I'd that's successful I will get her plastics back on, thanks for everyone's comments and help 😊

[fruitbat]

The saga continues - after 2 successful test rides I now have fuel coming out the air box again this time I quickly got the air filler out to see what was going on - No 1 cylinder was full of fuel it's flowing up out where the needle goes in, I know the carbs are spotless I've cleaned them inside an out 3 times, I know I need a new petcock as the fuel is constantly on, but wouldn't the fuel stop going into the float bowel when they were full anyway and why only No1 the other 3 cylinders are dry ?? Please help desperate to get out riding 😕

[Kreylyn]

The saga continues - after 2 successful test rides I now have fuel coming out the air box again this time I quickly got the air filler out to see what was going on - No 1 cylinder was full of fuel it's flowing up out where the needle goes in, I know the carbs are spotless I've cleaned them inside an out 3 times, I know I need a new petcock as the fuel is constantly on, but wouldn't the fuel stop going into the float bowel when they were full anyway and why only No1 the other 3 cylinders are dry ?? Please help desperate to get out riding 😕

The float needle is not sealing, and it allowing fuel to continue to flow past.

Probably may need to replace that needle.

Next time you pull the carbs, clean them again. Check the float heights are correct. Then before putting them back on the bike, test them.

You can use water ( as long as you remove the float bowls again afterwards and fully dry them out) to test the float needles are sealing properly. Do this by using a tank to fill them through the fuel lines, and once full... blow on the fuel line. If you can move air or hear bubbles at all, the needle is not sealing. Fix it till it passes the test.

Krey