Date: 30-04-24  Time: 09:14 am

Author Topic: Not firing on cylinder 3  (Read 417 times)

basher

  • CBT Wobbler
  • *
  • Posts: 29
    • Main bike:
      FZS600 98-99
    • View Profile
Not firing on cylinder 3
« on: 18 October 2023, 07:07:28 pm »
Alright I've a lot to talk about here as I've tried a lot of things so far.


basically after i got the engine back together i did the old spraying water on the headers to see what was happening. at that stage only 2 cylinders were firing. after taking the carbs out and completely rebuilding them now its working on 1-2-4 but 3 is cold. i put a brand new plug in cylinder 3 and moved the plug wire from 2 to 3 basically swapping them, didnt make a difference. when i did take them all out to check for spark they all have blue spark. I did notice a little bit of plug cap arcing from cylinder 4 cap but thats attached to a different coil and 1-4 are fine so even though its not ideal i dont think its the issue.
THE ISSUE HAS ALSO MOVED FROM 2ND BEING COLD TO NOW 3RD BEING COLD, so it has swapped a cylinder somehow after I cleaned the carbs


so my symptoms are as follows.


in first and second gear around 4k RPM I can hear the 3rd cylinder waking up and firing it kinda stutters as it begins to get fuel to the cylinder then firing perfectly on all 4 cylinders from that rpm onwards.


below 3k RPM taking off feels lumpy like an old steam train firing up  :rollin


tiny drop of fuel now and then out of the 2nd carb bank overflow




----


now I did try a really rudimentary vacuum guage to sync the carbs but since then i did a bench sync and it feels way better, in high rpm it pulls very well. but maybe the 3rd cylinder is just miles off the rest. can carb sync issues cause a cylinder to not fire at all on idle?


---


if anyone has ever had a similar issue or knows what could be happening id like to hear your opinions as running on 3 is better than 2 on idle circuit but id like to be using all cylinders  :'( 

i just want a list of things to try and hopefully i can get it back to being fully operational  ;)
« Last Edit: 18 October 2023, 07:10:03 pm by basher »