big cough

[tattoo]

i was going to post this earlier but wanted to check things first.....

coming back from squires the storm gave a big cough,ejected 2 very large flames out of the cans then layed a black smokescreen...i pulled the clutch in and listened for any knocking or rattling but heared nothing strange while coasting along so nursed it home steady.....after checking every hoses for splits/cracks,checked the timing,cct's,airfilter( K&N cleaned 2 days ago),plugs (which are new) and oil level... i started it again and raised the rpm upto 8000 both slowly and snapping it open and nothing...no smoke or flames,no knocking,slapping or rattling...infact it sounded fine...

the cough is just the storm,the flames should be an airleak somewhere on the pipes and although it's seems to of cleared now,the smoke is a mystery....anyone got any ideas please

[benny hedges]

you probably just loosened up a load of carbon in the headers with the big backfire.
next time you have the airbox off it might be worth checking if the oil catch tub is clear and the cam cover breathers are not blocked - it might've dumped a bit of oil in the airbox?
if you are using a k&n, did you use the blanking pieces that go over the breather ports in the airbox?

[tattoo]

do you mean the 2 rubber triangle caps?...if so,yes they're fitted...i did find a light misting of oil in the airbox so off it came and cleaned it out...the catch tub is clean,so are the breather pipes...the headers are now sat at my uncles with boiling costic soda inside them to clearout any carbon deposits and a spare set is fitted....just got to take it for a gentle run now...hopefully it'll behave itself.

thanks benny

[tony.mon]

Sounds more like a loose ignition connector somewhere.
Just pull apart and clean all of the connectors, from the ECU and igniter boxes through to LT side as far as plugs.
Because the exhaust pipes are linked it will always blow any smoke from either cylinder out of both, so it's not easy to find out which cyl caused this.

Lastly, if it does it again, kill the engine and pull out the plugs if poss- one should be dirty and show you what's going on.

Actually, clean the plugs anyway.

[AMCQ46]

Gesundheit

or is that for a sneeze?

[Flatline]

Sneezes

[tattoo]

tony....i checked all the connectors first becoz i'd had the subframe off lastweek for painting and they were all cleaned before rebuilding..

took it for a run to scarbrough this afternoon and it ran great,no coughs,bangs or splutters even when riding hard with a mate on a zx10...might sound odd but the engine feels looser,more revy,more responsive now...i don't know whats changed but i like it...i like it alot

[benny hedges]

Actually, clean the plugs anyway.

unless theyre iridiums.... in which case dont clean them, just replace them.
the coating doesnt like being cleaned.
tbh theyre past their best after 5-8k miles.

[tattoo]

yes they're iridiums and tbh i don't clean any plug,just replace them every 5k reguardless of the make.

[tony.mon]

Gesundheit

or is that for a sneeze?

According to Haynes specs, the gesund height should be 14mm, + or - 0.02

Not to be sniffed at.

Drop it round and I'll give you a hand (ker) chief.

Does it make a sort of "Fer" sound, before the cough?

It might be trying to tell you something.......

[AMCQ46]

I like the "fer" gag

[tattoo]

i like the "fer" gag too tony