81 GSX1100E Breakdown??

[chickenstrip]

I decided to take my gsx to work today and about 5 minutes in it just started missing and running rough and then died altogether.I managed to get it started and limped home on 2-3 cylinders.When I pulled the plugs they are fowled and black.This bike has done only 33000ks original and is in mint condition and is only used maybe twice a month but has been tuned and serviced fanatically and never missed a beat?The valve clearances,carb balance and plugs where done 2 weeks ago and it was running perfectly over a 200k ride the day before?I fitted new plugs and it started and idled for a minute or so and then the same thing fowled plugs.Checked the airbox and its clean no fuel and the spark is strong.Any suggestions would be appreciated.

[SqDancerLynn1]

Maybe some water in the fuel or just some crap in the float bowls. Which pipes get hot when you start it ???

[chickenstrip]

Maybe some water in the fuel or just some crap in the float bowls. Which pipes get hot when you start it ???

Won't run at all now,I will have to have a serious look tonight it is sooty black stuff on the plugs not oil residue so it is getting way too much fuel or not enough air.I thought I knew these things pretty well but obviously not.My first thought was a cracked float or crap in a needle and seat but not all four at once?

[BassCliff]

Hi,

A couple more thoughts....Did you check the charging system? What's your voltage at the coils?


Thank you for your indulgence,

BassCliff

[chickenstrip]

Hi,

A couple more thoughts....Did you check the charging system? What's your voltage at the coils?


Thank you for your indulgence,

BassCliff

Charging is 13.75volts @idle or was 2 weeks ago new battery 6 months ago but will need to check the coils.I think it may be something electrical. maybe coils are breaking down under load.

[chef1366]

If it ran fine and overnight it started fouling plugs it should be ignition related.
See coil mod if it is the issue.
If you have a manual check the igniter and coils.

[chickenstrip]

Crankcase full of fuel !

When I removed the tank last night to check things out the fuel tap would not stop flowing fuel I had to stand the tank up to stop it leaking.When I checked the oil level it was above the window even with the bike on the sidestand.I drained the oil and sure enough there was about 2 litres of petrol in it.
I drained the oil filter cavity and let the whole thing drain for 2 hours filled it with fresh oil and hooked up a fuel supply and bingo bike runs perfectly again.I reconnected the tank just for a test ride and took it for a half hour ride and all seems fine no strange noises no exhaust smoke runs as normal.
I will buy a new fuel tap today and change the oil and filter again after a couple of hours more running.
I am hoping this has not caused any engine damage but the bike sounds fine at the moment.

[BassCliff]

Hi,

Wow. I guess it doesn't hurt to check everything over when you're troubleshooting. Good catch. I wouldn't think that there's any permanent damage. And now you have a nice clean crankcase!


Thank you for your indulgence,

BassCliff

[chickenstrip]

Hi,

Wow. I guess it doesn't hurt to check everything over when you're troubleshooting. Good catch. I wouldn't think that there's any permanent damage. And now you have a nice clean crankcase!


Thank you for your indulgence,

BassCliff

Still not sure why fuel ended up there instead of the airbox or out the carb overflow? If fuel tap was not leaking I would have been looking elsewhere as i have never heard of this causing plug fowling problems

Thanks for suggestions everyone

[TheCafeKid]

Still not sure why fuel ended up there instead of the airbox or out the carb overflow? If fuel tap was not leaking I would have been looking elsewhere as i have never heard of this causing plug fowling problems

Thanks for suggestions everyone

There are no overflows on the CV carbs.. they just fill up and drain out the throats into the airbox and crankcase. Change the oil, and filter, replace the petcock, and in about 50 or so miles change the oil and filter again. Gas on the rings and bearings is BAD BAD stuff, it will wash em down of oil and potentially ruin them.

[Mysuzyq]

My first thought on reading your original post was that you had maybe neglected to take the petcock off the 'Prime' position after starting it following a long period of inactivity....they sometimes run rough in that position, and could lead to all the gas-contamination, and fouling issues you later described, esp. if the carbs also need attention. If the petcock flows constantly even in the 'Run' position (absent any vacuum), it's probably time for a new one, before going over the carbs. Check that the petcock isn't leaking due to being left on Prime first though.
Tony.

[chickenstrip]

Have fitted the new fuel tap but decided to pull the carbs off and have a look.Found a lot of crap in the float bowl of no 1 carb and the needle had a bit of crap embedded in the little rubber tip. These are the after market ones off ebay and I think I might put suzuki needles and seats in again at some stage.The rest are spotless and I now have an inline filter.I changed the oil and filter again even though the old stuff was still very clean.No smell of fuel but guess this would burn off pretty quick anyway.Bike sounds as it alway has and running great.Hope it stays this way.

[chef1366]

Make sure the fuel filter is a 5/16" gravity fed type.

[chickenstrip]

I did not check the fuel filter but it's identical to the one on my GS1100G?

[chickenstrip]

Well I did not get away with this after all as the bike has started to burn oil
and a friend said there is a puff of blue smoke when changing gears I am hoping some new rings and a hone will be all thats needed but will post some pics of damage when I strip it down and find the money required.Very unhappy as this bike has never been apart.