HELP! Again...

[crumbobly]

Hey guys,

Well im back again with yet another problem with my bike (1992 Suzuki GSF250)
And the saga continues....

After giving my carbs a generous cleaning and tinkering around with float heights, mixture screws and the like. I got her runnning pretty bloody well especially at the top end

And seeing as i didnt really have much use for my bike at current time being off from uni i parked her up for maybe a few weeks (3-4?)

Anyway i had urges to go for a ride the other day so hopped on and off i went. Got about 2km down the road (running beautifully) and giving it a bit of a work out all of a sudden i loose power... feels and sounds like not running on a cylinder. Got progressivly worse. Then revs drop slowly and would only crawl along at idle with wide open throttle. Got off and noticed a whole heap of oily petrol type fluid all over my rear tyre and guards which had come from my air box. Didnt want to start..
Had to take it home in a van

Anyway at home after going over everything i noticed what i swear was a drop of water on #1 spark plug. So assuming maybe water in the tank/carbs i took them apart blew out all the lines and put in fresh fuel..

Still no luck. It will fire up, idle and rev fine for a while then run crap and start bogging down and will die and will only run at idle speeds if throttle held wide open.

I checked spark and put new plugs in as i had some id been meaning to install.
I noticed #2 exhaust was relativly cool compared to the rest.

Coolant level hasnt seemed to have changed.

I rechecked float heights and as i cant find a manual for it i went for 14mm as most were at that height and im sure i read it somwhere but from which float the big side or the little side????

Im really confused. What the hell could it be?????

If i can get my hands on a compression tester ill check it out but im really hoping its not that serious.

Im sorry its a fair amount of reading but i wanted to give as much info as possible.

Im begging anybody for suggestions.

HELP PLEASE.... uni starts next week and i hate driving in auckland traffic..

(also not sure if this is correct place to put the post but seing as i had played with the carbs i decided to start there first, i guess time will tell)

[Brian d marge]

all the other cylinder plug colors are ok ? just number 2 is a bit cool ? ie flooding?

Stephen

[crumbobly]

all the other cylinder plug colors are ok ? just number 2 is a bit cool ? ie flooding?

Stephen

Well thats my initial thought was that its getting too much fuel and flooding. The plugs looked pretty black and sooty before i replaced them, ill have to pull them again and have another look but as they brand new im not sure it will show much.

Also i lowered the neddle one clip notch on the carbs to try lean it out a bit.
Maybe ill change the mixtrue screw???

Strange though as it was running fine and then all of a sudden this problem..

[lone_slayer]

Make sure your getting spark to all cylinders mine recently had a nice clean then balance etc and an hour or so of riding it started acting like a right shit. took it in and found I was getting no spark on number 4 tried another coil a voila. So hopefully getting mine back today

Good luck

[crumbobly]

Make sure your getting spark to all cylinders mine recently had a nice clean then balance etc and an hour or so of riding it started acting like a right shit. took it in and found I was getting no spark on number 4 tried another coil a voila. So hopefully getting mine back today

Good luck

Yea i might give that a try, looks like someone who owned it before me might have had trouble with it as it has a different lead (from the other 3) siliconed into the coil. But i was getting spark on all 4 when i tested it..

[scumdog]

Yea i might give that a try, looks like someone who owned it before me might have had trouble with it as it has a different lead (from the other 3) siliconed into the coil. But i was getting spark on all 4 when i tested it..

Coils (your bike does have one/them?) can crap out when they are warm - yet work perfectly when they are cooler.

I know this from sad experience.

[Drew]

Coils (your bike does have one/them?) can crap out when they are warm - yet work perfectly when they are cooler.

I know this from sad experience.

The bandit runs two coils, each one for two cylinders. Wasted spark deal, so if the coil was crapping out I'd expect it to run on two rather than three.

One of the few engines I've blown up was one of those, and it presented in exactly the same manner as what you describe, loss of power and oil spewing out of the airbox. It can only be caused by a few things, and since your bike has a wet sump, it can then only mean it's getting massive pressure in the sump. I'd be compression testing before I bothered with anything else.

Sorry to be the bearer of bad news, I could be wrong though

[Brian d marge]

The bandit runs two coils, each one for two cylinders. Wasted spark deal, so if the coil was crapping out I'd expect it to run on two rather than three.

One of the few engines I've blown up was one of those, and it presented in exactly the same manner as what you describe, loss of power and oil spewing out of the airbox. It can only be caused by a few things, and since your bike has a wet sump, it can then only mean it's getting massive pressure in the sump. I'd be compression testing before I bothered with anything else.

Sorry to be the bearer of bad news, I could be wrong though

yes I was trying to keep it simple first
Check the basics first , now a notch here or a mm there on the settings wont make a hill of beens to the diagnosis so don't worry about that
Compression , its amazing how low it can be and still run , but if one is clearly lower than the others, do the oil in the plug hole thing to check for a stuck valve , if no chage its piston area
Coils As scumdog say Coils tend to break down when they get warm so get your missus hair dryer onto them get them nice and toasty you can swap coils over and if the problem moves or is in ONE cylinder .....you can see where I am going with this

logical , one step at a time starting with the basics

and for your sake I hope drew is wrong ,,,,,,,

Stephen

[Henk]

I'm a bit concerned with the oil spewing thing.
Check your oil level and if it way higher than you would expect given that it has just spat a whole load of it out, check to see that it isn't an oil - petrol mixture.
Have seen something similar on a bike that had sat for a fair while with maladjusted float levels and the fuel tap left on.
The high float levels caused most of the gas in the tank to flow down the inlet manifolds, past the rings and into the sump. This was on a GS650 so a 4 stroke.

[Drew]

Coils As scumdog say Coils tend to break down when they get warm so get your missus hair dryer onto them get them nice and toasty you can swap coils over and if the problem moves or is in ONE cylinder .....you can see where I am going with this

logical , one step at a time starting with the basics

and for your sake I hope drew is wrong ,,,,,,,

Stephen

Hope I'm wrong too, but running on three wont make oil start spewing out of the engine unless it's running on three for days on end, and it washes the bore so bad it looses compression. Either way I'm afraid, the result is the same.

[Brian d marge]

I'm a bit concerned with the oil spewing thing.
Check your oil level and if it way higher than you would expect given that it has just spat a whole load of it out, check to see that it isn't an oil - petrol mixture.
Have seen something similar on a bike that had sat for a fair while with maladjusted float levels and the fuel tap left on.
The high float levels caused most of the gas in the tank to flow down the inlet manifolds, past the rings and into the sump. This was on a GS650 so a 4 stroke.

Hope I'm wrong too, but running on three wont make oil start spewing out of the engine unless it's running on three for days on end, and it washes the bore so bad it looses compression. Either way I'm afraid, the result is the same.

Henks Idea is a good one and if the breather is into the airbox ,,,, I do agree though not looking good.

Stephen

If you drain a bit of oil , does it look like or feel/smell like it has gasoline mixed in it??

[crumbobly]

Ok cheers for the input guys much appreciated, im gona try a few of the suggestions tomorrow.

And yea the breather is into the air box.

If Drew does happen to be right, whats involved in rectifying it???
new piston and rings???
or something else???
or another engine???
or scrap the bike for parts and buy another???

I can do and are confident in doing all the labour myself. Its more or less cost of parts or availability im worried about.... bike only cost me $1500

[Max Preload]

I would suggest that if the bike is stored outside, and got rained on or you washed it, that the water made its way down the suppressor cap and shorted that cylinder out and only got onto the tip of the plug when you removed the plug from the cylinder. That is to say, the water is not from inside the the cylinder.

Also, when you did the carbs did you drain the fuel tank to remove water? If not, you might well be looking at the fuel being contaminated again.

[crumbobly]

If you drain a bit of oil , does it look like or feel/smell like it has gasoline mixed in it??

I just had a look and it seems to me that there is more fuel than oil in there haha.

So i think this is a good sign?

So ill just put in new oil, which it needed anyway, and sort out my floats... and maybe not leave it on prime.... if thats what i did

[Brian d marge]

I just had a look and it seems to me that there is more fuel than oil in there haha.

So i think this is a good sign?

So ill just put in new oil, which it needed anyway, and sort out my floats... and maybe not leave it on prime.... if thats what i did

shhhhhhh



Stephen