Hi folks, very nice to join you all as a new member. I ride a lovely ST1100 ABS/TCS, 2000. Having recently put Diesel into her I have encountered a new issue as I've been trying to clear the diesel out. There is oil - not much - in the air filter and she is putting out plumes of smoke from both of the exhausts. There is a weak smell of oil in this smoke. The bike could be running 'fine' until I push along above 3600rpm and then after a while the smoke just bellows out BOTH exhausts. All four plugs foul up also. Before I go too deep into the carbs or valves is there a different solution? I suspect a blocked oil breather? Or, does the st1100 have a PCV valve? Thanks all, your thoughts would be hugely appreciated. Safe riding.
Oil In Air Filter
- Thread starter martin cullinan
- Start date
Slydynbye
Will ride for Pie
Welcome Martin
Overfilling oil is a common cause of oil in the air filter.
Oil should be at about mid line on the window while on the center stand.
Of course having put Diesel in can have many more effects. How did you clean the fuel system?
Overfilling oil is a common cause of oil in the air filter.
Oil should be at about mid line on the window while on the center stand.
Of course having put Diesel in can have many more effects. How did you clean the fuel system?
I want to welcome you to the forum from great the greatest STate on the WeST coast of USA. That would be Washington STate....
Now did you put Diesel into the tank and ran the engine? A very little oil in the air filter is normal and OK. There is a valve that take the gasses from the engine case and brings it onto the carburetor. How many miles are on the bike?
Now did you put Diesel into the tank and ran the engine? A very little oil in the air filter is normal and OK. There is a valve that take the gasses from the engine case and brings it onto the carburetor. How many miles are on the bike?
Thank you! I managed to pump out most of the diesel and then diluted it with petrol to try run it through. 80K miles and normally running great! Where is that valve? I would like to investigate it..... and Washington State sometime!!
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Thank you! Yes, I had too much oil in the bike (not wise, I agree) but the diesel issue has caused some sort of a knock-on problem. I had been riding the bike with new plugs to gradually clear out the remaining diesel but this side issue of big smoke above 3600rpm occured. I emptied out the fuel system, turned the motor without plugs to push through the clean fuel and started to investigate the carbs when I first spotted the oil. I'm hoping there might be another way of clearing up the smoke issue before taking things apart. I will investigate that breather valve also. Might you have any ideas?
- Joined
- Sep 5, 2018
- Messages
- 1,771
- Age
- 70
- Location
- Newlyn, Penzance, Cornwall, UK
- Bike
- 2000 ST1100Y
- STOC #
- 9006
Welcome to the forum from Cornwall UK! Glad you have managed to sort out your problem.
If it is the breather, then as far as I recall there are two pipes which come up from the bowels to the sub air filter at the front of the air filter. I'd take the filter housing off and check the pipes are clear and the sub filter is clean.
The sub filter may fall apart in your hands if it does then a sponge air filter off a lawnmower may be a good alternative.
Although it does seem strange that this only occurred once you filled it with diesel, thinking out loud, dangerous I know, could it be diesel residue in the exhaust?
Oil level to the top line wouldn't cause an issue, check the oil after the bike has been standing overnight. Some will disagree with this but it works for me.
Upt'North.
Edit......it might just clear it out if you held it at about 6000 rpm for a few minutes, any gear you like and preferably somewhere out of town, I would expect diesel smoke to burn white'ish.
The sub filter may fall apart in your hands if it does then a sponge air filter off a lawnmower may be a good alternative.
Although it does seem strange that this only occurred once you filled it with diesel, thinking out loud, dangerous I know, could it be diesel residue in the exhaust?
Oil level to the top line wouldn't cause an issue, check the oil after the bike has been standing overnight. Some will disagree with this but it works for me.
Upt'North.
Edit......it might just clear it out if you held it at about 6000 rpm for a few minutes, any gear you like and preferably somewhere out of town, I would expect diesel smoke to burn white'ish.
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I would change the plug the O2 sensors. Does the ST1100 have the equivalent of a catalytic converter or something in the exhaust for emissions? Does the smoke level go down when the bike is hot? Or is it there all the time above 3600 RPM?
How much of the diesel did you get out before putting gas in? Did you empty the tank below the seat?
You are always welcome in Washington STate.... The Western US and Canada mountains are fabloious from the Rockies to the Pacific Ocean.
Cheers,
Craig
How much of the diesel did you get out before putting gas in? Did you empty the tank below the seat?
You are always welcome in Washington STate.... The Western US and Canada mountains are fabloious from the Rockies to the Pacific Ocean.
Cheers,
Craig
No Cats were hurt in the making of ST1100's. No sensors in the pipes.
Upt'North.
Thank God. I'm glad to hear about the Cats.... I like cats but the Boss is deathly allergic to them...
Cheers,
Craig
Take the seat off, get a long piece of 5/16 fuel line. Remove the fuel line to the pump and attach the new hose on and let the other end go into a buck or gas can. With an external battery (or bikes battery) jump the fuel pump and completely drain the fuel tank. What little is left will not hurt anything. Fill with fresh gas and ride. While in there check fuel shut valve or just bypass it. Drain or replace the fuel filter. You need to be sure that 95 % of the diesel fuel is gone
Thanks Al, I’ve done that. Great trick jumping the fuel pump
I like cats, just not in bikes Once it starts it might or might not stop depending on the severity of the cause. I’m going to do a full and proper service on her as soon as the parts arrive and I’ll report back to you guys. It’s an interesting one!....
Slydynbye
Will ride for Pie
The Breather does not meet the sub air filter, the 2 hoses leaving either side of the sub air filter go to each pair of carbs, no other connections.
I am to assume there was to smoking problem till the diesel fuel went in. Then I would not worry about the oil in the air box some is normal. Diesel fuel should not damage anything. Run thru a tank of gas then reevaluate.
CYYJ
Michael
Hi Martin:
Welcome to our forum community!
As others have mentioned, a small amount of oil residue in the air filter enclosure (and on the filter itself) is normal, it's a result of vapours coming from the breather.
If the bike has ever tipped over to 90° or more with the engine running, a LOT of oil will go up the breather hose into the air filter.
Note the picture of my bike above my name on the left hand side (the avatar) - when my bike rolled upside down into the ditch, a lot of oil got into the air filter. When I started it up, it smoked like a destroyer under attack in a WW II movie. I then rode about 300 miles to the city limits of Zurich - no problems - until I hit a big bump in a construction zone on the expressway, which was sufficient to bounce all the loose oil on the bottom of the filter enclosure into the carbs. There was a big Mercedes S right on my tail, about 30 feet behind me, and he just disappeared in the cloud of smoke... when the smoke cloud cleared, I could see the Mercedes far, far behind me, the windshield wipers and washer going at full blast trying to clean the mess of his windshield... it is the funniest thing that has ever happened to me while riding the moto.
I bet he figured I had some kind of defensive smoke system installed - I also bet he has never tailgated a motorcycle again since that day.
Michael
Welcome to our forum community!
As others have mentioned, a small amount of oil residue in the air filter enclosure (and on the filter itself) is normal, it's a result of vapours coming from the breather.
If the bike has ever tipped over to 90° or more with the engine running, a LOT of oil will go up the breather hose into the air filter.
Note the picture of my bike above my name on the left hand side (the avatar) - when my bike rolled upside down into the ditch, a lot of oil got into the air filter. When I started it up, it smoked like a destroyer under attack in a WW II movie. I then rode about 300 miles to the city limits of Zurich - no problems - until I hit a big bump in a construction zone on the expressway, which was sufficient to bounce all the loose oil on the bottom of the filter enclosure into the carbs. There was a big Mercedes S right on my tail, about 30 feet behind me, and he just disappeared in the cloud of smoke... when the smoke cloud cleared, I could see the Mercedes far, far behind me, the windshield wipers and washer going at full blast trying to clean the mess of his windshield... it is the funniest thing that has ever happened to me while riding the moto.
I bet he figured I had some kind of defensive smoke system installed - I also bet he has never tailgated a motorcycle again since that day.
Michael
Slydynbye
Will ride for Pie
So where should I put my Oil injector to ugh ...Duplicate this problem?
Couldn't have happened to a nicer Mercedes.... James Bond would be proud of you - Q, too. If you can figure out a way to replicate that at the touch of a button you might make a fortune selling that 'farkle' on the internet. Or you might get arrested for polluting the air.Note the picture of my bike above my name on the left hand side (the avatar) - when my bike rolled upside down into the ditch, a lot of oil got into the air filter. When I started it up, it smoked like a destroyer under attack in a WW II movie. I then rode about 300 miles to the city limits of Zurich - no problems - until I hit a big bump in a construction zone on the expressway, which was sufficient to bounce all the loose oil on the bottom of the filter enclosure into the carbs. There was a big Mercedes S right on my tail, about 30 feet behind me, and he just disappeared in the cloud of smoke... when the smoke cloud cleared, I could see the Mercedes far, far behind me, the windshield wipers and washer going at full blast trying to clean the mess of his windshield... it is the funniest thing that has ever happened to me while riding the moto.
I bet he figured I had some kind of defensive smoke system installed - I also bet he has never tailgated a motorcycle again since that day.
Michael
Well you live and learn.
Any idea why two pipes come back from the carbs to the air box, although if there's the sub air filter it's probably viccy verca, that is from the air box to the carbs. Is it some sort of balance?
I stand by to be edumicated.
Upt'North.
CYYJ
Michael
I think it might have something to do with North American emission control systems, but that is 100% a guess. I have attached a picture of it.
Michael
Sub-Air Filter Assembly - ST 1100
