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03/28/2010 @ 7:14 PM                          
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Posts: 36
Joined: 08/10/2009

Today was the first time I took it out this year. I warmed her up gently, let it run for about 10-15 mins before riding. Within the first 1/4 mile, she was stalling out -- could be fuel, the main tank may be empty, was running on Reserve -- and I was on my way to the gas station.

When I got to the gas station, I look down and there was oil all over the place coming from as far up and back as the air filter. It was like a bomb went off with this oil -- all over the back of the engine (under the carbs),  all over the area just below the air intake. Behind me was a 1/2 mile trail of oil from the back tire, which explains that slip I felt on the past few turns. I stopped at the gas station and the bike made an 1-foot by 3-foot oil puddle under the bike. That's when I called for a tow.

Oil pressure light never came on, except when the bike had stalled out. Restarted, no oil pressure light.

What do you suppose this is? I'll tell you now, all the oil was behind the engine, nothing up by the head gasket, nothing fore or above the carbs. tons of oil, all on the left side of the bike, between the carbs and the junction box, covering everything from the as high as the air intake. No obvious point of origin, except maybe the air intakes just aft of the air filter.

Here's some photos of the problem:

2001 Kawasaki Concours

1983 Honda Interceptor
1981 Honda CM-400 Custom

03/28/2010 @ 9:39 PM                          
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Posts: 14
Joined: 12/22/2009
My '01 (Old Blew) leaked gas into the #1 cylinder, hydrolocked, and broke the connecting rod which went through the engine case.  It put down an oil slick a quarter mile long and had plenty left to puddle in my pickup truck, driveway, garage, etc.  I hope your engine is fixable.

I had the same symptoms - low in gas and oil everywhere.

03/28/2010 @ 10:02 PM                          
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Posts: 32
Joined: 07/16/2008
Probably you have a carb flooding over. It can run into a cylinder & past the rings, then overfilling the crankcase. When the crankcase is overfull, the crank & rods splash in the oil & will force it into the vent that goes to the airfilter. Check the oil, it may still be overfull & will smell like gas. You probably need to fix the petcock (unless it was left in the prime position all winter) & have the carb floats & needle valves looked at as well.  It could have hydro-locked & wrecked the engine, it sounds like you may have got off easy!!

Don  Marysville, WA
87  C10 170K & ready to go!
COG #8771   CDA #299-Damn Vandals

03/29/2010 @ 6:31 AM                          
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Posts: 36
Joined: 08/10/2009

Oh man, this talk of hydrolock is making me worry!

I followed the oil streak from the gas station back to the point of origin. It started leaking probably a mile, mile and a half before I stopped her at the gas station.

Let me ask this. If the engine hydrolocked and caused enough damage to account for this oil spill, would the bike have kept running? Because it was running, all the way to the station, more or less sounding and feeling fine.

And next. The bike had been idling fine for 15 minutes before I hopped on and took it down the road. Totally dry conditions -- no rain or puddles today.

Most of the accounts of hydrolock I read about seem to occur after a large amount of water gets ingested quickly -- i.e., driving through floods. Seems like, Hydrolock occurs, you throw a rod, and bingo, the engine won't run. In my case, the engine did run, long after it started dumping oil, all the way until i turned it off at the gas pump.

Then again, it did stall out 2 or 3 times after the oil started dumping, but the engine would always restart.


2001 Kawasaki Concours

1983 Honda Interceptor
1981 Honda CM-400 Custom

03/29/2010 @ 6:53 AM                          
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Road Bike
Posts: 357
Joined: 05/30/2008
Actually hydrolock occurs when gas fills a cylinder and the engine is started, with the starter motor turning the engine over to try and compress the gas and the rod is damaged.

Do you smell a lot of gas? This seems like the most likely solution. The engine can run even if you have gas in the oil though it won't run forever- the oil is diluted and the engine will be damaged eventually.

Do you smell gas?

David in Jax COG# 7898
preparing resumes for COG
members and friends
I ride a KAWASAKI ZZR1200 -

03/29/2010 @ 8:36 AM                          
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Street Cruiser
Posts: 652
Joined: 05/07/2008

hydro lock occurs when any liquid gets into a cylinder in sufficient quantities.  Does the starter motor have enough power to bend a rod by itself?  I though that one of the other cylinders had to fire to bend a rod.
Plus 1 on gas in the oil and excess being expelled through the breather on the valve cover and into the air box.  Pull the air box cover and see how much oil is in there.  I had a leaking float valve last spring, and gas would run out of the air box when I shut her down.  She ran like crap at idol but would smooth out at speed except for back firing during decl.
Petcock was ok so escaped the hydrolock.  Got lucky.

"If it hasn't killed me yet, it's runnin out of time"

COG # 8062
AMA # 1084053
ROMA or Scarlet harlot acording to my wife

03/29/2010 @ 9:41 AM                          
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Posts: 116
Joined: 07/14/2008
I had this problem on my '88.  Caused by both the petcock and #1 carb float valve gumming up at the same time.  Gas will run into #1 cylinder past the rings and into the crankcase - filling up the crankcase.  The engine will start and run fine until it begins to build up crankcase pressure at which time the gas/oil mixture will be forced into the airbox and out the water drain tube.

If you're lucky and don't have a full tank the gas will drain into the crankcase and not cause hydrolock (gaslock?).

Continuing to run in this condition will destruct the engine since all the oil is washed off the lower bearings.

Hydrolock occurrs when the gas either doesn't leak past the rings or you fill up the crankcase with gas left in the tank.  Yes the starter motor will not bend the rod.  The engine has to fire to bend rods.  On just the starter motor you hear a loud clunk and it stops turning over.

The fix is to rebuild the petcock (K&L makes a rebuild kit) and clean the float valves thoroughly, including the seat in the carb.  If you don't clean the seat thoroughly you will have to take the carbs back off and clean them again (ask me how I know this).

Since that happened, several years ago, I aleays park the bike on the centerstand when it is going to be parked for several days and it has not happened again.  I think parking on the side stand (leaning toward #1 cylinder) may have added to the problem.

03/29/2010 @ 11:30 AM                          
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Posts: 1407
Joined: 10/30/2007
Even though the above causes are likely do not over look silly things like oil drain plug being loose or the oil filter being loose or any number of other places oil can leak from.

South Central Area Director
My Photos

03/29/2010 @ 11:57 AM                          
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Training Wheels
Posts: 71
Joined: 05/07/2008
plus one on always parking on the center stand if possible. I have cleaned carbs on bikes that were always parked on the side stand and you could see the gas "ring around the tub" that was at an angle. I would assume that it puts more pressure on the # 1 carb.  

COG # 8216
CDA # 0216

03/29/2010 @ 7:12 PM                          
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Posts: 854
Joined: 10/30/2007
I will just make a quick post as I'm on the bus.
The issue your having is not the leaking of gas into the sump or it's very unlikely.
If that were the case as soon as you put any revs on the engine it would imediately begin puking oil out the crankcase vent.

More likely it's some other issue.
As others have said remove the filler cap and have a sniff you will smell if there is gas in the oil.

The other quick way to find out is to remove the air filter it will be a mess in there if you have pumped oil into the airbox.

If you did drain a bunch of gas into the engine and it sat there long enough the gas will seep past the rings and none will be left to hydrolock the engine so no bent rods etc.

The engine will not hydrolock once it's running unless you ingest water by riding into a river or pond   it only happens at startup. Sawfiler yes the starter does have enough umph to bend a rod. The issue is that Ma K. Did not fit a clutch on the zg1000 hence when the piston locks up as it can't compress fluids only gases something has to give and that's the rod.

The next Concourier has an article on how to fix a bent rod if you are unfortunate enough to get one.

take a good look on the lhs of the bike. It's possible you just blew out the gear change oil seal.

Good luck


Colin Prior
COG IT Officer

Lake Forest Park WA

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