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Discussion Starter #1
Ok, this is an interesting thing. 96 FXSTC, riding about an hour few days ago. Upon return, heard hissing from motor. Couldn't find source. Also smelled a distinct oder of sewer/methane gas. The order could've been excess chrome cleaner from earlier cleaning of dragg pipes, however I have never experienced that oder, only amonia type oder. The hissing possible from air escaping from new stainless oil lines recently installed by me about 150 miles ago, however no fluid leak and level good, and dip stick temp gauge 150. As a fairly experienced mech, certified FAA airframes, and all own wrenching for years, I am scratching my head. What would be a easy way of verifying oil pressure/flow? Concern is loss of former and excessive oil temp in cylinders/case.
 

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When you heard/smelled trouble, was it in a garage, or outdoors? If in a garage, are you certain it was the bike, and not something else in the garage?

You describe it as a methane smell, but have you ever smelled ozone? A starter or rotor that is starting to go can generate those odors.

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Discussion Starter #3
Ya, I've smell all you mentioned before. This happened twice in outdoors. First at convenience store 15 min prior to home. Both times same thing. Hissing and oder. Yes, definetly methane/sewer smell. I dissmissed it at store thinking it was there sewer, and couldn't identify where the noise was originating. Then as soon as I pulled in driveway, climbed off the bike, and immediately got the same oder and sound. Again, couldn't identify it. Bike was running fine. Had visible heat vapor coming off pipes 6 inches from cylinder, and I noticed some residual mothers polish. I've started it a few times since, but haven't ran it more that few minutes. I'm thinking that maybe I've got no oil pressure/flow, so cylinders and case is to hot, and producing gas when oil is beginning to boil. Can't think of anything else. Definetly not ozon/electrical. I'm thinking to redo oil lines to ensure no air leak. Maybe disconnect a particular line to see if pump is working.
 

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Hit it she goes boom
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Forget about low oil pressure, you won`t get any smell from that...

I think the charging system is overcharging the battery.
Yup, thats what I was thinking. I've had a car battery explode so what ever you do.. be friggin careful. Wear safety googles and protective clothing before you open the battery case or the area your working in.. no sparks or fire around it either. That car battery blew, scattered in pieces, the acid ate the back of my uniform. I'm lucky I had my back to it...
 

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VA Fender Bender
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you know I never believed in a potential problem, either I have a problem or I dont....

good luck
 

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Discussion Starter #8
Ok, sounds like a very good possibility. I'll use caution and check it out. I'll update when I figure it. Thanks Bros
 

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Stay away from the battery when you smell this, let the gas subside before you do anything on the bike, car etc.

I have a standby generator outside the house, it did not start when the power went out, so I went out and tried to manually start the motor. It cranked very slowly, so I opened the cover and reached in to the battery cable to see if it was tight, when I moved the cable the battery exploded. Felt like my hand had been hit by a sledgehammer.

Don`t ride the bike until you get this issue resolved. It could be a bad battery, voltage regulator, or both.

I suggest you start a thread over in the electrical section of the forum, the experts over there will get you going.
 

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Maddog
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Take a piece of 3/8" fuel line (about 2-3' long), put one end up to your ear and the other
end somewhere close to where you hear this noise. You should be able to pinpoint the
source of the hissing sound by moving the end of the hose around the area in question.

+1 on the battery too! Be careful, hydrogen gas is very explosive!!!
 
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