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Levinson 331 leaking black tarry material

My trusty old levinson 331 has been collecting dust x 2 years. It was left unplugged in upright position. Last week when cleaning around it, i noticed thick black tarry liquid was spewing out of the power cord socket. I removed bottom panel and found more of it on the inside of the rear panel where the connectiins for power, rca, communications link. I was guessing electrolytic fluid from one of the caps but i doubt it. Gravity shoyld have pulled the liquid down onto the bottom panel right??? Not a drop there. I remived the top panel also but that did not reveal anything. No rubber or plastic melted from top panel. Or gaskets. Is there an easier way to post pictures? Not sure i still have photobucket.
chenglo1
ebm
9,311 posts
 
Better get it checked out before it starts smoking and blows up!!
teo_audio
2,197 posts
 
If it has a slight ammonia smell, then it might be electrolytic fluid (dried up) from one of the main power supply caps. It tends to be quite easy to smell. Much in the direction of a stale urine smell.

However, a quick look at an open chassis of this amp illustrates that it is likely the black glue material they used around the periphery of the plug and metal plate interface. It may have originally been viscous/tar like... and not like a solid epoxy, and might move around from heat exposure and time.

If it’s been moving around, then this amplifier might have had a little too much heat exposure while in storage. Capacitors age from heat, whether the capacitor is in use or not. The scale/chart for the aging of capacitors from heat is not linear, it’s almost exponential. It is a notable part of why thermal management for audio gear is such a big deal.
mikld
105 posts
 
Has your ML331 recieved the "331.5" upgrade?
dweller's avatar
dweller
3,781 posts
 
The power transformer is sometimes "potted" in tar to stop noisy vibrations. What temperature was it stored?
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