[oletrucks] brakeline mystery

[ME1STKING@aol.com]

Three years ago I tore The brakes off and then put them back togeather again. 
 Today I reactivated them for the fist time.  Mystery is at the back of 
master cylinder on the line that goes forward there was a T fitting, with an 
extra opening. The assembly manual doesn' show such a thing. Is  there any 
possible reason for this ?
Perhaps the T is for something else, but can't think of anyplace to put it.  
54 3100 
Thanks, BK
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