Gorilla GG-20 output problem

[chirhomin]

Ok, so I was rooting around in my parents' attic and found my very first amp, an old Gorilla GG-20 30 watt amp.  I plugged it in, plugged my guitar in, and nothing happened.  I hooked up my headphones to the headphone jack and it worked.  However, it sounds like my pots must be really dirty, cause it was crackling and buzzing and popping every time I adjusted the volume, gain, etc.  Any ideas on where to start to resolve this problem?  I bought a multimeter shown in the multimeter video on this forum, but I'm at a loss for where to start troubleshooting.  Thanks for any suggestions!

[DrGonz78]

Clean the headphone jack to make sure dirty contacts are not shunting the speaker signal. So it works with headphones but the pots are dirty. Get some Deoxit or other type of cleaner and spray out the dirt build up in the pots. Also, would be a good idea to make sure the speaker output wires are really connected.   

[Roly]

Yep, sounds like dirt and oxidisation in your pots and the switch contact in the headphone socket that turns the speaker off.  Metho will also serve as a pot and socket cleaner if you can't get a specific product.

[chirhomin]

Thanks, guys!  I will try it this afternoon!

[GIMAGUITARS]

NOTHING SCREAMS LIKE A GORILLA.  For those of you who have never owned or seen a Gorilla amp, this is the slogan on the sticker they placed on the back of the speaker. http://s1325.beta.photobucket.com/user/GIMAGUITARS/library/