Help with Crate G10XL amp

[K2desoog]

I bought this amp from Swee Lee back in the early 90's. Its rarely used and sounds pretty well for its age.
However, the pots are crackly and I cant open the back covers to allow me to 'grease' the pots. Screws all rusted and jammed. Oiled (WD40'd) it but still no-go.

I'm a DIY person (cheapskate-lah!), sending it 'in' is not an option. Any ideas on how to grease them pots are appreciated.

Tks

 

[PatheinRaindropMoe]

pots usually are sealed. Other then opening up the pot enclosure, it might not be so easy to get inside

If to really open up the pot, then do take care of not greasing/wd40 the carbon ring of the pot. Within the pot, the only movable part is a wiper(connected to the main turning shaft) that is constantly in touch with the carbon ring. The carbon ring is the part with the resistivity and the wiper will rotate along this ring to vary the resistance.

Oil based lube(wd40) actually not a good idea for the those movable parts that has to do with audio path. The oil based sustance will attract dust to stick to it and somewhat reduce the conductivity between the wiper and carbon ring of the pot. Certain crackling sound when turning the pot actually comes from the wiper getting in and out of contact with the carbon ring due to worn out carbon ring or dust particle.

With audio path, this will be pretty obvious as the volume change from 0 to which ever volume level the pot is set as.

Do try those electrical contact cleaner, non oil based kinda

Worst ome to worst, if really wanna diy, try replacing the pots. The value and taper(noting the physical positon of the pot shaft and measure the resistance value) should be able to get it using multi meter.

 

[K2desoog]

eh sorry.. i shoudve made it more clear.

The screws for the back enclosure of the amps' electronics are rusted and jammed and I couldnt get them off. The only way that i can get to them pots itself is to 'force peel off' the covers which is a bad idea.

So without being able to get to the pots from the back, I'm looking for ideas.
I'll try to post some pics soon.

 

[K2desoog]

Here are the pics.
I think the only way i could access the electronics is to unscrew and open up the amp cabs. There are no openings at the back. The screws are all rusted and jammed.

The knobs can be pulled out and i tried to leak in some 'Singer' oil on the shafts hoping it'll get rid of any crud and smooth the contacts. It didnt work

 

[Dongara]

Yes, I see what you mean about rusty!

To clean the pots, try going to a hardware store and getting some electrical contact cleaner. Remove the plastic knob from the pots and spray the contact cleaner down the shaft of the pot and work the shaft clockwise and anti clockwise. Keep doing this until the pot frees up. If it is still stiff then leave the cleaner on the pot for an hour or so and try again. This should loosen the pot and stop most of the crackling.

Also spray some cleaner on a guitar jack and work it in and out of the input socket as these will be rusty too.

Hope all this helps.

cheers,

Mark.

 

[cmtan]

How to fix this buzz

To access the pot, teh whole panel has to be removed.
This panel is usaully held be the headphone sockets and the pots.

Once the panel is removed, replaced all the problem pots.
Using contact cleaner will help but the problem will probably return in a short while.

 

[relinquish69]

just spam WD-40 let it soak for a while. after that get a hammer and a screw driver to start hammering the screw head so that it's easier to get a grip. after that use 2 hands and a lot of force to start unscrewing. do it very slowly as we do not want to risk having broken screws.

Btw if you break the screws, have to bring out the drill already. just my suggestion.

 

[K2desoog]

just spam WD-40 let it soak for a while. after that get a hammer and a screw driver to start hammering the screw head so that it's easier to get a grip. after that use 2 hands and a lot of force to start unscrewing. do it very slowly as we do not want to risk having broken screws.

Btw if you break the screws, have to bring out the drill already. just my suggestion.

You're not serious are you (the hammering part!)?
I've soaked with lighter fluid, wd-40 etc. on one a couple of the screws but wont turn/budge. The screw head has been damaged.

>> cmtan,
you mean these.

and if i were to unscrew them, I'd be able to remove the panel & get access to the pots etc. A lot of work.
I'm inclined to let the amp 'die' natural death

 

[relinquish69]

i'm serious about the hammering part. It's to salvage the screw head. Alternatively once you can remove a little bit, use a set of pliers to twist it out..... with lots of WD-40. no need lighter fluid, that doesn't help.

 

[K2desoog]

I'm letting this amp go cos I just cant find the time to try to fix the crackly pots.

So if anyone wants to buy it, just drop me a message & your "cut-rate reasonable offer/price".
In the meantime, I'll just let it "stand at the corner".