Stubborn rusted screws/bolts

[62BT7]

Hello all,
I'm replacing the switching relay for my BT-7. For those not familiar, it's a smallish metal box on the left side of the engine compartment partially concealed by an air hose. It has 8 wire terminals, 4 on each side, attached via small screw-on terminals.

Problem/Question: I have tried to unscrew each of the 8 terminals and since they are bare metal terminals, you guessed it, they have rust on each one. Not corrosive huge amounts, just a thin veneer of rust, enough to make removal impossible, at least so far. I've tried different size screwdrivers, Liquid Wrench, but no luck getting them to budge. Tapping the center lightly with a center punch isn't feasible (these are small machine screws unsupported by anything) nor is heating via a blow torch (it would melt the wire insulation). I can think of a brute force solution, cutting the old terminal ends off and bludgeoning the screw out, but that'd be really tedious to do 8 times. Thought I'd ask for ideas. Any out there?
Thanks,
-Tom

 

[roscoe]

Tom,
there are any number of good penetrating oils on the market. Wet each screw and allow to sit at least overnight. If you are patient and use a screwdriver that is not worn, and of the correct size, I'm sure you will be able to get them out. Just keep them wet with penetrating oil. There is not much thread holding them.

Jon

 

[LarryK]

That's the idea soak and slow, patience, patience, patience.

 

[Keoke]

In addition to what Jon suggested what you need is a torque screw driver. Sears had one very reasonably priced;~$10.00, that has a pistol grip handle and the bits store in the handle too. Be very careful with that "Switching Relay" they be very expensive--Fwiw--Keoke

 

[Ed_K]

In addition to soaking the screws, if you can't get them to budge with a screwdriver, you may be able to clamp around them with the smallest vice grips since they have a substantial
thickness of metal in the head. If you can clamp on the small set of vice grips you can break them loose then run them out with a screw driver.
... If you can loosen the two screws that mount the relay to the car, you can lift the relay away from the fender and then get a dremmel tool with a cutoff wheel in there to cut the tabs right off of the old relay . You did say you were replacing it.You can then clamp onto the tab of metal and the screw that is still attached to each wire to loosen them up one at a time.