What's the best way to bleed the air from cooling system - I don't want the water to get into the Opti-spark when bleeding - what have ya'll done to keep this from happening.
Thanks

 

I believe there is a bleed screw on the throttle body on the LT1s. You can also try pumping the upper radiator hose some until it fills with water.

 

There is an air bleed valve on the top of the thermostat housing. It faces the pass/side of the engine. A small brass screw can be backed off slightly to vent air from the system. Just barely open it so as not to allow coolant to drip on to your opti-spark. This is done with the engine idling. May take a couple of shots.

 

I checked the raditor through shroud and appears clean - my tempature varies quite a bit. Doesn't really get hot just 195 through 210 when not in traffic. I know both upper and lower raditor hoses were replaced before I bought the car so I think there may be some air pockets. I'll try bleeding the system. Any tips for keeping water away from opti-spark?

 

The few times I've changed the coolant I just barely loosened the bleed screw on the thermo to let any air escape. Did this with the engine running. After shutting down the engine I fill the overflow container to the hot line. You may have to repeat this a couple of times. Worked for me.Some prefer to remove the bleed screw & fill the system until coolant runs out. If you use this procedure make sure you cover the opti.