Ken I tend to agree that it is on the feed line. I may have misled a little, it is more a flow restrictor/check valve to prevent blowing out the heater core during, um, "spirited" driving. It has an approximately 1/4" hole in the middle of the check. I think during normal driving flow is both around and through it. During high RPM usage the increased flow causes the check to close and allow flow only through the hole in the check. I have seen pictures of it installed so I know which line it goes into but I don't know if this is the supply or return line. I'm pretty sure it's the supply line but want to confirm before I refill the system with coolant. On an a slight tangent to this thread I had posted the other day about a positive way to confirm that the water pump was indeed pumping. Being an LT1 there is no drive pulley and the drive shaft is all but invisible behind the pump. I went ahead and pulled the front cover off of the pump and the shaft turns but the impeller was floating on the shaft. I'm glad I didn't run the engine for any length of time during my repairs and I now know what caused the blown head gasket that was on the engine when I towed it home. Now if I can just figure out the low oil flow to the rockers I think I may have overcome the big obstacles with the car. People that don't maintain fine automobiles should be shot! I could understand the lack of maintenance were we talking about an Escort or a Vega! Rant mode off. Frank, Indy
