[QUOTE=zgator]Thanks for the info crossfire.I guess you should know if you have a crossfire also. I went to Advance and they had one for $29.00.It says for heat only. I've got ac but I beleive the air is connected to a junction. The pump had one hole for the hose and one hole that has threads in it and it comes with a plug. Is this the pump I want???[/QUOTE]
Just changed mine on a 79. You do have to remove the A/C compressor bracket to get it off (real pain in the ***, as it has bolts in the exhaust manifold in addtion to a couple into the head and then a support bar down below. DON'T unhook your A/C hoses...just lift the compressor out of the way a bit - the reason you do this is it shares mounting bolts with the water pump. My solution - good bye A/C, wasn't working anyways and I don't drive the car with the roof on.
The "heater only" pump you got is correct. That refers to the side port on the pump. It comes with a plug sealed into the top and a threaded port on the side for your heater hose. Before you do anything else, remove that hose fitting with a 7/8 inch wrench prior to pulling the pump off the block. It is in there tight (if like mine). I cheated and used an impact wrench - came right out.
have fun and good luck. Seal it up good with RTV or Permatex #2 when you put the new one in.
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C3: 1979 Corvette Coupe, Auto, L-48, Red/Doeskin (my wife's fave);
C4s: 1986 C4 coupe (SCCA road race car), satin black, 4+3, Z51 package, L-98; & 1993 C4 coupe, white, 6-speed, LT-1.