Cascade Crew

blue89 · Posted: Tue Dec 30, 2008 5:56 pm Post subject: Heater core return

Maybe some of you old school guys can help me figure out what to do. The 454 has a feed line for the heater core and the 454 radiator dealt with the return. But now that I'm using the newer radiator I don't have the return! What do you do with it now? The V6 water pump had the return before. There are some extra bungs on the 454 water pump, can I use them?

Twilightoptics · Posted: Tue Dec 30, 2008 6:06 pm Post subject:

Water pump should have an outlet. Is it a short pump style or long?

Out of the intake, into core, into pump.

blue89 · Posted: Tue Dec 30, 2008 8:21 pm Post subject:

I don't know if it is long or short. Seems pretty long to me! There are two fittings on the water pump. One goes to the intake and the other is plugged. You can also see the heater core feed to the left of the thermostat housing. Sounds like I should use the extra water pump bung?

chevymad · Posted: Tue Dec 30, 2008 8:53 pm Post subject:

Put a nipple in the plugged hole. It should be a long water pump. All the 70s stuff was I think, except perhaps the corvette.

blue89 · Posted: Tue Dec 30, 2008 9:03 pm Post subject:

Excellent! Thanks a lot guys. I'm new to all this "old" stuff. I've seen those nipples at the parts store. I'll grab one and go! Is that the intention of the bungs?

chevymad · Posted: Tue Dec 30, 2008 9:06 pm Post subject:

Yes, the one nipple is always used for the bypass though. I have heard of people blocking that off, but chevy intended a bypass. The other plug is for the heater core, unless you have the radiator nipple. I'm really not sure why chevy changed that. I've worked with alot of 67-72 trucks.. the earlier ones are plumbed to the water pump and the later ones to the radiator.

You're actually kinda lucky, looks like someone used the hex style plug in that water pump. Much easier to remove. Many times they either have a square head, which you can still get out fairly easy, or worse case.. an allen or inverse square. Those always seem to round out.