radiator heater hose question

[70chevytruck]

So my new radiator doesn't have an inlet for my 3/4" heater hose.

Other heater hose goes to intake manifold. Where can I run this heater hose to.....the water pump?

[D-rock1981]

Yup

[FirstOwner69]

Run it to a nipple on the passenger side of the water pump if you want to duplicate the original setup on a 70 with a small block.

[SS Tim]

IIRC Automatic and A/C trucks returned to the radiator for better overall cooling and base trucks returned to the pump for quicker warmup. Going have to go look that up.

[old Chevy guy]

That's where it goes on my 71. Water pump that is.

[davepl]

Originally Posted by SS Tim

IIRC Automatic and A/C trucks returned to the radiator for better overall cooling and base trucks returned to the pump for quicker warmup. Going have to go look that up.

I've only seen 6-bangers return to the radiator myself in the book. I know my '70 AC truck is the same as any other 1970 GM car, the lines run to the water pump and intake manifold.

[Jonlopes]

My 71 396 with AC returns to the radiator. I don't suppose it matters too much.

[FirstOwner69]

Actually, I think through 1970, at least on small blocks, the 5/8" hose went to the intake and 71s and 72s had one hose (not sure which one) to the radiator. That's based solely on my 69 with A/C and TH400, observations from this forum and some junkyard trucks. It may vary depending on which radiator size (number of cores/rows) is used. Mine is 4 row.

[SS Tim]

Like I said I still need to go look through some documentation. But here is a 72 fsm page showing the radiator return on TH350/400 trucks.

Originally Posted by 70chevytruck

So my new radiator doesn't have an inlet for my 3/4" heater hose. Other heater hose goes to intake manifold. Where can I run this heater hose to.....the water pump?

Since the OP states his "new radiator" does not have the inlet for the heater core outlet hose it be safely assumed his old radiator did.

[davepl]

Given my factory Harrison rad doesn't have such a port, don't know what to tell you. Maybe it's because I have AC.

I still think it's a terribly slow way to warm up an engine, as it bypasses the thermostat. I don't get the design at all.

[MagmaJct]

Originally Posted by davepl

Given my factory Harrison rad doesn't have such a port, don't know what to tell you. Maybe it's because I have AC.

I still think it's a terribly slow way to warm up an engine, as it bypasses the thermostat. I don't get the design at all.

It makes sense if you think about it. The coolant leaving the heater core is passed over the ATF heat exchanger to pre-heat the ATF. Very little cooling occurs, as the coolant leaving the heater core is returned to the same side of the radiator that leaves the radiator. That is, the coolant leaving the heater core does not pass through the radiator core, so it receives very little cooling.

Regards,
Mike