[Axnjxn]

The one from the water pump goes into the top heater core pipe, and the one from the intake manifold goes to the bottom pipe.

If you reverse them, the heater won't work for beans.

 

[2c1965]

The top hole has the hose that goes to the water pump.
The bottom hole is for the hose that comes from the block behind the thermostat.
The bottom hose goes by the choke (hot fluid from the block).

 

[laynrubber]

I was going to answer this since i thought i knew the answer...........maybe now i don't.
I can see the hotest hose going past the choke, but why does it matter at which port the hotest hose enters the heater core. I would have thought the pressure would make the coolant flow thru the core any direction, thus giving off heat ?

 

[CanadianClassic]

Thank you everyone, I will put thoose hoses on now before I forget where they go again... =)

 

[Axnjxn]

I thought this was the case as well. A heat exchanger is a heat exchanger, right? Well, some are directional, and the only thing I can figure is that the pressure isn't high enough to overcome gravity, or the heater core in fact has some sort of baffle system in it. For whatever reason, it doesn't work flowing the other direction.

 

[Gas_Pumps]

If you reverse the hoses, The suction is at the bottom. The rest of the core could trap a lot of air and the it would be tough for the water pump to get it out. The coolant coming in the top would drain to the bottom making for a mostly air filled heat exchanger. Is that a reasonable argument?