Heater hoses

SShank42 · #1 (**permalink**) 12-19-2007, 11:31 AM

1987 BII with a 2.9. Does it make any difference which way the hoses attach to the heater core? Does the pass. side core hose go to the nipple nearest the thermostat housing or the other way. I'm fighting a not much heat issue. I have the Prestone flush kit installed. So I undid the the hoses from the kit and could easily blow thru (by mouth) all four sides of the hose and watch it blow out the other ends. So I am assuming no blockages. So then I started it up with the hoses unhooked and had good flow from one hose. Normal right? I also replace the thermostat and checked that the heat control valve was working properly. Topped everything off and made sure to get air out. Still only like warm heat. So I is it possible the heater hoses are backwards? Thanks

5.0B2 · #2 (**permalink**) 12-19-2007, 12:22 PM

The heater core isn't directional - sorry. Try pulling the core cover off and checking for something blocking the air flow.

SShank42 · #3 (**permalink**) 12-19-2007, 12:37 PM

That what I thought but wa not sure. Air blows strong out the registers.

Help I M Stuck · #4 (**permalink**) 12-19-2007, 02:16 PM

all the heater core is-is like a extended hose with fins..it dont matter which way they go. God knows i've replaced plenty of them and never remember which is when when i put them back on. Never had any problems.

plilikoi · #5 (**permalink**) 12-21-2007, 01:02 AM

It sounds as though the heater core is blocked. You can't expect being able to blow through the hoses, especially by mouth, to be a fair test. Air passes through restrictions much easier than water and you can't begin to mimic the volume of fluid that passes through the heater core. I would hook up a garden hose to one side of the heater core and pulse the pressure, turning it on and off in very short bursts. Ideally you'd hook up the water to the outlet side of the heater core lest you make the blockage worse. Fortunately, the heater core is cheap and easy to replace on this vehicle.

SShank42 · #6 (**permalink**) 12-21-2007, 08:39 AM

Make about the volume, never really thought about that.Guess it could have a restriction. It would suprise me thought. The whole cooling system is new after the reman engine went in. Actually I have replace the heater core twice since then. They kept splitting down the sides. Not sure what was up with that. Like you said they are cheap and easy. 30 min. or so and it done.