JEDI87

Ok,my heater is blowing out semi warm air.I checked the coolant,fine,valve fine,I then noticed that the heater core hose in the engine compartment,on the left,is cool while the one on the right is hot.Could it be blocked?I'm not sure which one is the in and which one is the out.

ChickenLover

Sounds like it's blocked to me. I'm actually in the same boat as you right now, so when you figure it out you can drive down to Reno and fix mine too.

I'm about to take mine apart and try to clean it out. Perhaps by blowing some compressed air through it. I haven't really examined it too closely to be honest. So if I figure it out before you, I'll be sure to let you know what it was.

leebee

just use a barbed fitting and your garden hose to try and clear the blockage. sometimes compressed air can blow out the hose, especially if it has a weak spot. take both hoses off the heater core and use the hose to flush from one side then the other, that should get out any build up from inside the core.

lee

JEDI87

Yeah I was going to try the garden hose thing too.We just got a foot - foot and a 1/2 of snow so I want to get the heater fixed.Right now We're driving the 87 but a rear facing baby seat in the back is a pain in the butt to get in.Chickenlover,I'll let you know what happens.

3car

my guess is that it's clogged by corrosion in the cooling system, and flushing with a garden hose or compressed air wont work. i would get some chemical cooling system flush and a prestone flush kit and clean it out that way.

Babypig

Flushing it with chemical would be the last thing I would try after trying to flush it with just water. Undo both hoses and flush it both ways lots. Don't spare the water. The crud will pour out no doubt. Just don't run the flush through the entire engine on a runner that old. You may take out something thats just barely holding together.

3car

to each his own, but if water being pumped at the heater core at 190 degrees wont flush the crud through it, the water from your garden hose probably wont do much.

Babypig

Mine ended up having a fine silt in it and with all the hoses that the fluid has to go through there really isn't as much pressure going through the core as you'd think. It's very easy for the bottom end to get gunked up, as it's an upright style heater core. The dynamics allow the silt, gunk, whatever to filter and fall to the bottom of the core when there is no water movement. It worked for me, Just saying start easier and go from there.

JEDI87

Good news,It's fixed.I took the heater core hoses off and flushed the core out with the garden hose and gun.It pushed out all kinds of crap.Needless to say,I got wet.Now the heater pushes out really hot air!

ChickenLover

Good to hear. I fixed mine today as well. My problem was that the linkage that connects the valve to the temperature lever had busted off. I zip tied the valve open for now. My heater breathes fire now!

JEDI87

Yeah mine is so hot you almost can't put your hand in front of the vents for too long.I also found out why my rear heater isn't working,one of the lines going to the rear heater core is clogged really bad.I flushed out the rear core and other lines but the one is too clogged.

leebee

cut out the clogged line and replace it with high pressure rubber hose and you shoudl be good to go. my old 86 lines had corroded at the engine bay, we cut them off front and back, put in the hp hose and voila, more heat than i knew what to do with!

lee

JEDI87

I had to dremel about 2 inches off the top of one line,too corroded to clear out.I tried using compressed air for the rest but no go.I thought of using rubber hose but didn;t know if it would work.I may just get another line from a wrecking yard.