Heat Problems....

[acklac7]

Ok I have been getting horrible heat for about the past month...so I read some posts and went out today and checked the heater outlet and inlet hose, and found out that their is good flow from the Inlet hose but little or no flow from the outlet hose....Does that mean the heater core is clogged? also something strange keeps happening.....when ever I go through a car wash with a under car wash the heat all of a sudden starts working...strangest thing I have ever seen ......also if I need to flush the heater core will can I just remove the inlet & outlet hoses and then flush them? or will coolant come spewing out of them? thanks

[Ranger]

I seem to recall Bill saying that the heater core is not high flow. That being said it couldn't hurt to flush it. If you remove the heater hoses and flush the core you will undoubtedly get some coolant spewing out. Attach a length of hose to the outlet side and route it over the fender on to the driveway/road or into a bucket.

[rjhat]

If you have water going in, but not out, your heater core is definitely stopped up.

You can try this. Remove the hoses to the heater core at the firewall. spray water from a hose into the return side of the heater core first (this means that water will be going opposite direction it normally flows through th H.C. When the water coming out of the other connection is clear, put the hose on it . Go back and forth between connections until the water is clear. After this, use a rust removing solvent to flush the heater core by attaching a hose to one of the connections on the firewall and pouring it through a funnel. Rinse the H.C. out with water and replace hoses. You will probably lose a lot of coolant doing this, so make sure you refill it before you drive it. Good luck. I did this today on a ford.