Flushing heater core

I, too, amd battling overcooling problems. After eliminating the other obvious problems, and reading Willye's post, I'm targeting the heater core. Want to give that sucker a good flush.

Has anybody done this directly? I'm wondering if anybody has any suggestions/tips/tricks regarding access and such. The FSM just says to connect hose to the line coming off od the water pump, and to disconnect "another line" for exhausting the water.
Of course getting to the line off the water pump is easier said than done, but I'll figure something out.

Question - does it matter which direction the water is pushed in? FSM says from pump line into core, but it'd be easier to get hose into the other line to do it backwards.

Let your engine warm up and turn on the heater full blast. You've got the line going into the heater core and the line coming out. The line coming out will be cooler than the line going in. You want to back flush it by hooking a hose to the line coming out (cooler line). It does make a difference. It's not much use to try to flush the core through the line going in (hotter line) because it is already clogged up on that route.

I had to take my Escort again this year to the shop to flush. Right after they flushed I had good heat. NOTE: I told them to concentrate the flush on the core due to insufficient coolant flow. Once they did that, I had good heat. Also note that even if you have good flow through the core, you may not have good heat. The shop flush uses very HOT fluids to flush with. It likely removes sediment in the core and improves heat transfer. I do not believe you will be able to do this yourself unless you own a shop with the correct tools and flush material. The design of the Escort temperature sending unit in the coolant line is not good. It shows overcooling when really it is bad flow. Good luck!

I flush mine at home all the time, they dont use hot water or hot liquids, the only hot liquid is your coolant coming out when the thermostat opens.

willye, what does the shop charge to flush?

I just flushed mine and it has better heat. The procedure I used:

1. 6 ft 5/8" heater hose on the IN tube (driver side)...hose goes in big bucket.
2. 1 ft 5/8" heater hose on OUT tube (pass side)...garden hose nozzle in this.
3. Flush away for 50 gals....dispose of dilute antifreeze properly.
4. Pour CLR cleaner in the 1 ft hose with a little water...hold 6 ft up to keep CLR in hose...wait 10'.
5. Flush away
6. Repeat 4.

Next I may try "real CLR"....I used generic stuff. May hook my garden hose up to the water heater (in lieu of normal faucet)...140*F water may help alot.

Heater core prices aren't much for the 1.9L. $30 at autozone with Lifetime warranty.