Winter EOC while not losing heater

[3dplane]

My heater core is restricted so I'm only getting barely noticable heat due to insufficient circulation. Flushing my heater core makes it a little better for a day or two then back to practically no heat.

I simply don't have the time right now to replace my heater core for this concern and I just did not want to use any chemicals in case it eats the radiator or my heater core.

So I had this idea to obtain an electric auxiliary coolant pump and hook it inline with the heater core to help circulation and see what happens.

Pump (used) ebay $40 to the door plus about $12 at auto parts store for a few 5/8" to 3/4" heater hose adapters and hose clamps. ( I had hose pieces)

Tested the pump's power draw: Dry,unloaded an amazingly little 185mA!!!(less than 0.2 Amps)
Submerged in a bucket of water 1.2Amps.
Installed in the car, engine on or off 0.9 amps!

Before installation I had one heater hose disconnected at the firewall and had a helper start the car for a moment to see where the coolant is shooting out to determine direction of flow. (car's heater core inlet hose goes to the middle of pump and discharge port of pump (on it's side) goes to heater core inlet on car)

Not only do I have a working heater now but once up to operating temp I can EOC with the key turned back on for blower operation and the heat "never" goes away during my coasts.

I tested how long would it take for it to run the heat out of the shut off engine and I lost patience after four minutes. It have not dropped noticable temperature (sitting on my yard).

I thought some of you in the colder climates doing lots of EOC might want to think about giving it a shot if you lose your heat during EOC! I'm very happy with it especially that it draws less than one amp plus my blower of course!
Hooked it up to a switch on my dash.
Barna

[redpoint5]

Smart idea! The only heater core I have replaced is from an old Ford Ranger and it only took about 15min to complete. I'm guessing yours is more difficult to get at.

[JethroBodine]

Thanks for this. I've been wondering about doing this, as I've stopped EOCing most of the time for that very reason. I have to say that at -27 f, it does cool off pretty quick.

[brucepick]

Nice fix.
There's always the possibility of additional battery power to support a fan during EOC, if fan + EOC tends to reduce your battery voltage.

Of course if you're exposed to -27F like JethroBodine, I think there will be some significant costs to keeping warm no matter how you make it happen.

[3dplane]

Originally Posted by redpoint5

Smart idea! The only heater core I have replaced is from an old Ford Ranger and it only took about 15min to complete. I'm guessing yours is more difficult to get at.

Thanks! Yes mine is in the A/C case burried under the dash.All of wich would have to be removed and disassembled. Alldata says 4 hours but the way they've been cutting labor hours lately I know it is more like 6 hours. I'll do it when it develops a leak. The auxiliary pump took me about 40 minutes to figure out where to put it and install it.
Barna

[3dplane]

Originally Posted by JethroBodine

Thanks for this. I've been wondering about doing this, as I've stopped EOCing most of the time for that very reason. I have to say that at -27 f, it does cool off pretty quick.

No problem! Just a reminder,the coldest morning I tried it here in FL was actually 27*F (not -27 ) but it could possibly make a bigger difference in your case! Oh and BTW it came off of an 07 Jetta according to the ebay seller : )
Barna

[Daox]

Originally Posted by brucepick

Nice fix.
There's always the possibility of additional battery power to support a fan during EOC, if fan + EOC tends to reduce your battery voltage.

Fans don't pull that much power that it would be a problem. Headlights are much worse.

[oil pan 4]

I have found 5/8 heater hose fittings all too often will have rubber restrictors in them.
Over time the rubber restrictors break down and could break off from one fitting and clog another.

[Gasoline Fumes]

An old diesel Mercedes will have a pump like this too.