Re: Draining 5KTQ cooling fluid

[Mark Eissler <tequila@interlog.com>]

Paul Hill 223-2154, hill@eng.pko.dec.com wrote:

>
>Anyone got any tricks on how to completely drain the system?
>
>Bently says to "loosen the hoses..." on the thermostat housing and heater
>supply, but that does not seem to drain much.  As I want to change the 
>coolant
>type, I would like to get as much of the old stuff out as possible.
>

In that case, you should completely flush the system with clean water. 
This tends to be a pretty messy procedure.... Set your heater controls to 
warm, pull the heater hose that leads into the thermo. housing. Pull the 
hose from the top of the rad. With the overflow hose pulled from the 
bottom of the rad, direct fresh water into the top of the hose until it 
runs clean (coming out of the bottom).

Next, direct fresh water into the top rad hose (that's still connected to 
the water outlet on the engine). This will flush the engine and the 
heater core. (It's important to have the heater controls on warm for this 
procedure to work properly).

Don't forget to flush the expansion tank as well.

Connect all hoses, fill with coolant (50/50 mix). Let car run at high 
idle for a few minutes. Turn off, check level and top up if necessary.

Back the car out of the garage (or wherever) and hose down the area to 
get rid of all that coolant that didn't make it into one of the ten 
buckets you had placed under the car. Usually, this equals about 50% of 
all the drained coolant!

Drive for a week and then finally make the time to spend a couple of 
hours figuring out which hose clamp it is that you didn't tighten 
enough....

Hope this helps!



Mark Eissler          | UNIX, DOS, oh and MacOS too.
tequila@interlog.com  | Why wouldn't a developer use 
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