: 87 brougham d'eligance - Coolant system flush



outsider
03-30-11, 10:53 AM
So I get my car out of storage sunday! :devil:

Anyways, one of my major projects for this car this spring will be to replace the water pump and thermostat, as last summer I had a "Coolant temp" warning light come on when using the AC once...Didn't like that. My coolant has had sludge in it that looks like it might be rust...I know it's not a head gasket leak or anything because I've had compression checks done and they all checked out.

Anyways...What's the best way to flush the cooling system to get rid of any sludge build up or rust?

sven914
03-30-11, 11:39 AM
Probably irrelevant, but my car used to the same thing. It never overheated, but the coolant temp light would periodically come on. The problem was the temp sensor.

As for the flush...

There should be a petcock on the bottom side of the radiator; open that and drain the coolant into a bucket. Then take a garden hose and refill the radiator, allowing the water to drain. You can back flush the heater core and engine coolant passages by removing the lower coolant hose (drain into the bucket) and one of the heater hoses. Put the hose to the heater hose you removed and keep it there until "clean" water drains from the block. Reconnect all of the hoses, refill the engine and radiator, and then bleed the system of air. **Note: you may want to do the heater core with the vehicle facing down hill.

outsider
03-30-11, 12:13 PM
Thanks Sven. I've done the radiator flush a few years ago. The block flush is what I was interested in knowing about. Was wondering if I needed like a special chemical flush or anything to clean it out.

Anyways, I will do this block flush before I start replacing parts. BTW, where is the temp sensor located? I have the FSM at home but I am not at home. If you don't know off the top of your head that's ok, I can check the FSM when I do go home. Thanks ;)

intragration
03-30-11, 02:51 PM
I like using distilled because it eliminates the minerals that are in the tap water. Usually what I do is dump as much coolant as possible, and refill with distilled water. You can get it by the gallon for less than a dollar. Then I run it to operating temperature, shut it off, dump and refill again with distilled. I do this until the coolant I'm draining is essentially clear, maybe 8-10 gallons. After the last dump, fill with straight anti-freeze first, to bring concentration up. (you wouldn't be able to get enough of the 50/50 mix stuff in to overcome the straight water, plus I don't know if the mix is created with distilled water) Don't forget to flush out and refill the overflow with fresh coolant and distilled too.

outsider
03-30-11, 03:00 PM
Thanks for the tips!

jayoldschool
03-30-11, 06:31 PM
Don't open the petcock. They can crack the rad. Just pull the lower hose off, and let it all drain into a big bucket.

sven914
03-30-11, 09:10 PM
Anyways, I will do this block flush before I start replacing parts. BTW, where is the temp sensor located? I have the FSM at home but I am not at home. If you don't know off the top of your head that's ok, I can check the FSM when I do go home. Thanks ;)

It's on the top, driver's side front corner. Here is a picture I took of it when I made it obsolete:

http://carphotos.cardomain.com/ride_images/3/2503/2881/31256440118_large.jpg

outsider
03-30-11, 09:36 PM
with the green wire?

sven914
03-31-11, 03:52 PM
Yeah