Flushing (not just filling) coolant

Its a royal pain. There are a myriad of tubes in the car that retain coolant, even after you've drained the radiator and the engine block. Coolant 'hides' in the heater radiators, the tubes that connect them with the main return-line at the front of the car, there's the coolant tube on the side of the engine block that routes coolant behind your fuel tank to supply your heating system, there's coolant stashed at the water pump area, etc. etc. etc. Its near-impossible to get it all 'out' without dismantling stuff.

 

You are probably going to be ok with the small residual amount of old coolant in the system IF you stay on schedule flushing the system every year. It is a relatively small percentage of coolant.

Just don't forget to use only distilled water, not tap water. corrosion can do very expensive damage - very.

hth,
chris

Any other tips for reducing corrosion???

 

Dittoes on using distilled water. I have a lab distiller (Durastill - 25 years old and still working well, after a couple of rebuilds) or you can buy it at the grocers. Be sure it is DISTILLED, not de-mineralized or filtered, etc.

15 or 20 years ago Tony Palladino was selling a sacrificial anode which screwed into the block drain hole, replacing the plain bolt. I installed one and it seems to be doing its job. You can also go to a marine supply store and buy a sacrificial anode and suspend it in the coolant recovery tank - just make sure it is grounded to a good engine ground.

I drain the system, refill with distilled water, run the engine for 10 minutes after the thermostat opens (with the heater temp control on High). Let it cool, drain again, then fill with a 50/50 mix of PEAK and distilled water. I've never had a problem.

 

Let me use this thread to ask a few stupid questions:

1. Where is the block drain?

2. Where do you refill?

3. Do you remove one of the small hoses under the front underside cover (just under steering rack) to drain?

4. There is a large galvanized looking bolt screwed in to what looks like a metal coolant hose in the middle of my car. Is this a possible drain point too?


thanks

 

On your point #4, I think the plug you are looking at is the fuel tank crossover pipe drain - not for a coolant change.

 

Got under the car today for a closer look and you are right.

Thank you.

 

The other year I replaced the coolant hoses and since there is no single low-point drain for the system (but I guess the block drain is pretty low) there will be a little coolant left over in all the bends and twists. I change the coolant every year and what I do is: open the heater valves to full, open the bleed screws on the thermostat housing and radiator, remove the cap on the expansion tank and then disconnect the small heater valve return line that ties into the lower line from the radiator, and let it all drain out. The first time I did it I used the drain plug on the radiator and fluid spilled onto the lower plate of the front spoiler and then all over the place. By draining from the heater/lower radiator line it's easier to control where all the coolant goes, (into the bucket and not all over the floor) I still put down about a weeks worth of newspaper on the floor because some still spills out. I don't mess with the block plug. I think the system holds about 6 gallons and when I change it this way, I end up refilling with about 5. So 1 gallon of the old stuff stays in the system, since I change it every year, I don't think it's a big deal. If this is the first time you are doing this, it's a good idea to check the aluminum coolant pipe on the passanger side of the engine (right side looking forward) as this pipe can rub against the fuel tank and start to leak. Mine had a worn spot that I had to built up with some welding bead. I refill via the expansion tank. Fill until coolant leaks from the radiator bleed screw, close the screw and start the engine. See if any air/liquid comes out of the thermostat and then close that. As the liquid in the expansion tanks goes down, keep adding, at some point the liquid will stop dropping. Replace the cap and go for a quick drive. Park on an incline if possible with the front of the car up, and bleed the radiator again with the car running. Wear a glove as the bleed screw will be hot. Add coolant as necessary. I rebleed the radiator a couple of times over the course of a week, and have had no problems at all. Good luck.

 

For many years I worked for a chemical company where corrosion was paramount. Two of my long time colleagues were metallurgists whose raison d etre was to determine how long a piece of equipment would last in a corrosive atmosphere. I asked each of them whether sacrificial anodes work (hoping I be able to lessen coolant changes). The answer was that it might only work in the vicinity where it is located. Their opinion was based on years of exeperience in the chemical industry and both hold graduate level degrees from excellent schools. They know what they are talking about.

Furthermore, I have owned several vehicles for over 20 years each. I just drain the block and the radiator and be done with it. I think draining every last bit of coolant is unecessary and I especially don't like to remove radiator hoses from old radiators. I have never had a corrosion problem. I change coolant every 2-3 years.

 

Not on the lower left - driver's side? Wonder why.... That's where it is on my '87.

 

I have an '89 and flushed it the way Carl Rose did: at the small heater hose at the front, it was pretty simple and fast. I used Prestone undiluted extended-life coolant and then mixed it with distill water. I've just bought couple gallons last week, they're kind of greenish yellow.

 

try Summit or Jegs? maybe they can help you.

 

Not to keep beating a dead horse but if one is present it should be about 2 feet left of the temperature sensor you mention. It's a black 13mm hex and is hard to see because it's the same color as the radiator. I have to use a light to see it even with my car on a lift.

 

peak coolant is green and should be compatable with our system.
you want the original mix, not the new blends.advanced auto sells it.

i believe that babe (what's her name?) is sponsared by it.

 

this even makes it easier
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