Coolant system flushing procedure

[WARDHOG]

I was reading on this forum on how to properly flush the cooling system and was wondering what damage would be caused if air was trapped in the system. I'm asking this because about a year and a half ago, my coolant tank cap became defective and I lost all my coolant. The dealer in the state where I was at the this happened put some coolant in the system and I was on my way. He did not vacuum the system but let the car take the coolant in as you would on a regular automobile. Now, I want to make sure the proper coolant is up to the Porsche standards as far as proper coolant mixture. The reason I'm a little concerned is because I read the procedure on this forum and I think this should be done in order to have proper corrosion protection in my coolant system. The dealer technician that fixed my car at the time seemed to be satisfied with his results by his method. Is it safe to do this method without the vacuum method? I don't think my vacuum cleaner is waterproof and the filter can't handle it either. :rolleyes:

[Loren]

I doubt you really lost all the coolant.

Depending on his method it may have worked just as well as the vacuum draw method.

When I did my 3rd radiator install I caught the coolant in a bucket and then re-used it. I lost a little and had to add a 3 or 4 quarts for the new radiator. So I added in what I could, then opened the bleed valve and ran the engine. After the car got warmed up and shut it off and waited for it to cool. Then I added more coolant (to the full level). I repeated that process a couple more times.

Then I drive the car with the bleed valve for about two weeks (don't worry about that Cup Cars do it all the time). I added a little more coolant ever few days until it stopped needing any. Since I have no overheating even at 100 degree plus temps I think there is little or no air in my engine.

So I guess the bottom line is that unless you are running hot or have to add coolant you are likely okay. All IMHO of course... :)

[evansaero]

Just did my flush on Monday...

Yes there was air in the system after I finished, which caused my coolant temp to fluctuate.

On one of my coolant line it has a clear indicator that allows you to see if air is in the system when running.

The way I fixed this problem way by opening the bleed value, then start car and warm up completely with A/C on then raise RPM's to 4 grand and hold it there for 1-2 minutes. What I saw was the coolant temp drop from the middle of 0 to the left side of 8.

I then added more coolant and repeated one more time.

Took the car on a 1 hour drive yesterday and the coolant temp was in the middle of the 8, it stayed there and did not move.

With the older coolant I defiantly noticed that the temps would move around a lot more

Edited October 25, 2006 by evansaero

[The 996 pilot]

So I've often wondered, and cannot find in the owners manual, what the replacement interval is for the coolant in a 996 [MY2006 to be exact].

What is the recommended service interval for the coolant? Is it in there for life? Some of this stuff is pretty good now, and I do all my additions with 50%/50% distilled water and Porsche antifreeze, but I would hate to get to the point where it changes color! [Motorweeks Pat Goss always says that if the fluids have changed color, they've been in their way too long.]

Edited October 26, 2006 by The 996 pilot

[Tool Pants]

There are aftermarket devices for removing air pockets. Porsche came out with their version a few years ago.

I replaced the plastic tank on my Box last year. The mechanic friend said you did not need to bleed on a Box when only the tank is replaced. Our tank is higher than a 996. Did not ask about a 996.

In the old Box shop manual you brought the car to operating temp, then reved it from time to time (with the bleed valve open), to move any air pockets to the tank and out the bleed valve. Or something like that.

The old and new shop manual methods make sense if you run a repair place. Porsche is not going to tell the mechanic to drive a customer car around on public streets to heat it up and to get any air out. They want that car sitting in the stall, at the dealership.

I did it like Loren. I lifted up on the wire bail thing and went for a 20 minute drive. Then closed the valve.

[smartrepair]

There are aftermarket devices for removing air pockets. Porsche came out with their version a few years ago.

I replaced the plastic tank on my Box last year. The mechanic friend said you did not need to bleed on a Box when only the tank is replaced. Our tank is higher than a 996. Did not ask about a 996.

In the old Box shop manual you brought the car to operating temp, then reved it from time to time (with the bleed valve open), to move any air pockets to the tank and out the bleed valve. Or something like that.

The old and new shop manual methods make sense if you run a repair place. Porsche is not going to tell the mechanic to drive a customer car around on public streets to heat it up and to get any air out. They want that car sitting in the stall, at the dealership.

I did it like Loren. I lifted up on the wire bail thing and went for a 20 minute drive. Then closed the valve.

Where is this bleed valve (or "wire bail thing")? In the coolant tank?

Regards

Kare

[Loren]

There are aftermarket devices for removing air pockets. Porsche came out with their version a few years ago.

I replaced the plastic tank on my Box last year. The mechanic friend said you did not need to bleed on a Box when only the tank is replaced. Our tank is higher than a 996. Did not ask about a 996.

In the old Box shop manual you brought the car to operating temp, then reved it from time to time (with the bleed valve open), to move any air pockets to the tank and out the bleed valve. Or something like that.

The old and new shop manual methods make sense if you run a repair place. Porsche is not going to tell the mechanic to drive a customer car around on public streets to heat it up and to get any air out. They want that car sitting in the stall, at the dealership.

I did it like Loren. I lifted up on the wire bail thing and went for a 20 minute drive. Then closed the valve.

Where is this bleed valve (or "wire bail thing")? In the coolant tank?

Regards

Kare

Right next to the blue cap.

[mp911]

There are aftermarket devices for removing air pockets. Porsche came out with their version a few years ago.

I replaced the plastic tank on my Box last year. The mechanic friend said you did not need to bleed on a Box when only the tank is replaced. Our tank is higher than a 996. Did not ask about a 996.

In the old Box shop manual you brought the car to operating temp, then reved it from time to time (with the bleed valve open), to move any air pockets to the tank and out the bleed valve. Or something like that.

The old and new shop manual methods make sense if you run a repair place. Porsche is not going to tell the mechanic to drive a customer car around on public streets to heat it up and to get any air out. They want that car sitting in the stall, at the dealership.

I did it like Loren. I lifted up on the wire bail thing and went for a 20 minute drive. Then closed the valve.

Where is this bleed valve (or "wire bail thing")? In the coolant tank?

Regards

Kare

Right next to the blue cap.

Can someone explain how this valve works and why? On my car (2001 C2), when the engine is cold, moving the wire handle (bail thing) from horizontal to vertical will move the velve stem up to open (I assume). But when my engine is hot, the valve stem is up and moving the bail thing will make no difference.