Hello 6 speeders I decided to change the coolant in my 05 DB9 and figured this was a good time to document it. I haven't noticed any threads regarding this procedure so this might help some of you do-it-yourselfers. Just a little about myself -- I'm not an Aston Martin mechanic by any means, just a hobbyist that enjoys working on his own cars, so with that being said I take no responsibility for any damage that occurs if you decide to follow my instructions below on your own car.

I was told the coolant capacity for a DB9 is around 4 gallons. If you decide to follow this method you will remove about 75% (3 gallons) of the old coolant. If you want to remove all of the coolant just follow these instructions twice for a full flush, making sure to drive the car at least 1/2 hour before the second flush.

Tools Required:

-Torx T30 bit for belly pan.
-Large phillips or flat head screw driver for radiator drain plug.
-Garage lift or hydraulic jack and jack stands

Fluids Required: I used "Prestone Dex-Cool Extended Life" antifreeze with distilled water (50/50 mix). Dex-Cool extended life is a Havoline OAT equivalent antifreeze that our cars require.





Note: Never open the coolant reservoir cap on a hot engine!

Step 1: Remove coolant reservoir cap (cold engine).





Step 2: Raise vehicle to desired height that is comfortable for you -- make sure you have enough room to comfortably remove the belly pan.





Step 3: Remove the T30 torx bots that secure the belly pan. I started at the front of the car and worked my way back. If you decide to use this method, the front bumper lip keeps the belly pan secure while working your way towards the back of the car. While working the final bolt out make sure to support the belly pan until you ready to slide it back and out from under the car.





Step 4: Once the belly pan is removed its time to remove the radiator drain plug located on the passenger side of the radiator. Warning, this will be messy! Once you have the drain plug loose and flopping around give it a tug to pull it out. After about 5 minutes all the coolant should be out (about 3 gallons). Re-install the drain plug and lower the car.





Step 5: Now that the car is lowered and on level ground its time to start filling the reservoir with coolant. I used a 50/50 ratio of coolant to distilled water. Once the coolant reservoir is full its time to start the car.





Step 6: Start the car and turn the heat to max. As the car is running monitor the coolant reservoir level and add as needed. I let the car idle for about 10 mins and watched the system burp air. As the car was running I also squeezed both coolant hoses on the front of the engine a few times to help accelerate the bleeding. As the temp needle nears the middle mark you should start to feel nice warm heat coming out of the vents. If you don't feel warm air, bring the car to a fast idle (2000 RPMs) for about 30 seconds and let off and repeat until you do -- this will help accelerate the bleed time. While all of this is going on be sure to monitor both the temp needle and coolant reservoir. If for any reason the temp needle goes above the middle mark shut the car off and check for leaks and coolant level. note: mine took almost 3 gallons of coolant to fill and burp.

Step 7: If you are reading this step that means you have nice warm heat and the coolant reservoir level is holding steady. Now is the time to screw on the coolant reservoir cap and let the system build pressure (car still running). After about 5-10 minutes of the car running check to see if any coolant leaks are present. If no leaks are present take the car for a short drive, then return and shut the car off to let cool.

Step 8: After the car has cooled from the short drive you can remove the coolant reservoir cap and check the level. If level is low add coolant and repeat step 7.

Step 9: At this step you have burped the system and the coolant reservoir level is holding steady after a test drive. All that's left is to re-install the belly pan and monitor the coolant level for the next few days. Since this process only removes 75% of the coolant you can drive the car for about 30 mins to an hour and do a drain refill again if you so desire.

Now bask in the satisfaction that you did the job yourself while also saving about $1k.

 

Thanks dan87951- really great instructional post. Photo's are always a plus! Post like your are the real benefit to the forum.......and about you 4 post lift, very nice. I wish I had the head room. Thanks again!!

 

Excellent Dan, addedto faq!

 

No problem guys always happy to help! On a scale of 1-10, 10 being the most difficult I would put this at a 3.5-4. To put that in perspective an oil change would rate between a 2-2.5 because of the location of the oil filter. Hopefully, this helps someone decide if they want to try and tackle this job themselves.

 

Excellent work Dan.
Can you please explain what we are looking at in pic # 4 (not counting preston coolant can)?


Also to clarify-its ok to keep the car running with coolant cap open in step 6 right?


do you premix coolant and distill water at 50/50?

 

Thanks!

Picture 4 shows you the location of the drain plug on the radiator -- large phillips or flat head screw driver is needed.

Yes, you will need to leave the coolant cap off until the air is out of the system. The coolant cap should remain off until you reach step 7 in my instructions. Never go above a fast idle while the coolant cap is removed. Hope this helps!

Yes, mix 50/50 coolant to distilled water.

 

thanks Dan I did my Vantage V8 this week but i missed the step with turning up the cabin heat??? I have driven it after fitting enron 50% /50% water distilled
car has not over heated and did not take much top up, I only managed to drain out about 7 litres from the 12 litre system?? I report that after 28 000Km the water that came out was clean and pink and i was almost thinking it was not nessasary to do a rad flush?? but am very rigid with maintenance. (book says every 4 years)

what is this OAT stuff you guys refer too??its in the manual as well but i have no idea what it is i hope that what i have put in will not compromise my seals or hoses now?

 

Hi Greg, it's important you turn on the heat that way the heater core can be bleed as well. I don't know what "enron" is but my car (DB9) requires OAT coolant (Dex-Cool). It's very important that you do NOT mix coolant types this can cause a chemical reaction to occur which could lead to gelling. The only way to do a proper coolant change is to drain as much of the coolant as you can from the system, including the radiator. Without draining the radiator you will not get very much coolant out.

OAT is a type of coolant which stands for Organic Acid Technology. It's an extended life coolant that lots of car companies use now a days. You can read more about it by doing a google search. I decided to use Prestone Dex-Cool which is a OAT coolant that is readily available at most supermarkets.

I don't know what coolant you topped up with but if your Vantage requires OAT coolant do a complete drain of the old stuff and refill with OAT coolant.

 

can please someone tell me where is the draqin plug for 2009 DB9? located
Thankx

 

It doesn't have one. Hose removal to drain.

 

It does have it
We figured it out after 30 min of picking around
My friend Tookthe pictures he will post it later
It's in similar location but it's not Phillips head and it turns only 90 degree and pulls out

 

Wildcat and I changed our coolant yesterday. My car is a 2005, and the drain valve was the same as illustrated in Step 4 above. On my car, just loosening the valve lets the coolant out at a very fast rate. I didn't have to remove the valve. When you do this, make sure the coolant isn't hot and wear a raincoat

The 2009 car had a different style valve as illustrated. Normally, the ridge in the valve is horizontal indicating that it is in the closed position. To open it, turn it ninety degrees to the vertical position, then find a pliers or other tool that will grip the ridge and pull it out. It takes a strong tug to get it open. The flow rate through this type valve is much slower than the rate with the phillips style drain, so plan on allowing some time for the system to empty.

 

90 degrees counterclockwise, clockwise, or does it matter?

 

This one was CCW. It should only turn in one direction.

 

I have the belly pan off on my '07 and can't see anything that looks like a drain valve.

Does the wheel liner or the pan under the radiator have to come off?