replacing coolant

Post by **januwan** » 04 Sep 2010, 12:20

Will draining trough the plastic valve get rid of all coolant or do I have to disconnect other hoses.
When adding new coolant do you mix it before or just add coolant and then distilled water to the holding tank (reservoir)
Appreciate any guidance

Post by **jmmxc** » 04 Sep 2010, 13:05

I use Prestone 50/50. The dude at Volvo told me that is what is commonly used. It is already mixed.
To get rid of most coolant from the engine I just did it this morning as follows:
(a) Open up expansion tank.
(b) Open the the radiator valve (on driver side). Be careful this piece is plastic and can be brittle. It breaks easily. Or you may have to replace rubber O rings if they are cracked. You will get a large volume of the coolant out this way. Use a large bucket to catch the coolant.IF you want to get rid of all coolant, then....
(c) Open the bottom radiator hose to drain more sitting coolant on the back side of the engine block. (Loosen the hose clamp and pull it out...........you will have coolant coming your way, be prepared. Let the coolant drain (in a big pan)
Now put back and tighten the hose in place, close the radiator valve carefully.
Pour into the expansion tank the replacement coolant.
Pour it slowly to prevent air being trapped in the system. When filled, make sure there is no leak under the car....and start engine for a few minutes. Add additional coolant as the trapped air will come out. Let the car sit for a while and check level again.
(Note: Jack up the care, and Do use jack stands to stabilze the car frame. A pair of gogle is essential, you cannot be too careful)
Also you can do a search on this site for additional info on the subject.
I hope this will help.
jmmxc

Post by **j_cd** » 04 Sep 2010, 15:06

I recommend Zerex G-05. Carquest carries it. Pre mix with 1/2 distilled water. There will be a little bit of coolant left in some of the hoses, but it's not a significant amount.

Post by **JDS60R** » 04 Sep 2010, 16:05

Unless you drain the heater core and disassemble the motor you will only get 6 of 9 quarts out.

I suggest Volvo antifreeze and distilled water. There are many posts here on the subject so please search the topic.

Here are some facts.
Prestone does not contain 2 important ingredients (sebacic acid and a low level of silicates) that the Volvo coolant has and therefore is considered an OAT coolant. Volvo is a HOAT. HOAT's are used in diesels and turbo applications as it is better at controlling localized boiling.

G-05 is a good HOAT and closer to the Volvo coolant but not chemically the same.
BMW blue coolant is the same as Volvo.
Mercedes is different than Volvo and BMW

The last 17 years dealing with Volvo's has revealed this:
If you have a non turbo or do not drive hard or in a hot climate you can get away with Prestone. If you have a turbo I strongly suggest a HOAT. Pressure caps and thermostats should also be replaced when you have access to them.(like now)

Local dealers here also say Prestone is fine. They also had no idea what sebacic acid was or the benefits of a HOAT. Your manual will tell you that Volvo antifreeze is required. You also don't have to worry about mixing a HOAT and an OAT which can cause issues.

A gallon of Prestone is about $10. A gallon of Volvo is $20 with discount or $24 normal. Don't risk anything for $14. Especially damage to your motor.

bw77 · Post by **bw77** » 04 Sep 2010, 18:14

I have always wondered why the Volvo owner's guide for my 99 S70GLT says that coolant does NOT normally need to be changed, and in the maintenance schedule, coolant change is NOT listed. Dealer told me they change it every 60K miles.

Post by **januwan** » 04 Sep 2010, 18:33

I used Volvo coolant , only few $ more.... but now I have a bigger problem.
This is what I did. First I did not follow jmmxc advice.
I drained 1 gallon through plastic valve on passenger side. I add 1 gallon distilled water to flush the system. I started engine and waited till thermostat opened. ( I replaced thermostat also) . Thermostat opened as expected and after some time I shut off the engine. I inspected the car for leaks and to my surprise I found leak on the passenger side. It is not under the expansion tank, it is not around the thermostat, it is not around the plastic valve. It looks it is around water pump.
Again I drained through the plastic valve a gallon of coolant mixed with water. I add 50/50 mixture of Volvo coolant and distilled water. I took the car for a ride but returned very fast because the red light (low coolant level turned up).
Where is the leak? I will look tomorrow around water pump but if you have any suggestion please let me know.

Post by **JDS60R** » 04 Sep 2010, 19:32

Here is your cooling system.
On the passenger side you have the res bottle to water pump hose, the water pump, the thermostat housing and the rear coolant pipe "7"

It sounds like you looked at the places you worked on. Sounds like tomorrows visual check will help you out.
Please let us know what you found.

Post by **JDS60R** » 04 Sep 2010, 19:59

I have always wondered why the Volvo owner's guide for my 99 S70GLT says that coolant does NOT normally need to be changed, and in the maintenance schedule, coolant change is NOT listed. Dealer told me they change it every 60K miles.

This is a good question and deserves an answer.

The type of long life coolant that Volvo uses has a long life component as well as one that depletes itself. The 2-EHA and glycol in the coolant are stable and will last for a very long time. There are lots of fleet car studies proving the longevity of these components (Ethylene glycol and 2-EHA). The low levels of silicate in the Volvo coolant work to repair the wall damage each time a bubble pops and leaves a micro scar. The silicate bonds in that spot repairing the effect. Localized boiling is what causes these bubbles and it occurs in the top 1 inch of the cylinder as that is where the heat is. As the damage occurs the silicates will be used up and then the metal is at risk. This is the main reason to stay away from a coolant without low levels of silicate in it -especially for a hard driving turbo car.
Sebacic acid also depletes but I do not have enough data to give you a proper answer.

The reason that car companies are saying you do not need to change many of these fluids ever is the cost of ownership cost ratings that many people mistakenly rely on. If you don't have to flush this or change that - it makes the cars overall ownership appear cheaper.

I wish they had a cost of ownership for people like me who want every fluid in the car to be in the top 10% of its performance range at all times. I also wish that Volvo's fluids were better. Their coolant is good - its made in New Jersey. I have issues with their gear and transmission fluids. They are on par or better then many competitors but the fluid is not up to its job. Not sure if the engineers or the fluid manufacturer are at fault here.

Many people have come to me with shift performance and gear issues int he first 60 K of ownership (the first 15 on transmissions). they get tired of taking it back in for warranty work to have it be a problem again 5-10K down the line. or they say its better but still not right. It is wonderful to be able to satisfy people with a high quality fluid change. Its easy but I don't make as much money as replacing a trans or angle gear. I am seeing quality synthetic transmission fluid still red and working well after 50K of use while the Volvo fluid is burnt at 15-30K.

As the fluids are the only lubricant and heat transfer fluids you have, I suggest you change them often and with high quality full synthetics. Except of the Haldex modules who need a semi synth by design.

The dealership recommends the fluid change at 60K because it makes them a little money and the car needs it. They are trying to build a relationship. Using top quality synths will help you use that relationship less often.

Make sure to change your radiator pressure cap and thermostat as well.

Post by **jmmxc** » 05 Sep 2010, 07:00

I do not want to change the focus of this post from the orginal issues that januwan is dealing with. But I would like to make some relevant comments about the coolant replacement situation. Based on the facts that you bring here, using Prestone 50/50 may not be a good thing for the engine in the long run and depending where you live. I would guess that leaving in the northeast where my driving is moderate using Prestone should not be that bad. I have not had any coolant related issues like leaks so far, after 150K. But there is still time for something to happen...
There is as much confusion about coolant fluid as there is for transmission fluid. Other places I read that it is not good (at all) to mix OAT and HOAT. Prestone made some claims (that were challenged) that their product is compatible to all other coolant technologies. And most (non expert) mechanics do not seem to understand and tend to confuse the different technologies with the different dye colors added to these products.
Having said that: Do you think it is a good idea to flush a system to get rid of non OAT product (the prestone 50/50) and use something like Zerex G-05? (It is somewhat not easy to find?)
In what proportion that distilled water and the coolant have to be used. My understand was that the label "50/50" meant you do not have to worry about the mix and it was all ready to use.
And one last point: I sometimes hear mechanics at reputable places recommend not to flush the system if the car has lots of mileage for fear it might develop some leaks. Is there any truth to that or are they trying to avoid post-repair liabilites?
Thanks for all the good info that is brought here.
jmmxc

bw77 · Post by **bw77** » 05 Sep 2010, 08:05

JDS60R wrote:
This is a good question and deserves an answer.

Thanks for a great answer.