Coolant change experience - this Bud's on me!
09-05-2001, 10:57 AM
#1
Guest
Posts: n/a
Hi all;
In the spirit of Daniel's firm belief about not doing all the drinking but rather buying a round now and then, I thought I would pass on the experience I gathered changing my own coolant. It was basically gleaned from my FSM, owners manual, this board, and several Nissan mechanics. Here is how I precisely did the job. It worked fairly well I thought.
1) Turn on ignition switch to 3 position and auto AC to 85 degrees and ECON. Wait a few seconds and shut off ignition. With engine cold, open phillips head drain plug of radiator underneath drivers side. Make sure you don't lose the rubber gasket. There is a access hole to get at it. Get your catch pan ready for action.
2) Open radiator cap and allow all of fluid to drain. There will be about 1.5 gallons discharged.
3) I prefer distilled water in my radiatior for this part unless you know the quality of your city water. Distilled water contains no minerals which may cause sedimentation. Loosely install drain plug again and fill up radiator slowly (to prevent air pockets) with the water. Re-open drain plug and allow to flush out. I repeated this one more time or untill water runs clear. Note, I did not turn on the engine to allow the water to circulate since I knew my previous coolant to be of fairly good quality. Also, it extends the time to do this job - waiting for the engine to cool down again to safely open the radiator cap. Also, I did not mess with the drain blocks again for the same reasons of coolant quality and the problem people on this board have had with these drain block plugs. Re-tighten drain plug on radiator.
4) Remove two screws from reservoir, discard old coolant, rinse with plenty of water.
5) Using a jug of Nissan coolant (about $12), pour into a clean bucket. I used the Nissan brand since it advertises no silicates etc. Add one gallon of distilled water and mix. Use a funnel to add to the radiator and again add it very SLOWLY. This seemed to be the key to avoid air pockets just like the picture shows in the FSM. In fact, I noted that when I flushed the radiator in step 3 above and added the water quickly, it took less than 1 gallon to fill it on account of the creation of air pockets. I did the final coolant fill painfully slowly adding only a dribble at a time and waiting a few secs in between. Don't forget to fill the reservoir to max line.
6) For this part, the owners manual and FSM says to leave radiator cap off but the Nissan coolant jug and several Nissan mechanics said to leave it off - so I did. Start engine and watch the temp gauge and coolant level like a hawk. Add coolant through your funnel as required. Eventually, the thermostat will apparently open and coolant will flow through the radiator. You can see this flow through the neck. Safety glasses here aren't a bad idea. Once the radiator fans turn on, you know things are really flowing so keep adding coolant as required and watch the temp gauge. Once the fans turned on, I noticed the bottom radiator hose finally warmed up - I guess because of the flow direction and thermostat/water pump considerations. I also made sure the blower fans indicated two or three "blades" to insure flow through the heater core.
7) Immediately after fans go on, as specified in the owners manual, rev the engine a few times. You will see some fluid spurt out of the radiator neck as any air pockets are apparently forced out of the system - this is what I liked about leaving the cap off for the job. I lined the radiator top with some rags to keep the job neat but don't let them fall into the fans! I tucked them all around the top to absorb the fluid. Of course, you can just rinse the whole thing after it is all done.
8) Shut off engine and after completely cool, re-check radiator level and reservoir. Top off as required. I also checked it after driving around over the next day.
9) Some cities allow coolant to be disposed down a sanitary sewer. My city allows this but also has periodic "household hazardous waste collection days". I am storing the used coolant and rinse water for one of these days. Above all, don't discard in the street as animals are attracted to the sweet tasting but poisonous fluid.
10) Some ten steps programs are worse than this, right?? You're done! Congratulate yourself on a job well done and one that probably doesn't need to be done again for at least another couple of years since the Nissan coolant is long life.
In the spirit of Daniel's firm belief about not doing all the drinking but rather buying a round now and then, I thought I would pass on the experience I gathered changing my own coolant. It was basically gleaned from my FSM, owners manual, this board, and several Nissan mechanics. Here is how I precisely did the job. It worked fairly well I thought.
1) Turn on ignition switch to 3 position and auto AC to 85 degrees and ECON. Wait a few seconds and shut off ignition. With engine cold, open phillips head drain plug of radiator underneath drivers side. Make sure you don't lose the rubber gasket. There is a access hole to get at it. Get your catch pan ready for action.
2) Open radiator cap and allow all of fluid to drain. There will be about 1.5 gallons discharged.
3) I prefer distilled water in my radiatior for this part unless you know the quality of your city water. Distilled water contains no minerals which may cause sedimentation. Loosely install drain plug again and fill up radiator slowly (to prevent air pockets) with the water. Re-open drain plug and allow to flush out. I repeated this one more time or untill water runs clear. Note, I did not turn on the engine to allow the water to circulate since I knew my previous coolant to be of fairly good quality. Also, it extends the time to do this job - waiting for the engine to cool down again to safely open the radiator cap. Also, I did not mess with the drain blocks again for the same reasons of coolant quality and the problem people on this board have had with these drain block plugs. Re-tighten drain plug on radiator.
4) Remove two screws from reservoir, discard old coolant, rinse with plenty of water.
5) Using a jug of Nissan coolant (about $12), pour into a clean bucket. I used the Nissan brand since it advertises no silicates etc. Add one gallon of distilled water and mix. Use a funnel to add to the radiator and again add it very SLOWLY. This seemed to be the key to avoid air pockets just like the picture shows in the FSM. In fact, I noted that when I flushed the radiator in step 3 above and added the water quickly, it took less than 1 gallon to fill it on account of the creation of air pockets. I did the final coolant fill painfully slowly adding only a dribble at a time and waiting a few secs in between. Don't forget to fill the reservoir to max line.
6) For this part, the owners manual and FSM says to leave radiator cap off but the Nissan coolant jug and several Nissan mechanics said to leave it off - so I did. Start engine and watch the temp gauge and coolant level like a hawk. Add coolant through your funnel as required. Eventually, the thermostat will apparently open and coolant will flow through the radiator. You can see this flow through the neck. Safety glasses here aren't a bad idea. Once the radiator fans turn on, you know things are really flowing so keep adding coolant as required and watch the temp gauge. Once the fans turned on, I noticed the bottom radiator hose finally warmed up - I guess because of the flow direction and thermostat/water pump considerations. I also made sure the blower fans indicated two or three "blades" to insure flow through the heater core.
7) Immediately after fans go on, as specified in the owners manual, rev the engine a few times. You will see some fluid spurt out of the radiator neck as any air pockets are apparently forced out of the system - this is what I liked about leaving the cap off for the job. I lined the radiator top with some rags to keep the job neat but don't let them fall into the fans! I tucked them all around the top to absorb the fluid. Of course, you can just rinse the whole thing after it is all done.
8) Shut off engine and after completely cool, re-check radiator level and reservoir. Top off as required. I also checked it after driving around over the next day.
9) Some cities allow coolant to be disposed down a sanitary sewer. My city allows this but also has periodic "household hazardous waste collection days". I am storing the used coolant and rinse water for one of these days. Above all, don't discard in the street as animals are attracted to the sweet tasting but poisonous fluid.
10) Some ten steps programs are worse than this, right?? You're done! Congratulate yourself on a job well done and one that probably doesn't need to be done again for at least another couple of years since the Nissan coolant is long life.
09-05-2001, 01:16 PM
#3
Senior Member
Join Date: Aug 2000
Posts: 492
Interesting write-up. But you seem to be indicating that your method leaves over 2 qts of the old antifreeze mixture in the block since you said you didn't run the engine between the two drainings. Am I reading that correctly?
If so, having changed the OEM antifreeze at 48 months on my 96 Maxima, the time to do the job completely really was worth it to me. I drained the radiator, re-filled it with water, ran the engine, re-drained etc. 5 times before the coolant looked mostly clear. It just seems to make sense to me to do the job completely, since the 2 qts of four year old antifreeze surely isn't the quality it was when installed be Nissan.
-Mark
If so, having changed the OEM antifreeze at 48 months on my 96 Maxima, the time to do the job completely really was worth it to me. I drained the radiator, re-filled it with water, ran the engine, re-drained etc. 5 times before the coolant looked mostly clear. It just seems to make sense to me to do the job completely, since the 2 qts of four year old antifreeze surely isn't the quality it was when installed be Nissan.
-Mark
09-05-2001, 02:27 PM
#4
Senior Member
Join Date: Sep 2000
Posts: 4,601
The block drains are so difficult to reach than most people (including professional technicians) don't bother with them. Here are two popular coolant-change methods.
Method 1) When the engine is cool remove the radiator fill cap and leave it off. Open the radiator draincock and allow the coolant to drain. Refill with clean water. Run the engine until warm. Repeat this drain-fill-warmup cycle three or four times. When the draining liquid looks clear the coolant flush is complete.
Method 2) When the engine is cool remove the radiator fill cap and leave it off. Open the radiator draincock. Set a garden hose to run at "trickle" and put it in the radiator fill port. Start the engine and let it idle. The idea is to control the flow of fresh water to slightly exceed the rate of drain-out. Let the engine idle until it reaches normal operating temperature, and then another five minutes. When the draining liquid looks clear the coolant flush is complete.
Please remember that most kinds of antifreeze are toxic to animals. Hose down your work area thoroughly to avoid poisoning a loved pet.
Method 1) When the engine is cool remove the radiator fill cap and leave it off. Open the radiator draincock and allow the coolant to drain. Refill with clean water. Run the engine until warm. Repeat this drain-fill-warmup cycle three or four times. When the draining liquid looks clear the coolant flush is complete.
Method 2) When the engine is cool remove the radiator fill cap and leave it off. Open the radiator draincock. Set a garden hose to run at "trickle" and put it in the radiator fill port. Start the engine and let it idle. The idea is to control the flow of fresh water to slightly exceed the rate of drain-out. Let the engine idle until it reaches normal operating temperature, and then another five minutes. When the draining liquid looks clear the coolant flush is complete.
Please remember that most kinds of antifreeze are toxic to animals. Hose down your work area thoroughly to avoid poisoning a loved pet.
09-10-2001, 07:18 PM
#5
Guest
Posts: n/a
Mark and Daniel, thanks for the replies. Due to my schedule, sometimes I am unable to go online for several days at a time - hence the delay in my response.
Mark, you are correct that my method did in fact leave old coolant in the block. My FSM states that my 95 requires 9 3/8 qt. coolant total capacity including the reservoir. This means that without draining the block, 3 1/4 qts old coolant remain in the block based on my observation that a little over 6 qts was required between the reservoir and the radiator alone. If after filling your radiator with water you warmed up the engine to the point that the thermostat opened and water flowed full circle between the radiator and block, you would be left with nearly pure water in the block (unless the block drains were opened to then drain the water). Therefore, finally filling the radiator with a 50% mixture would eventually be diluted to about a 33% mixture once the block water and radiator coolant mixed. Although the freezing point depression and boiling point elevation does not suffer much in going from a 50% mixture to a 33% mixture, I believe a 50% mixture is better on account of a higher level of anti-corrosion inhibitors. Remember that coolant/antifreeze obtains its anti-freeze and anti-boil properties from the ethylene glycol but all the other good stuff such as corrosion inhibition relies on the additives. Therefore, according to my calculations, if one leaves water in the block after doing a complete flush, one should use a 77% mixture which will dilute itself to a perfect 50% mixture once diluted by the water in the block. One can do a final check on the coolant concentration using either the new Prestone test strips or an old-fashioned density meter. As for me, I plan on doing this frequently enough that the corrosion inhibitors are never depleted, no sedimentation will be occurring, and there is no need for me to worry about "flushing" the system. My simple "drain and refill with 50%" combined with a simple radiator rinse should be sufficient for the maintenance-minded Maxima owner.
Mark, you are correct that my method did in fact leave old coolant in the block. My FSM states that my 95 requires 9 3/8 qt. coolant total capacity including the reservoir. This means that without draining the block, 3 1/4 qts old coolant remain in the block based on my observation that a little over 6 qts was required between the reservoir and the radiator alone. If after filling your radiator with water you warmed up the engine to the point that the thermostat opened and water flowed full circle between the radiator and block, you would be left with nearly pure water in the block (unless the block drains were opened to then drain the water). Therefore, finally filling the radiator with a 50% mixture would eventually be diluted to about a 33% mixture once the block water and radiator coolant mixed. Although the freezing point depression and boiling point elevation does not suffer much in going from a 50% mixture to a 33% mixture, I believe a 50% mixture is better on account of a higher level of anti-corrosion inhibitors. Remember that coolant/antifreeze obtains its anti-freeze and anti-boil properties from the ethylene glycol but all the other good stuff such as corrosion inhibition relies on the additives. Therefore, according to my calculations, if one leaves water in the block after doing a complete flush, one should use a 77% mixture which will dilute itself to a perfect 50% mixture once diluted by the water in the block. One can do a final check on the coolant concentration using either the new Prestone test strips or an old-fashioned density meter. As for me, I plan on doing this frequently enough that the corrosion inhibitors are never depleted, no sedimentation will be occurring, and there is no need for me to worry about "flushing" the system. My simple "drain and refill with 50%" combined with a simple radiator rinse should be sufficient for the maintenance-minded Maxima owner.
09-10-2001, 08:10 PM
#6
Senior Member
Join Date: Aug 2000
Posts: 492
B.C.
Our systems may have slightly different capacities.
After achieving clear water in my cooling system, I drained the radiator again to provide room for, according to the notes I wrote in my FSM, 4Qts and 2oz of pure antifreeze and then topped up with more water for a 50/50 mix. Also filled the reservoir with 50/50 mix.
My FSM manual says my 96 Maxima has a 8-1/8 qt capacity not counting the expansion reservoir.
Leaving as much old antifreeze in the system as you did would bother me.
Our systems may have slightly different capacities.
After achieving clear water in my cooling system, I drained the radiator again to provide room for, according to the notes I wrote in my FSM, 4Qts and 2oz of pure antifreeze and then topped up with more water for a 50/50 mix. Also filled the reservoir with 50/50 mix.
My FSM manual says my 96 Maxima has a 8-1/8 qt capacity not counting the expansion reservoir.
Leaving as much old antifreeze in the system as you did would bother me.
09-11-2001, 06:58 AM
#7
$5, couple hours, and job well done
Originally posted by Daniel B. Martin
The block drains are so difficult to reach than most people (including professional technicians) don't bother with them. Here are two popular coolant-change methods.
Method 1) When the engine is cool remove the radiator fill cap and leave it off. Open the radiator draincock and allow the coolant to drain. Refill with clean water. Run the engine until warm. Repeat this drain-fill-warmup cycle three or four times. When the draining liquid looks clear the coolant flush is complete.
Method 2) When the engine is cool remove the radiator fill cap and leave it off. Open the radiator draincock. Set a garden hose to run at "trickle" and put it in the radiator fill port. Start the engine and let it idle. The idea is to control the flow of fresh water to slightly exceed the rate of drain-out. Let the engine idle until it reaches normal operating temperature, and then another five minutes. When the draining liquid looks clear the coolant flush is complete.
Please remember that most kinds of antifreeze are toxic to animals. Hose down your work area thoroughly to avoid poisoning a loved pet.
The block drains are so difficult to reach than most people (including professional technicians) don't bother with them. Here are two popular coolant-change methods.
Method 1) When the engine is cool remove the radiator fill cap and leave it off. Open the radiator draincock and allow the coolant to drain. Refill with clean water. Run the engine until warm. Repeat this drain-fill-warmup cycle three or four times. When the draining liquid looks clear the coolant flush is complete.
Method 2) When the engine is cool remove the radiator fill cap and leave it off. Open the radiator draincock. Set a garden hose to run at "trickle" and put it in the radiator fill port. Start the engine and let it idle. The idea is to control the flow of fresh water to slightly exceed the rate of drain-out. Let the engine idle until it reaches normal operating temperature, and then another five minutes. When the draining liquid looks clear the coolant flush is complete.
Please remember that most kinds of antifreeze are toxic to animals. Hose down your work area thoroughly to avoid poisoning a loved pet.
09-11-2001, 07:56 AM
#8
Guest
Posts: n/a
Mark:
Sounds like you added enough coolant then to compensate for the dilution effect of pure water in the block.
Since I did the job about two years ago and again just last week, I'm convinced the Nissan Long Life coolant I left in the block had not been depleted of its additives. "Drain and refill" is the standard approach of all the Nissan dealers in my area. Anyone trying to do a flush should just be aware that the engine must run for quite a while, not a few minutes, to allow the thermostat to fully open. It sounds like you did it correctly. Otherwise, one could mistakenly think it had been flushed when in reality, the old coolant will still remain in the block. I think we both did thorough jobs and should congratulate ourselves on being mindful of this maintenance issue.
Sounds like you added enough coolant then to compensate for the dilution effect of pure water in the block.
Since I did the job about two years ago and again just last week, I'm convinced the Nissan Long Life coolant I left in the block had not been depleted of its additives. "Drain and refill" is the standard approach of all the Nissan dealers in my area. Anyone trying to do a flush should just be aware that the engine must run for quite a while, not a few minutes, to allow the thermostat to fully open. It sounds like you did it correctly. Otherwise, one could mistakenly think it had been flushed when in reality, the old coolant will still remain in the block. I think we both did thorough jobs and should congratulate ourselves on being mindful of this maintenance issue.
Thread
Thread Starter
Forum
Replies
Last Post
hez8813
5th Generation Maxima (2000-2003)
11
03-12-2020 12:06 AM
97_GXE
4th Generation Maxima (1995-1999)
20
09-17-2015 08:12 PM
ag90fox
7th Generation Maxima (2009-2015)
6
09-09-2015 12:22 PM