Coolant Change Guru's, Questions
Thread Starter
Instructor
Joined: Jun 2001
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From: Coronado CA
Coolant Change Guru's, Questions
When following the Service Manual for coolant change there is no mention of turning on the heater. Should heater be off?
Also, the "reving" from idle to 3000 rpm at 30 second intervals, is this a quick rev to 3000 and back to idle ever 30 seconds or increasing rpm from idle slowly to 3000 and slowly back to idle over a 30 second period?
If system holds 3.15 gallon (12.4 quarts) how much can you really get out with the drain?
Just want to do it correctly with no air in the system.
Thanks for any guidance.
Also, the "reving" from idle to 3000 rpm at 30 second intervals, is this a quick rev to 3000 and back to idle ever 30 seconds or increasing rpm from idle slowly to 3000 and slowly back to idle over a 30 second period?
If system holds 3.15 gallon (12.4 quarts) how much can you really get out with the drain?
Just want to do it correctly with no air in the system.
Thanks for any guidance.
Team Owner
Joined: Sep 2001
Posts: 23,283
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From: Lake Elsinore, CA
Re: Coolant Change Guru's, Questions (CarlB)
Hold it steady at 3000 for 30 secs and let it idle steadily for 30 secs alternately until it hits about 210 deg. F. The heater should be off. I've had to drain mine several times and you never get a full system drain. Most I've gotten is a couple of gallons.
In fact, I just refilled mine this weekend using the service manual procedure and it worked perfectly. :cheers:
[Modified by Patches, 10:11 AM 12/16/2002]
In fact, I just refilled mine this weekend using the service manual procedure and it worked perfectly. :cheers:
[Modified by Patches, 10:11 AM 12/16/2002]
Le Mans Master
Joined: Oct 2000
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From: Sausalito CA
Re: Coolant Change Guru's, Questions (CarlB)
Good morning CarlB,
I agree with you about the heater question.
I think it should be on....even though the manual does not mention it.
Nice insight.
I agree with you about the heater question.
I think it should be on....even though the manual does not mention it.
Nice insight.
Team Owner
Joined: Sep 2001
Posts: 23,283
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From: Lake Elsinore, CA
Re: Coolant Change Guru's, Questions (Kenny94945)
Why introduce air into the filled heater core? The procedure is designed to purge air from the "open" part of the system where air has entered during a normal drain. If you turn the heater on, air that is in the main system will be introduced into the heater core and need to be purged from there as well.
Now, if you're doing a system flush, then I would definitely run the heater to purge the old coolant. :yesnod:
Now, if you're doing a system flush, then I would definitely run the heater to purge the old coolant. :yesnod:
Thread Starter
Instructor
Joined: Jun 2001
Posts: 147
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From: Coronado CA
Re: Coolant Change Guru's, Questions (Patches)
Patches & Kenny94945,
Thanks for the quick replies, but now I confused. If you are changing coolant wouldn't you want to change all of it possible, i.e. have the heater on just as you would to flush the system? How do you purge the air from the heater core?
Another question, did you start the procedure with the car up to temperature, seems if you need to hold the rpm at 3000 for 30 seconds the block should have temperature?
Thanks again,
CarlB
Thanks for the quick replies, but now I confused. If you are changing coolant wouldn't you want to change all of it possible, i.e. have the heater on just as you would to flush the system? How do you purge the air from the heater core?
Another question, did you start the procedure with the car up to temperature, seems if you need to hold the rpm at 3000 for 30 seconds the block should have temperature?
Thanks again,
CarlB
Team Owner
Joined: Sep 2001
Posts: 23,283
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From: Lake Elsinore, CA
Re: Coolant Change Guru's, Questions (CarlB)
If you are changing the fluid then, yes, you'll want to run the heater, as I indicated above.
The service manual procedure is geared towards a refill after service work requiring a radiator drain. This is what I did for my h/c job. Since I was just refilling the emptied portion of the system, I followed the manual's steps.
For a total flush, all the fluid needs to be replaced and that includes the heater core. So, yes, the heater needs to be flushed along with the rest of the system in this case. The air will be purged in the core along with the rest of the system as the fluid pushes air out during the cycling process.
I let the car warm up to the point where I felt comfortable revving to 3K before I started the procedure. All air appeared to be gone as the system is functioning perfectly.
The service manual procedure is geared towards a refill after service work requiring a radiator drain. This is what I did for my h/c job. Since I was just refilling the emptied portion of the system, I followed the manual's steps.
For a total flush, all the fluid needs to be replaced and that includes the heater core. So, yes, the heater needs to be flushed along with the rest of the system in this case. The air will be purged in the core along with the rest of the system as the fluid pushes air out during the cycling process.
I let the car warm up to the point where I felt comfortable revving to 3K before I started the procedure. All air appeared to be gone as the system is functioning perfectly.
Thread Starter
Instructor
Joined: Jun 2001
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From: Coronado CA
Re: Coolant Change Guru's, Questions (Patches)
Patches,
Thanks for the info and your patience with my questions. I will proceed. As you have said in posts before "it's all in the details".
Happy Holidays [IMG][/IMG] :seeya
Thanks for the info and your patience with my questions. I will proceed. As you have said in posts before "it's all in the details".
Happy Holidays [IMG][/IMG] :seeya
