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Stavesacre21
04-27-2005, 08:18 AM
Hey peeps! Gettin ready to flush my coolant and filler' up with some new. Any help on the issue? Tough to do? Time heavy? Anyone out there actaully do this every 30K miles like the manual states? :rolleyes:

Oh yea, and does anyone have any idea how many gallons of anti-freeze it'll take to completely drain and fill up our 4.6L in the 96-98?

Today I'm also gonna be changin out the fuel filter as well, so it's gonna be a day of low key maintence around here anyway...just gettin her all set for the summer :D

Lemme know yur thoughts on any and everything :thumbsup:

Thanx!

bolt-on
04-27-2005, 12:22 PM
The biggest problem with the modular engines when refilling coolant is getting the air out of the system. From the 1997 SVT Mustang Cobra Owner Guide Supplement (in case you do not have one):

1. Remove coolant reservoir pressure cap.
2. Remove engine coolant outlet tube fill plug on the engine (located in
front of the alternator).
3. Add a 50/50 mixture of recommended cooling system fluid and water to
coolant outlet tube fill neck until the reservoir is full.
4. Reinstall the pressure cap to the coolant reservoir.
5. Continue filling at the engine coolant fill neck slowly while allowing air
escape.
6. Reinstall engine coolant tube fill plug when system is full (new O ring?).
7. Select maximum heater temperature and fan speed settings. Position
control to discharge air at A/C vents in instrument panel.
8. Start engine and allow to idle. While engine is idling, feel for hot air at
A/C vents. NOTE: If air discharge remains cool and engine temperature
guage does not move, shut engine off immediately. This is an indication
of low coolant level and/or air pockets in coolant system. Allow engine to
cool and repeat previous steps.
9. Allow engine to idle until normal operating temperature is reached. . . .
lower radiator hose should feel hot to the touch.
10.Shut off the engine. After the engine cools down, recheck the engine
coolant level. Fill reservoir to the COLD-FULL level. . . . Check for leaks.
11.Recheck engine coolant level . . . . after one or two occasions of full
vehicle use.

Cooling system refill capacity is 14.1 quarts, but you will likely not get that much in unless both block drain plugs are removed while draining the system. One of the drain plugs is behind a motor mount and no tool I own will reach it. If this sounds like a PIA, take heart; the procedure is even worse on my 1997 GT!

Mileage changes are not relevant on my cars as annual mileage is low. I change coolant every two years since corrosion is the enemy.

Stavesacre21
04-27-2005, 04:07 PM
Thanx for the heads up. Im still not really sure if i even wanna get involved with all of that, so i just might have a dealer end up changin it all out...who knows :rolleyes:

Thanx for the advice though! :)

crutch95
04-27-2005, 07:25 PM
I seem to change my about evey 10,000 mile b/c im having to put a new motor in. But i have all that fixed now and it it running great i would do it every 30,000 miles or so it can not heart.

ausie
04-30-2005, 11:49 AM
Unwritten intervals: Coolant every 24k miles, fuel filter every 16k miles.

If you are going through the procedure of changing the coolant, you may as well replace the thermostat and O ring at the same time. Thermostats do not last that as long as you think they do. Besides that they are not that difficult to replace.

BTW, where are the coolant plugs on the block located? I only used the thermostat dump method since I replace the thermostat when I change the coolant (lowest part of the cooling system).

dewone
05-03-2005, 08:02 AM
On the thermostat. You can do a quick check by suspending it in boiling water with a thermometer. When it reaches temp you can watch it open. If it doesn't replace. No biggy

bolt-on
05-04-2005, 07:01 PM
BTW, where are the coolant plugs on the block located? I only used the thermostat dump method since I replace the thermostat when I change the coolant (lowest part of the cooling system).

One on each side of engine block. These are 3/8-18 pipe plugs. The left side drain plug is very difficult to access under the motor mount. Also while draining coolant, remove the heater hoses and drain coolant from heater core by blowing 10 psi compressed air into the heater core.

SuperG
10-31-2006, 07:08 AM
Do any of you perform a cleaning flush? If so, what do you use and what's the procedure?

SNAKEYE
10-31-2006, 12:57 PM
Do any of you perform a cleaning flush? If so, what do you use and what's the procedure?
Yes, but not as yet on SNAKEYE.

Prestone Super Flush. Follow label directions, which basically consist of: drain and properly discard present coolant, fill system with water topping up and adding flush thru the crossover tube plug, idle engine up to operating temperature plus 15 minutes, let engine cool, drain, re-fill with rinse water only (top up thru crossover tube), let engine idle to operating temperature plus 15 minutes, let cool, drain, fill with 50/50 coolant (top up thru crossover tube plug).

The cool-down sessions can be time consuming. Try something like a 20" window fan to blow ambient air thru the radiator/engine compartment to speed up the process. Be careful when removing the expansion tank cap.
Personally, I use hot water for the rinse and final fill-ups just to avoid any possibility of cooling down a relatively hot engine with relatively cold water.

SuperG
10-31-2006, 01:54 PM
At least it's a simple process! Thanks!

SuperG
11-01-2006, 07:23 AM
BTW, how does one properly discard coolant? Does a place like AZ take it?

blk04cobra1
11-01-2006, 08:47 AM
BTW, how does one properly discard coolant? Does a place like AZ take it?
they should, bring it with you and tell them you need to recycle some fluid...we've taken oil and coolant to Advance Auto...