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Old 05-02-2020 | 06:44 AM
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2002 496 closed system. Other than drain refill with 50/50 distilled water does system need to be bleed out and if so how?

thx
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Old 05-02-2020 | 11:25 AM
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Brass Air bleed mounted on top of thermostat housing.
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Old 05-02-2020 | 11:37 AM
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I don't remember bleeding mine. The coolant tank is the highest point on the system. Just take a gallon or two of pink with you on your first run, and top off if the reservoir goes a bit low.
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Old 05-03-2020 | 07:03 PM
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Originally Posted by PA.WOODCHUCK
2002 496 closed system. Other than drain refill with 50/50 distilled water does system need to be bleed out and if so how?

thx
525 Coolant Change

I posted the proper procedure from the 496 FSM in this thread.
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Old 05-03-2020 | 07:46 PM
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My closed coolant system (the one from CP performance) specifically called for green. Actually, I'm not sure it was in the literature, but I believe I called them and asked.

When I filled mine it was mounted to the front of the heads high enough that it took almost no antifreeze to top off, but there wasn't anything on bleeding it.
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Old 05-04-2020 | 10:23 PM
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use dex cool then mix 50 to 50 with DISTILLED WATER. the slower you poor in the coolant the less air in the system. - leave cap off for an hour or 2 - go eat comeback check level. Add more if needed.
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Old 05-05-2020 | 11:56 AM
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Originally Posted by BUP
use dex cool then mix 50 to 50 with DISTILLED WATER. the slower you poor in the coolant the less air in the system. - leave cap off for an hour or 2 - go eat comeback check level. Add more if needed.
John - should I not be using the green stuff? Did I get that wrong?

Merlin blocks 565, aluminum heads, CP performance half/system.....
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Old 05-05-2020 | 12:24 PM
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Originally Posted by seafordguy
John - should I not be using the green stuff? Did I get that wrong?

Merlin blocks 565, aluminum heads, CP performance half/system.....
The OP and some others have factory engines filled with Dexcool from Merc.
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Old 05-05-2020 | 12:42 PM
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I wouldn't use dex cool if you have the choice. GM had a lot of gasket issues with it, and if it runs low it reacts with air and causes an acid sludge. I'd use the green stuff, doesn't "last" as long but nobody has issues with it.
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Old 05-05-2020 | 12:43 PM
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MERC 496 is DEX cool PINK stuff

other can post their engines for that info - an example - all volvo pentas us the same coolant as their diesel side - Yellow coolant.

I would not mix coolants with other style of coolants

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