Gallons antifreeze required to get to -25F

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advanced concept energy solutions

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Can't seem to find how many gallons of water in the engine cooling system including lines to and coil in the water heater. How many gallons of antifreeze do you guys up north put into a drained system.
Also could someone send me how to search archives AGAIN. Lost the email along with most of my brain.

Jon Darcy ACES
North Jersey 76 stretch, flares, 4 bag, Alcoa's, bunkhouse,MAC Dash,Manny Trans, FiTech FI,Honda 6010
 
Jon,

Cooling system capacity is 21 quarts ref: MM-X-7525 / Section - General Information / Page 0-11 / Recommended Fluids and Lubricants.

Regards,
Rob M.
USAussie - Downunder
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426

-----Original Message-----
From: Gmclist [mailto:gmclist-bounces] On Behalf Of Advanced Concept Energy Solutions
Sent: Wednesday, November 02, 2016 11:36 AM
To: gmclist
Subject: [GMCnet] Gallons antifreeze required to get to -25F

Can't seem to find how many gallons of water in the engine cooling system including lines to and coil in the water heater. How many
gallons of antifreeze do you guys up north put into a drained system.
Also could someone send me how to search archives AGAIN. Lost the email along with most of my brain.

Jon Darcy ACES
North Jersey 76 stretch, flares, 4 bag, Alcoa's, bunkhouse,MAC Dash,Manny Trans, FiTech FI,Honda 6010

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GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Jon

You appear to be an email user -- so perhaps the easiest way to search would be to go to the forum page

http://gmc.mybirdfeeder.net/GMCforum

Once there use the search button up near the top line,
Others may have better options.

Hope this helps.

Oh -- you could also go to bdub.net GMC section and use the search block.

Dennis

> Can't seem to find how many gallons of water in the engine cooling system including lines to and coil in the water heater. How many gallons of
> antifreeze do you guys up north put into a drained system.
> Also could someone send me how to search archives AGAIN. Lost the email along with most of my brain.
>
> Jon Darcy ACES
> North Jersey 76 stretch, flares, 4 bag, Alcoa's, bunkhouse,MAC Dash,Manny Trans, FiTech FI,Honda 6010
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

--
Dennis S
73 Painted Desert 230
Memphis TN Metro
 
Mixing pure anti-freeze half and half with DISTILLED water is considered optimum and will take you to around - 40 (C or F).

Mac in OKC

Sent from my iPad

>
> Jon,
>
> Cooling system capacity is 21 quarts ref: MM-X-7525 / Section - General Information / Page 0-11 / Recommended Fluids and Lubricants.
>
>
> Regards,
> Rob M.
> USAussie - Downunder
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
>
>
> -----Original Message-----
> From: Gmclist [mailto:gmclist-bounces] On Behalf Of Advanced Concept Energy Solutions
> Sent: Wednesday, November 02, 2016 11:36 AM
> To: gmclist
> Subject: [GMCnet] Gallons antifreeze required to get to -25F
>
> Can't seem to find how many gallons of water in the engine cooling system including lines to and coil in the water heater. How many
> gallons of antifreeze do you guys up north put into a drained system.
> Also could someone send me how to search archives AGAIN. Lost the email along with most of my brain.
>
> Jon Darcy ACES
> North Jersey 76 stretch, flares, 4 bag, Alcoa's, bunkhouse,MAC Dash,Manny Trans, FiTech FI,Honda 6010
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
The capacity of the GMC is somewhere around 5.5 gallons. So I use 6 gallons as the capacity. Then I install 3 gallons of non-diluted antifreeze and
fill the rest with distilled water ($.88 a gallon at Walmart). That takes the freezing point down to less than -32F.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
DONT OVER DO IT!

Keep in mind, the higher % of glycol you use, your cooling system will be harder to pump (higher viscosity/higher pressure drop), Lower thermal
conductivity (bad, glycol holds the heat and doesn't want to let it go) and A lower volumetric heat capacity which means you would need to pump more
antifreeze mix to do the same work as a lower solution.

Do use a hydrometer to ensure you are in a safe range (don't guess) use an inhibitor or additive like "water wetter" or Lucas "super coolant" and
ensure you do not have any electrical conductivity see Ken's tutorial http://www.gmceast.com/technical/Burton_Grounding_GMC_Motorhome.pdf

--
Sean and Stephanie
73 Ex-CanyonLands 26' #317 "Oliver"
Hubler 1-Ton, Quad-Bags, Rear Disc, Reaction Arms, P.Huber TBs, 3.70:1 LSD Honda 6500 inverter gen.

Colonial Travelers
 
Buy 4 gallons and use 3 gallons...put 2.5 A/F in and the same amount of distilled water and mix the last half gallon 50/50. Top it off with that. Make
sure the reservoir is about half full(not all the way full). Run the engine to temperature and drive the coach around some curves and up to highway
speed to get the air out. Refill the overflow reservoir at least half full before the engine cools so it can draw some back in. Check that reservoir
in about a half hour after shutdown and keep it half full. Check it again when everything is stone cold to make sure it is still half full.
--
Terry Kelpien

ASE Master Technician

73 Glacier 260

Smithfield, Va.
 
It's always easy to remember to Google "GMCNet Archive", then search that
library (Read only Google Group).

Ken H.

> Jon
>
> You appear to be an email user -- so perhaps the easiest way to search
> would be to go to the forum page
>
> http://gmc.mybirdfeeder.net/GMCforum
>
> Once there use the search button up near the top line,
> Others may have better options.
>
> Hope this helps.
>
> Oh -- you could also go to bdub.net GMC section and use the search block.
>
> Dennis
>

> > Can't seem to find how many gallons of water in the engine cooling
> system including lines to and coil in the water heater. How many gallons of
> > antifreeze do you guys up north put into a drained system.
> > Also could someone send me how to search archives AGAIN. Lost the email
> along with most of my brain.
> >
>
 
A few years ago I got tired of spilling antifreeze everywhere, then going
through the fill/run/fill/cool/run/fill/iterate routine to get all the air
out of the system. That high-mounted heater core makes that an essential
process -- unless you go this route:
http://www.gmcmhphotos.com/photos/g4278-simple-2fno-spill-2fno-air-cooling-system-filler.html

Ken H.

> Buy 4 gallons and use 3 gallons...put 2.5 A/F in and the same amount of
> distilled water and mix the last half gallon 50/50. Top it off with that.
> Make
> sure the reservoir is about half full(not all the way full). Run the
> engine to temperature and drive the coach around some curves and up to
> highway
> speed to get the air out. Refill the overflow reservoir at least half full
> before the engine cools so it can draw some back in. Check that reservoir
> in about a half hour after shutdown and keep it half full. Check it again
> when everything is stone cold to make sure it is still half full.
> --
>
 
I think you will find that the actual capacity is closer to 6 gallons. The book spec does not include the overflow bottle and the house water loop.
Also if you have an aluminum radiator that also increases the volume some more. So with a 6 gallon capacity, use 3 gallons of antifreeze. If you are
over on antifreeze percentaage, it will not be enough be enough to make any difference.

BTW, 60/40 rather than 50/50 mix is common in areas of northern Canada and Northern Alaska. Even if the GMC were only a 5.5 gallon capacity (which I
doubt), 3 gallons antifreeze to 2.5 gallon water mix would only be a 54% mix.

What we are interested in is freeze protection, so I little over mix is a good cushion.

I really think we are picking at nits here. We are talking about 1 quart difference here.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
Ken,

I agree that the 21 quart capacity as listed in the MM does not include the house water loop, however, when you drain the system how
do you get the water out of that loop?

It also does not include the overflow bottle either.

Plus the aluminum radiator holds more also.

Since my GMC's in the USA are based in Houston and I ain't goin' to Northern Canada or Alaska in the winter I'll stick with 50/50.

I need to flush Double Trouble's cooling system that has engine cooling water supplied to the water heater and an aluminum radiator
so I'll measure how much drains out (if I can remember).

Regards,
Rob M.
The Pedantic Mechanic
USAussie - Downunder
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces] On Behalf Of Ken Burton
Sent: Thursday, November 03, 2016 3:07 PM
To: gmclist
Subject: Re: [GMCnet] Gallons antifreeze required to get to -25F

I think you will find that the actual capacity is closer to 6 gallons. The book spec does not include the overflow bottle and the
house water loop.

Also if you have an aluminum radiator that also increases the volume some more. So with a 6 gallon capacity, use 3 gallons of
antifreeze. If you are over on antifreeze percentage, it will not be enough be enough to make any difference.

BTW, 60/40 rather than 50/50 mix is common in areas of northern Canada and Northern Alaska. Even if the GMC were only a 5.5 gallon
capacity (which I doubt), 3 gallons antifreeze to 2.5 gallon water mix would only be a 54% mix.

What we are interested in is freeze protection, so I little over mix is a good cushion.

I really think we are picking at nits here. We are talking about 1 quart difference here.
--
Ken
 
That is not the problem Rob.

When I drain the system, I always flush the system with the engine running using clean water for 10 or 15 minutes. So whatever remains on the bottom
of the radiator or the bottom of the engine or the heater loop is 99% water.

Measuring what you drained does not account for how much is left that did not drain. So put 3 gallons in it attempting to achieve 50% plus and you
will never have to worry about it freezing. If you are a few percent over, who cares? It is better than being short. I have seen on a few rare days
temps in the -20s. One night many years ago my car thermometer read -28F on a late night trip back from Indianapolis.

So 3 gallons it is. I can always measure it with a hydrometer if I have any questions.

I usually check my freeze levels on all vehicles once a year. I do not check the GMC because it is parked inside at the airport and I'm not taking it
out when it is that cold.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
Ken B and Rob M are both correct. I think the spec is after a rebuild (fill from dry). I never "flush" as you are adding tap water and or flush
chemicals you never get out 100%. Like the front oil pan remnants, if system is dirty, just shorten the drain intervals. If radiator is really bad,
remove and have cleaned or serviced professionally. If you drain/fill 50/50 every 2 years you won't have issues. However what seams like 2 years ends
up being 5 in reality and the additives in the product are exhausted. So I try for opening the petcock yearly--- which puts me on a perfect 2 year
plan. I'm way better with my other fluids as they are easier to dispose of correctly. 50/50 is best compromise for most conditions. As you go higher
cooling system performance drops. Freeze protection gets better as you increase concentration (to about 70/30 max) at which point it deterioratates
rapidly and freeze point climbs. As in most situations (eg adding too much ZDDP to your oil) more is not better. But going slightly higher in conc
beats freezing up north.
--
John Lebetski
Woodstock, IL
77 Eleganza II
Source America First
 
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