Cooling System Capacity for 8.1 ???

[LeeSoCal]

I cannot locate the cooling system capacity for my Dolphin. I flushed it today and I could get a little more than a gallon of DexCool in it. I know the block is full of water and I did drain, refill with water 3 times and then did it again with distilled water. So I know there is water in the block. I could only get about a gallon in the radiator and that seems to be too little for that system. I don't know of any way of getting the coolant out of the block. Any help from you guys who have done this will be helpful.

[LeeSoCal]

I cannot locate the cooling system capacity for my Dolphin. I flushed it today and I could get a little more than a gallon of DexCool in it. I know the block is full of water and I did drain, refill with water 3 times and then did it again with distilled water. So I know there is water in the block. I could only get about a gallon in the radiator and that seems to be too little for that system. I don't know of any way of getting the coolant out of the block. Any help from you guys who have done this will be helpful.

[TOMFEN]

Lee
I had my cooling system flushed and refilled at Brazels RV in Feb. On the maint sheet they used 2 gallons of Dexcool. I think the tech said they used a 50/50 mix which would make a total of 4 gallons for the complete system. Just checked my maint manual, it doesn't say what the capacity is, just to use a 50/50 mix of drinkable water and dexcool.
Hope this helps
Tom

[edgray]

LEE: In the owner's manual I have it states the cooling system capacity for the 8.1L is 23.5 Quarts.

To properly flush the system, I think you need to either run the engine up to operating temp. or remove the thermostat to allow flow through the block.

FWIW, GM claims the Dex-Cool has a service interval of 5 years or 150,000 miles. ED

[DriVer]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">To properly flush the system, I think you need to either run the engine up to operating temp. or remove the thermostat to allow flow through the block. </div></BLOCKQUOTE>Most often the lower radiator hose is removed to facilitate draining the engine. There are also threaded plugs (2) in the side of the engine which aid in draining the block down.

If someone is contemplating draining their cooling system a cooling system a cleaner can be added directly to the radiator and the engine run up to operating temperature. If the cooling system is full you may need to drain down some coolant to add the cleaner. Do not add the cleaner to the recovery bottle.

Restore the drain plugs in the block and use a wrap of Teflon tape. Replace both thermostat and radiator cap to complete the cooling system maintenance. Add a 50/50 mix of coolant, "Dexcool" or whatever floats your boat just so long as you are comfortable with the coolant you are using. Some owners have switched back to more conventional coolants like Prestone BUT I would stay with the OEM spec for the coolant that was originally installed.

In order to make sure you get at least a 50/50 mix and given that the cooling system can hold 23.5 quarts in a minimum configuration, that's just 5.8 gallons of coolant, you may have to add a bit more coolant in consideration for the Winnebago Motor-Aid system as well.

I would add 2.75 gallons of coolant straight up and then top off the system with water as required unless you want to mix up 6 gallons of 50/50 coolant.

[LeeSoCal]

Thanks Ed and DriVer. I will have to remove the block plugs to get the right amount of Dexcool installed. I was trying to avoid pulling the block plugs. Without pulling the block plugs, you can only get about 5 quarts of Dexcool in it. I need to put in about 12 quarts. Thanks for your help.

[M&EM]

Just finished flushing and replacing my coolant. What a pain!

Used Prestone flush treatment, 2 containers per instructions.

Removed 2 block drain plugs and replaced them with 3/8" stop valves.

Radiator drain valve was odd in that it looked like a tamper proof screw head and was difficult to open.

Removed engine heater hose at heater control valve to allow block to vent better and as a high point for refill.

Flushed several times with fresh water, and drained.

Refilled with 3 gallons Dex using above high point fill method. Added another 2 1/2 gallons water until overflowed at radiator cap opening. Closed up system.

Filled over flow tank with fresh water (1/2 gal) and ran engine to operating temp. No leaks, good to go for 3-4 more years.

Hope this helps someone.
Marty

[Full-Timers]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by DriVer:Add a 50/50 mix of coolant, "Dexcool" or whatever floats your boat just so long as you are comfortable with the coolant you are using. Some owners have switched back to more conventional coolants like Prestone BUT I would stay with the OEM spec for the coolant that was originally installed. </div></BLOCKQUOTE>DriVer,
I thought you had to use the Dexcool or equivalent (pink stuff) or you will screw up the system and have to change your coolant more often.

[DriVer]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Full-Timers:
DriVer, I thought you had to use the Dexcool or equivalent (pink stuff) or you will screw up the system and have to change your coolant more often. </div></BLOCKQUOTE>There are differing avenues of thought on the matter and I chose to offer both. Using a conventional coolant isn't going to harm anything however the service interval would be definitely shorter.

Some folks simply are not on board with Dexcool however we certainly would not want those owners to go with straight water.

I personally will be using Dexcool.