95eagle
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Re: Coolant Level for Charging

Fri Sep 13, 2019 12:36 pm

LeftieBiker wrote: [quote=95eagle post_id=567547 time=<a href="tel:1568400125">1568400125</a> user_id=10277]
Progress. Found source of leak. A quarter inch hole in the so called degas tank. Anyone know what the term degas refers to?

Just a guess, but it may refer to the air that gets mixed into the coolant by the pumps.
[/quote]

Hmmmmmm!!! I thought there was not supposed to be any air in the coolant system?

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Re: Coolant Level for Charging

Fri Sep 13, 2019 5:11 pm

Hmmmmmm!!! I thought there was not supposed to be any air in the coolant system?
There isn't supposed to be, but it can still get in, which is why I guessed the tank was to remove stray gases.
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Nubo
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Re: Coolant Level for Charging

Fri Sep 13, 2019 7:03 pm

95eagle wrote:
Fri Sep 13, 2019 11:42 am
Progress. Found source of leak. A quarter inch hole in the so called degas tank. Anyone know what the term degas refers to?
https://patents.google.com/patent/US5329889A/en
I noticed you're still working with polymers.

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Re: Coolant Level for Charging

Fri Sep 13, 2019 7:32 pm

If the coolant system is pressurized like an ICE vehicle I suppose some air could be drawn back in as it cools. Or maybe there are hot spots that vaporize tiny amounts of coolant? Or something else. Maybe someone from SAE engineering will chime in with the answer.

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Re: Coolant Level for Charging

Fri Sep 13, 2019 8:21 pm

Nubo wrote:
Fri Sep 13, 2019 7:03 pm
95eagle wrote:
Fri Sep 13, 2019 11:42 am
Progress. Found source of leak. A quarter inch hole in the so called degas tank. Anyone know what the term degas refers to?
https://patents.google.com/patent/US5329889A/en

From the above link:
BACKGROUND OF THE INVENTION

In certain automobiles manufactured by various auto companies, the cooling system used for the engine is of the so called "closed" type wherein a plastic degas tank is provided that is physically separated from the radiator and is closed by a pressure cap of a type normally located on the radiator. The degas tank is operated under internal pressure of about 15 PSI gage and is connected to the engine and the radiator so that the coolant circulates through the degas tank. One purpose for the degas tank is to allow entrained air and gasses in the coolant to be separated from the coolant as the coolant flows through the degas tank. In order to allow the air and gasses to escape into the degas tank, it is normal to provide the degas tank with a number of chambers or compartments which are connected in series through windows or openings formed in the ribs separating adjacent chambers so as to allow the coolant to flow between the chambers
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Nubo
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Re: Coolant Level for Charging

Fri Sep 13, 2019 11:00 pm

I had a first-year Renault Alliance, and after some time I noticed the coolant temperature would start to fluctuate. It got worse and worse until I eventually stumbled upon "bleeding" air from the coolant to put things back to normal. After that I periodically bled air from the system by loosening a hose at the top of the radiator; eventually I put in a brass fitting to make the chore easier. Years later when I had to go for emissions testing, the mechanic was surprised to see an Alliance still running, and with that many miles on it. He said they mostly died from overheating "something about air in the system" :lol:
I noticed you're still working with polymers.

henrydehoja
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Re: Coolant Level for Charging

Sat Sep 14, 2019 6:16 pm

LeftieBiker wrote:
Fri Sep 13, 2019 11:45 am
95eagle wrote:
Fri Sep 13, 2019 11:42 am
Progress. Found source of leak. A quarter inch hole in the so called degas tank. Anyone know what the term degas refers to?

Just a guess, but it may refer to the air that gets mixed into the coolant by the pumps.
The degas tank basically removes the air/gas (i.e., de-gas) from the coolant liquid. This gas needs to be removed because it reduces the performance of the coolant liquid. A lot of different engine cooling systems use the same approach.
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Re: Coolant Level for Charging

Sat Sep 14, 2019 7:12 pm

At any rate, it seems to be just another name for a familiar part: the coolant reservoir.
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Nubo
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Re: Coolant Level for Charging

Sat Sep 14, 2019 8:26 pm

LeftieBiker wrote:
Sat Sep 14, 2019 7:12 pm
At any rate, it seems to be just another name for a familiar part: the coolant reservoir.
There's an important distinction. An overflow reservoir is only connected to the system when the pressure cap opens, and doesn't perform a degas function (unless inadvertently during an overflow event). A de-gas tank is part of the pressurized system. This is why the plastic is so much thicker.
I noticed you're still working with polymers.

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