Help Engine coolant question
Thread Starter
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Joined: Sep 2016
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Help Engine coolant question
Hey Guys
i need some input from y’all if you got a minute. I see bubbles in my coolant tank? I researched on the forum here, I know it might be a head gasket but let me fill you in on everything. Combustion gas test- negative
Pressure test- holds 16psi for hours
no visible leaks
no white exhaust
car does not overheat
car runs as strong as it ever did
no milky froth in oil
no residue on coolant cap or oil cap
verified coolant cap doesn’t leak
im stumped any ideas?
thanks in advance
im stumped
i need some input from y’all if you got a minute. I see bubbles in my coolant tank? I researched on the forum here, I know it might be a head gasket but let me fill you in on everything. Combustion gas test- negative
Pressure test- holds 16psi for hours
no visible leaks
no white exhaust
car does not overheat
car runs as strong as it ever did
no milky froth in oil
no residue on coolant cap or oil cap
verified coolant cap doesn’t leak
im stumped any ideas?
thanks in advance
im stumped
Thread Starter
Advanced
Joined: Sep 2016
Posts: 95
Likes: 9
so is it normal then. I’ve read in other posts where some guys say it normal for a c5? A lot of conflicting info. First time I noticed it and only because I was doing some other none coolant related work?
Drifting
Joined: Jan 2015
Posts: 1,256
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From: Pennsylvania
Nothing to be concerned about especially if you just were in the system and it is working all the little trapped air pockets out. But most likely you are seeing the stream of coolant returning back to the tank and it is causing a splash that looks like bubbles.
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Drifting
Joined: May 2007
Posts: 1,552
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From: Mid Ohio
Technically the fill bottle is called a "degas bottle".
One of its multiple functions is to use it as the highest spot in the cooling system so as to remove air bubbles that are formed on hot metal parts of the engine. The flow rate is sufficient enough to sweep them off the cylinder walls and around the exhaust valves and suspend them until it reaches the degas bottle.
This makes the fluid going to the engine more dense / less aerated and therefore more efficient for cooling.
Based on what your seeing its likely normal operation. You might consider changing the fluid if its more than 3yrs old.
(I was a OEM water pump engineer in the 90s ;-) )
One of its multiple functions is to use it as the highest spot in the cooling system so as to remove air bubbles that are formed on hot metal parts of the engine. The flow rate is sufficient enough to sweep them off the cylinder walls and around the exhaust valves and suspend them until it reaches the degas bottle.
This makes the fluid going to the engine more dense / less aerated and therefore more efficient for cooling.
Based on what your seeing its likely normal operation. You might consider changing the fluid if its more than 3yrs old.
(I was a OEM water pump engineer in the 90s ;-) )
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4-5 years, MAX. I go 5 years, MAX, on my C5 using dexcool. Older dexcool formulations would coagulate/partially solidify if you never changed it. I don't want to find out if newer formulation does. Change it every 54-60 months, you'll be fine.......
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