radiator? problem
Thread Starter
6th Gear
Joined: May 2022
Posts: 6
Likes: 1
radiator? problem
In the process of fixing my grandpas 96 c4. it turns over and runs but after i park the car i notice it’s smoking. the radiator reservoir always goes down. after looking at a diagram it’s j. the same area as the bleeder valve but is it supposed to take that much coolant and smoke every use? any help would be great thank you
Thread Starter
6th Gear
Joined: May 2022
Posts: 6
Likes: 1
nope, i thought i would’ve been that head gasket too but no big white clouds leaving the exhaust. oil isn’t milky it was thick and seemed fine. after i park it, it just steams up like in the video for like 10 minutes
Le Mans Master
Joined: Oct 2004
Posts: 7,706
Likes: 485
From: Everett WA
C4 of Year Finalist (appearance mods) 2019
So one thing to note is that on the radiator the two side "caps" are made of plastic while the rest of the radiator is made of aluminum. Those caps expand and contract at rates different than the aluminum. Over years of time very tiny crack can occur where the plastic joins the aluminum. What happens is that when the radiator is hot the crack opens up and coolant sprays out often in a very fine mist. You won't notice this when the engine is cold. That's why at the end of a ride coolant has been lost.
Two ways you can determine if this is your issue (requires replacement of the radiator) get the car on a lift and let the engine run and get up to operating temp and then observe things from underneath. Another way would be to pressurize the system and see if you can detect the spray.
Not saying that this is your issue ..... but it's certainly a possibility.
Two ways you can determine if this is your issue (requires replacement of the radiator) get the car on a lift and let the engine run and get up to operating temp and then observe things from underneath. Another way would be to pressurize the system and see if you can detect the spray.
Not saying that this is your issue ..... but it's certainly a possibility.
Safety Car
Joined: Mar 2017
Posts: 4,197
Likes: 1,321
From: LeClaire Iowa
So one thing to note is that on the radiator the two side "caps" are made of plastic while the rest of the radiator is made of aluminum. Those caps expand and contract at rates different than the aluminum. Over years of time very tiny crack can occur where the plastic joins the aluminum. What happens is that when the radiator is hot the crack opens up and coolant sprays out often in a very fine mist. You won't notice this when the engine is cold. That's why at the end of a ride coolant has been lost.
Two ways you can determine if this is your issue (requires replacement of the radiator) get the car on a lift and let the engine run and get up to operating temp and then observe things from underneath. Another way would be to pressurize the system and see if you can detect the spray.
Not saying that this is your issue ..... but it's certainly a possibility.
Two ways you can determine if this is your issue (requires replacement of the radiator) get the car on a lift and let the engine run and get up to operating temp and then observe things from underneath. Another way would be to pressurize the system and see if you can detect the spray.
Not saying that this is your issue ..... but it's certainly a possibility.
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Team Owner
Joined: Sep 2003
Posts: 25,393
Likes: 2,741
An eBay search for GM # 12556260 will get the OP a very good image of the pipe/fitting's seals etc.
Drifting
Joined: Jun 2020
Posts: 1,355
Likes: 396
From: Northwest Ohio
... seems to be from somewhere on the back half of the engine but that can be deceiving... something spraying/dripping onto the exhaust manifold/cat maybe (crossover tube or leaking out of the rear of the head or hose clamp or hose or ...)? Even a split hose could cause this (check all hoses!). There is no coolant circulating in the intake manifold, so that is ruled out.The OP needs to look carefully with a strong flashlight for wet coolant and/or observe while running (while hot, and be careful). A pressure test could help identify it too. Hopefully it will be obvious.
Team Owner
Joined: Aug 2008
Posts: 33,028
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From: Rochester NY
St. Jude Donor '09 thru '26
I have not watched the video yet, but will point out what you likely already know. It's not uncommon for us to say "smoking" when we actually mean "steaming". I have been guilty of saying "I had 'white smoke' out the tailpipe" when I obviously meant steam.
My point is that losing the coolant, it it's not making puddles, would cause steam. If you are seeing smoke, that would be a different issue, which may be, or may not be, related to the loss of coolant.
My point is that losing the coolant, it it's not making puddles, would cause steam. If you are seeing smoke, that would be a different issue, which may be, or may not be, related to the loss of coolant.