GRRRRRR.....coolant leak.
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From: Knox TN
GRRRRRR.....coolant leak.
So, got the z out this morning to drive to work. All is well. Got to work and get out....smell coolant. Look and notice coolant dripping under my car. I open the hood and on the driver side of the car, coolant seems to be dripping or running out around the upper hose some where. Not exactly sure where its spewing from. Any ideas of what to check or is there anything common that happens with this cars as of leak prone areas?
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From: Knox TN
Look at the plastic tank on the end of the radiator. They are known to leak at the rubber seal between the aluminum body of the radiator and the plastic tank.
If that is it you can replace the tanks but most opt to replace the entire radiator with an all aluminum aftermarket setup.
If that is it you can replace the tanks but most opt to replace the entire radiator with an all aluminum aftermarket setup.
I am still pretty unfamiliar with this car since I have only had it about 2 months and is my first chevy. Came from a 94 fully built Supra.
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Both ends of the factory radiator have plastic tanks. There is a rubber seal between the ends of the aluminum radiator and the tanks. I used to have pics of my OEM radiator before I upgraded but can't find them right now. Maybe still on my laptop. If I can find them I'll post in this thread.
The upper radiator hose attaches to a spout on the drivers side end tank and the lower radiator hose attaches to a spout on the passenger side end tank. I don't remember exactly how the tank is held onto the radiator body for certain, but it may be crimped. The tanks can be replaced (if they are in fact the source of your leak) but I would not do that if it were my car. There are decent new radiators that are all aluminum including the tanks on the market for something like $250.
If I were replacing the radiator on a stock C5 that is how I would go.
Clean off as much of the coolant as you can and then start and idle the car until the temp comes up to normal. Then carefully watch and see where the leak is coming from. It could be the hose itself but I suspect it will be something other than the hose and clamp.
The upper radiator hose attaches to a spout on the drivers side end tank and the lower radiator hose attaches to a spout on the passenger side end tank. I don't remember exactly how the tank is held onto the radiator body for certain, but it may be crimped. The tanks can be replaced (if they are in fact the source of your leak) but I would not do that if it were my car. There are decent new radiators that are all aluminum including the tanks on the market for something like $250.
If I were replacing the radiator on a stock C5 that is how I would go.
Clean off as much of the coolant as you can and then start and idle the car until the temp comes up to normal. Then carefully watch and see where the leak is coming from. It could be the hose itself but I suspect it will be something other than the hose and clamp.
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The tank on at the fender with the Red coolant on the passenger side still shows that it is fairly full of coolant. Do you think I should just keep an eye on engine temps on the way home? What kind of TEMP should I start getting cautious at and what is OK to stay under? As long as I make it home I should be fine.
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From: oregon
it's been my experience that at this age, especially if you have an average 80k mile car that the whole cooling system should be replaced and here's why
waterpumps are usually what kick off the replacement. hoses sometimes drizzle but it's usually the plastic tank or waterpump
if all your hoses haven't been replaced they need to be. at 10 years old they have lived their life. the plastic tank will be very brittle if it's not already leaking. when i was changing my water pump simply pulling a hose off the oem tank was enough to crack it.
radiators are also full of crap and like the coolant tank the end tanks get brittle on the radiator. you also get some degree of scaling in the radiator and cleaning one will take over an hour to really do a decent job. on top of that a brand new ac delco rad is $188 shipped on amazon
i hate doing labor on something twice and it's only 500 dollars or so to replace your entire cooling system
list of parts
Ac delco 20889 radiator $188.16
Ac delco water pump 251-744 $177.61
Ac delco water pump inlet w/ stat 15-11057 $29.30
Ac delco 18021L hose $27.52
Ac delco 24388L hose $25.35
Ac delco 24458L hose $14.59
GM hose 10229491 $24
Gates 18127 $12.62
Gates 5/8” heater hose {runs small} 2ft section
GM coolant tank 10430189 $69.95
waterpumps are usually what kick off the replacement. hoses sometimes drizzle but it's usually the plastic tank or waterpump
if all your hoses haven't been replaced they need to be. at 10 years old they have lived their life. the plastic tank will be very brittle if it's not already leaking. when i was changing my water pump simply pulling a hose off the oem tank was enough to crack it.
radiators are also full of crap and like the coolant tank the end tanks get brittle on the radiator. you also get some degree of scaling in the radiator and cleaning one will take over an hour to really do a decent job. on top of that a brand new ac delco rad is $188 shipped on amazon
i hate doing labor on something twice and it's only 500 dollars or so to replace your entire cooling system
list of parts
Ac delco 20889 radiator $188.16
Ac delco water pump 251-744 $177.61
Ac delco water pump inlet w/ stat 15-11057 $29.30
Ac delco 18021L hose $27.52
Ac delco 24388L hose $25.35
Ac delco 24458L hose $14.59
GM hose 10229491 $24
Gates 18127 $12.62
Gates 5/8” heater hose {runs small} 2ft section
GM coolant tank 10430189 $69.95
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I made it home...most of the time the car ran 199 to 201 for coolant temp. Not until I got close to home did it get any above that. I stopped close to work at autzone and got a jug of premixed 50/50 dex cool just in case. Didnt have any issue....but now I gotta trouble shoot where and why.
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It did end up being the plastic tank on the driver side of the radiator. I pulled the shroud that goes across the top and looked at where the hose connects to the tank on the driver side. Sure enough, there are some tiny cracks that I guess are expanding when heating up and allowing coolant to seep through.It wasnt the seal of it to the radiator core though. I looked while still warm, would wipe the coolant away with my finger, and it would then again start to pool up slowly. So I now have to find another stock radiator or some other resolution.
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From: oregon
the ac delco deal on amazon was the best deal i could find. if you were in oregon i actually have a spare used one i'd give you
when you order that radiator get your upper and lower coolant hoses too. they need to be changed at this age and if you break your cooling system into parts the radiator and upper & lower hose are all part of the same job
i swear GM designed the cooling system to fail all at the same time. your water pump and expansion tank are next on the list
when you order that radiator get your upper and lower coolant hoses too. they need to be changed at this age and if you break your cooling system into parts the radiator and upper & lower hose are all part of the same job
i swear GM designed the cooling system to fail all at the same time. your water pump and expansion tank are next on the list
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From: Knox TN
anyone who says it is a 2 man job to take out the radiator and fans isnt trying hard enough. Got them out myself a few mins ago. Just gotta make sure you get everything pushed out of the way when you are pulling it up and out.... 
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From: Knox TN
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From: Knox TN
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Can anyone give any pointers on the full up process on these cars? I am guessing it all gets filled through the tank that is up on the passenger side fender well? how do you go about it without getting a ton of air in the system? Seems like opening it up to replace the rad would introduce lots of air into the cooling system.???
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From: NS