Hot coolant leaking on drivers side floor board

222,000 MILES • 4.7L • V8 • 4WD • AUTOMATIC
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STEVEN54789
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I replaced a heater core in my vehicle in November of 2018. Yesterday while I was driving the heater core failed and started leaking hot coolant and water on the drivers side floor broad the car did not overheat to where it was on hot it was just above normal. after the heater core failed I bypassed it and ran the hoses together. But now my radiator is hissing and letting steam and coolant and water out of the very top right corner where it meets the plastic. what can i do to temporarily fix it? When I replace the radiator should I replace the whole cooling system?
Dec 24, 2018 at 10:06 PM
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ASEMASTER6371
  • ✓Experienced Mechanic
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Good morning,

That sounds like the radiator itself is leaking at a seam.

I would replace the radiator as you should never use any sealer. it will contaminate the system.

https://www.2carpros.com/articles/how-to-replace-a-car-radiator

Replace the thermostat as well. it very well may be the reason for the overheating and the failure of the new heater core.

https://www.2carpros.com/articles/replace-thermostat

Roy
Oct 16, 2020 at 4:47 AM
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JEM B HOFFMAN
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Okay, but i never intended on putting anything inside the radiator itself but seal it up on the outside with high heat silicone or glue or epoxy. I had a 1996 GMC Saffari van that the plastic housing had cracked my grandma gave me some high heat epoxy and it lasted another six months before it completely cracked.
Oct 16, 2020 at 4:47 AM
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ASEMASTER6371
  • ✓Experienced Mechanic
  • 52,796 POSTS
You can try it but most of the time it never works. besides, when it does come off, it will be larger than the original and could cause more damage.

just be careful. the correct repair is to replace the radiator and the cap.

Roy
Oct 16, 2020 at 4:47 AM
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JEM B HOFFMAN
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Ya I know, just payday is still a couple days away I'm replacing it. I just want something to seal the outside where I see the steam escaping from it so I can still drive it it's my only transportation.
Oct 16, 2020 at 4:47 AM
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ASEMASTER6371
  • ✓Experienced Mechanic
  • 52,796 POSTS
try the sealer on the external. do not add the sealer to the coolant.

leave your cap a little loose as well and keep an eye on the level.

I totally understand the economics side. car repairs are not cheap.

Roy
Oct 16, 2020 at 4:47 AM
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