Radiator fluid leak
Thread Starter
Intermediate
Joined: Aug 2021
Posts: 36
Likes: 3
From: Houston,Tx
Radiator fluid leak
I own a '73 454 57000 miles/
I have a small leak of radiator fluid ( maybe 1TBSP) coming from the bell housing seam after I have driven it. Probably losing some while. driving Bolts are tight..
Your thoughts please
Thank,s Steve
I have a small leak of radiator fluid ( maybe 1TBSP) coming from the bell housing seam after I have driven it. Probably losing some while. driving Bolts are tight..
Your thoughts please
Thank,s Steve
Safety Car
Joined: May 2001
Posts: 4,754
Likes: 1,642
From: Fairfax Virginia
Maybe the water pump seep hole dripping? A freeze plug could be failing and small hole squirting is a common starting point. The proximity to your bell housing seam really seems odd. A bad sealing Intake manifold bolt leaking coolant?
On my 1968 C3 with a 427 my heater core gets both hoses near the right rear of the engine on the firewall. They could be a source near the rear of the engine that could get on the bell housing.
It would be important to find the source of the coolant leak as they can sometimes lead to or cause catastrophic failures. A lot of folks like adding dye to the coolant and then watching with a handheld Black Light or Ultra Violet Light ad that works well.
Please let us know what you do find Skymaster7307 when you solve this leak!
On my 1968 C3 with a 427 my heater core gets both hoses near the right rear of the engine on the firewall. They could be a source near the rear of the engine that could get on the bell housing.
It would be important to find the source of the coolant leak as they can sometimes lead to or cause catastrophic failures. A lot of folks like adding dye to the coolant and then watching with a handheld Black Light or Ultra Violet Light ad that works well.
Please let us know what you do find Skymaster7307 when you solve this leak!
Burning Brakes
Joined: Jan 2003
Posts: 961
Likes: 275
From: Frederick MD
1. Intake manifold leaking externally. I'd check your oil really well and make sure you aren't dumping coolant into the pan.
2. One of the core plugs (also known as freeze plugs) on the back of the block that are concealed by the transmission bellhousing are leaking.
It might not be either of those though. Coolant/Antifreeze along with oil leaks have a bad habit of travelling all along the car due to the cooling fan pushing it. Case in point. Chasing down a pretty serious oil leak on my 2014 Chevy Cruze. Had a ton of oil collecting on the transmission. Thought it was a transmission leak. Got under it and nope it's engine oil. Started following it up and at first I thought it was one of the turbo seals. Nope turbo is dry along with the lines. Followed it up front and found it was the timing cover was leaking like crazy. So oil migrated all the way from the front of the motor to the back along the oil pan rail and then down onto to the transmission pan. So your leak could be somewhere up front too. Chase it and see if it's running from someplace. It might require you to run it in the driveway up on jackstands and under the car to find it.
1967 Pedal Car Champion
Joined: Mar 2020
Posts: 9,074
Likes: 4,208
From: US-PNW
No insult to your automotive knowledge intended but some folks have used terms mistakenly which really throws off the solution:
Bellhousing as in at the rear of the engine where it mates to the transmission, right?
Which side - passenger or driver - does the antifreeze appear on?
Is it appearing as a drip? If dripping, where exactly is it hanging onto what?
How do you know it's antifreeze - color, taste, smell?
Bellhousing as in at the rear of the engine where it mates to the transmission, right?
Which side - passenger or driver - does the antifreeze appear on?
Is it appearing as a drip? If dripping, where exactly is it hanging onto what?
How do you know it's antifreeze - color, taste, smell?
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Joined: Nov 2006
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From: Sunshine Coast, Queensland, Australia
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Cruise-In VIII Veteran
Coolant leak at the rear of engine. Bad head gasket. Bad intake manifold gasket. Or worse, freeze plug rusting through. Not that a freeze plug is an expensive part. Just pulling the engine to fix it is.
Oh, and radiator fluid. Funny. never heard that one before.
Is that sold next to the blinker fluid.
Oh, and radiator fluid. Funny. never heard that one before.
Is that sold next to the blinker fluid.
Thread Starter
Intermediate
Joined: Aug 2021
Posts: 36
Likes: 3
From: Houston,Tx
Coolant leak at the rear of engine. Bad head gasket. Bad intake manifold gasket. Or worse, freeze plug rusting through. Not that a freeze plug is an expensive part. Just pulling the engine to fix it is.
Oh, and radiator fluid. Funny. never heard that one before.
Is that sold next to the blinker fluid.
Oh, and radiator fluid. Funny. never heard that one before.
Is that sold next to the blinker fluid.
1967 Pedal Car Champion
Joined: Mar 2020
Posts: 9,074
Likes: 4,208
From: US-PNW
You can just call it anti-freeze (or coolant) since it's the only fluid with that name and has a single purpose.
Don't hesitate to ask further about the fluid leak you've seen. Anti-freeze commonly has a greenish-yellow color and kinda sticky feel and, if you taste just a finger tip amount, it is sweet - the smell is kinda sweet too. (Keep spills and drips away from pets, who like it because of its sweetness but can cause fatal kidney damage.)
Don't hesitate to ask further about the fluid leak you've seen. Anti-freeze commonly has a greenish-yellow color and kinda sticky feel and, if you taste just a finger tip amount, it is sweet - the smell is kinda sweet too. (Keep spills and drips away from pets, who like it because of its sweetness but can cause fatal kidney damage.)
Melting Slicks
Joined: Oct 2003
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From: Chapel Hill NC
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Not that it helps any but I also refer to antifreeze as radiator fluid.
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FWIW ...
I'm native US citizen & long-time SAE member. Have long worked around lotsa both journeymen and pro mechanics, racers and crew.
I refer to that liquid in radiator as coolant ... & refer to a distributor as a distributor (occasionally dist for short) ...
& refer to a module as a module ... & refer to a door panel as a door panel. When I talk tech, I typically eschew cute.
if the only spot you see coolant dripping is from a seam at bellhousing; sadly, that's likely a leaking freeze/frost plug just forward of flywheel.
I'm native US citizen & long-time SAE member. Have long worked around lotsa both journeymen and pro mechanics, racers and crew.
I refer to that liquid in radiator as coolant ... & refer to a distributor as a distributor (occasionally dist for short) ...
& refer to a module as a module ... & refer to a door panel as a door panel. When I talk tech, I typically eschew cute.
if the only spot you see coolant dripping is from a seam at bellhousing; sadly, that's likely a leaking freeze/frost plug just forward of flywheel.