Heater Core Failure
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Joined: Aug 2003
Posts: 62
Likes: 0
From: Roseville CA
Heater Core Failure
Blew the heater core today. First time I have ever experienced this problem, so I"m not sure what results to expect. The passenger foot well had a flood of coolant. I replaced the heater core eight years ago during restoration to hopefully avoid this problem. However, I have only used the heater once since restoration.
Things I'm curious about:
Will the flood of coolant destroy the carprt requiring replacement? The carpet is original, in great condition showing little or no wear.
Because I essentially don't use the heater I'm considering blocking it off.
I would appreciate thoughts on this course of action.
Thanks in advance for your thoughts and wisdom.
Things I'm curious about:
Will the flood of coolant destroy the carprt requiring replacement? The carpet is original, in great condition showing little or no wear.
Because I essentially don't use the heater I'm considering blocking it off.
I would appreciate thoughts on this course of action.
Thanks in advance for your thoughts and wisdom.
Melting Slicks
Joined: Oct 2004
Posts: 3,345
Likes: 87
From: Northern MN
St. Jude Donor '13-'14-'15-'16-'17
I don't know if it will ruin your carpet or not. It did in mine when mine had a small leak. I will say this, if you just used the heater once or twice in eight years, that is the most probable reason it went out on you. I run mine at least twice during the spring and fall months to make sure that it circulates and doesn't simply sit and corrode. You can block the heater off but I don't know how you get it to look right under the hood when doing so. Maybe someone else knows how to do that.
Drifting
Joined: Feb 2006
Posts: 1,840
Likes: 29
From: Towaco NJ
I guess you have a 66 from your profile. So I can not guess why your heater failed other than you may of revved it too high before the T-stat opened. My good buddy did that in his 66.
Beyond that, My red car has Mercedes carpeting, thick padding and a porous heat shield. One night doing a hard pass, the 90 Degree rubber heater fitting in a C1 let go. Flooding the pass. side with coolant. Knowing that the Anti-freeze will never evaporate and
not wanting to replace the custom carpeting, I jacked the car up on the opposite side and flooded the pass. side with water for several hours so the water would run out over the sill plate. After that I used a wet/dry vac and sucked out all the water I could. After that, I set up a fan to evaporate any moisture left. I think it took 3-4 days.
Absolutely no evidence of a coolant leak.
As for blocking the heater off. I block the one in my black car off because I race it at high RPMs they tend to break them. I use valves to do this. I blocked mine off last time in 2003. I opened them last month for the first time since then, to go to a Winter car event in January. Wow, that heat felt good.
Beyond that, My red car has Mercedes carpeting, thick padding and a porous heat shield. One night doing a hard pass, the 90 Degree rubber heater fitting in a C1 let go. Flooding the pass. side with coolant. Knowing that the Anti-freeze will never evaporate and
not wanting to replace the custom carpeting, I jacked the car up on the opposite side and flooded the pass. side with water for several hours so the water would run out over the sill plate. After that I used a wet/dry vac and sucked out all the water I could. After that, I set up a fan to evaporate any moisture left. I think it took 3-4 days.
Absolutely no evidence of a coolant leak.
As for blocking the heater off. I block the one in my black car off because I race it at high RPMs they tend to break them. I use valves to do this. I blocked mine off last time in 2003. I opened them last month for the first time since then, to go to a Winter car event in January. Wow, that heat felt good.
Racer
Joined: Jul 2006
Posts: 382
Likes: 77
From: minnesota
Heater core
Mine blew last summer, What a mess antifreeze all over passenger side. in the console and some on drivers side. I just kept dumping gallons of water with a little bit of carpet cleaning soap in it on the carpet. Then suck it up with a Rug Doctor carpet cleaner hand attachment. I tried the shop vac but it didn't have enough suction. The last few times I dumped the water in it was just plain water no soap. The floor pan is dished down so the water just sits there and doesn't end up flowing to the back of the car. I put a shut of valve in the heater hose after that. I do use heater in spring and fall, so it does get opened to limit corrosion in the heater core.
Le Mans Master
Joined: Apr 2001
Posts: 9,556
Likes: 288
From: Granbury Texas
Under ther carpet on the passenger side is a small rubber grommet (looks like a rubber freeze plug) set in the floor pan which can be opened or removed to drain the water out. I race my car with an intact heater and it's never been a problem on track. However both my 63 and 67 have blown the heater core on the street and filled the passenger side with water. "They all do it"
Race Director
Joined: Jan 2002
Posts: 15,354
Likes: 2,726
From: Close to DC
C2 of the Year Finalist - Modified 2020
The heating system on NON A/C cars circulates coolant all the time. It does not have a valve of any sort to stop or restrict the flow. If you put a valve in yourself, then you stop the flow or if you loop the under hood hoses too bypass the core, then it is out of the loop, and that is considered "blocking of the heater". Pulling on any of the ***** only changes the temp and direction of air flow to the interior. If a core has sat out of the loop with some coolant it could corrode and when you put it back in the loop it could burst from the new pressure/temp. Also, if and when you put on or take off hoses you need to do it VERY gently. When putting on, use a dab of grease and when taking off for replacement, slit the hose end. If just servicing the system, use a cotter key puller and slide the end under the hose lip, then move it around the circumfrance carefully and the hose will slip off. If your car has A/C, then you do have a valve and that is a hole different animal and could fail more frequently. 
Dennis
Dennis
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From: Washington Michigan
Le Mans Master
Joined: Feb 2008
Posts: 5,214
Likes: 447
From: NJ Hockey beer league
The heater in a non-A/C midyear is "ON" (flowing coolant through the core) all the time; the controls have no effect on coolant flow - they just change the position of the airflow doors in the case. A/C cars also flow coolant full-time unless the temp cable is pushed all the way in for maximum cooling.
Pilot Dan
