How can I stop a leak in my heater core?

Question

I made a mistake and asked this question earlier but said 'radiator core'. Apologies to all.

It's expensive to fix because it's behind the dash and I haven't the money. The mechanic wants to disconnect the hoses and bypass it but I won't have any heat.
Some folks said I should pour in some stop leak but that's when everyone thought it was just the radiator.
Can stop leak beads fix the heater core also?

I have have condensation (sweet smelling like antifreeze) blow out of the ducts and the windshield fogs up when I turn on the heat.

Answer 1

Stop leak can stop small leaks, but can also plug cooling system. Not that hard to fix, go to AutoZone online look-up your car and it will show breakdown. Heater core's range from $25.00 - $45.00 it's the labor that's expensive.

Answer 2

The heater core is just the same as the radiator core. Anything like StopLeak will work in either. Some cars have plastic parts where the hoses join the core that tend to crack over time, I would worry about these breaking right off . The best fix would be to remove and replace the heater core. This will probably take a lot of time by yourself or an exspensive shop Stop Leak is certainly cheap and simple. Some people worry about plugging up the whole cooling system, but I have not had any trouble.

Just read the answer about checking for a head gasket leak that might blowing a lot more pressure into your cooling system and heater that it was designed to stand. That is a good point !

Answer 3

Heater Core Stop Leak

Answer 4

Sometimes but heater cores have a tendency to permanently plug if you use stop leak. Worth a try though...

Make sure you don't have a bad head gasket putting pressure into the cooling system. I had two cars that did that and they blew the new heater core.

Not all head gasket leaks will show up with water in the oil. I have repaired 7 or 8 cars with severe coolant pressure problems due to a bad head gasket. One my son drove for 6 months without the radiator cap and adding water every 200 miles or so.

Answer 5

Let me throw in another vote to bite the bullet and replace it. Over the years, I've had a few leak and always wound up replacing them. Think of this, when the heater core leaks, it is blowing a mist of anti-freeze into the interior of your car and you are breathing this. Very unhealthy for you and your passengers. Try and find a way to get done, without bypassing the heater. Good luck

Answer 6

I bought 1998 Ford Explore XLT V8 5.0 and the heater core has been bypassed, how can I check to see if the Heater Core is bad before having to take my dash apart to replace it?

Answer 7

I'll give you the same answer. If you want heat, get it fixed. If you don't want heat bypass it. Everything else is hootspfa and will cause you problems such as loss of coolant , overheating, and engine damage. Go ahead, be cheap and put some stop leak or, as I call it "stopped up" in her. Just about the time you are out in the middle of West Pucklehuddy, it'll give out on you and then you will ask, "Oh why oh why was I so cheap".

Answer 8

I know money is tight but if you use any of this junk you you are just going to be wasteing your money it wont work for long i know the best thing to do is get a backyard mechanic to put it in for half the price of a garrage . you could end up blowing a head gasket runing your car hot and thats what will happen messing with stop leak .

Answer 9

No adding stop leak to the radiator won't affect your heater coil. The only real option is to replace the coil (haven't heard of bypassing it, but I suppose it's possible).

I think the first thing would to make sure it is the heater coil. Did you have condensation (sweet smelling like antifreeze) blow out of the ducts?

Answer 10

...i have replaced a couple...usually the a/c system is not far behind from the need of replacement parts...

...heater core is best replaced--the part itself only cost about $70--shop around- negotiate the labor costs with a mechanic..

it can be done...good luck