Replaced heater core but still leaks!!
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Re: Replaced heater core but still leaks!!
if you replaced the core with a new one then it will not be leaking. The leak has to be identified but simple explanation is hose connection??
- ak_perth
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Re: Replaced heater core but still leaks!!
Hi flamo,
I dont know what year your car is but I found a pdf which tells you how to remove the dash for 89-93 MX5 if that's any help?
www.miata.net/garage/DashRmv_89_93.pdf
Cheers
AK
I dont know what year your car is but I found a pdf which tells you how to remove the dash for 89-93 MX5 if that's any help?
www.miata.net/garage/DashRmv_89_93.pdf
Cheers
AK
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Re: Replaced heater core but still leaks!!
If your kinda lazy, you can bypass it, and just not have a heater core with flud running in it...
every ounce counts
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Re: Replaced heater core but still leaks!!
If it's leaking in the passenger footwell, it could be the air conditioning as there is a tube there that gets rid of the water that is pulled out of the air.
Lift the carpet on the passenger's footwell, and you should see a plastic tube with a T piece in it.
This tube can come undone, and when it does, it drips water into the footwell.
Lift the carpet on the passenger's footwell, and you should see a plastic tube with a T piece in it.
This tube can come undone, and when it does, it drips water into the footwell.

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Re: Replaced heater core but still leaks!!
It is possible, but not likely, that the new core that you installed is faulty. 
Not having used the method that you used, I do not know if this might have happened, but if you had to apply any force to position the core properly, you may have opened up a joint or something similar.
The air-conditioning drain is your best bet, for a cheap fix! How would you feel if that was the problem all along, and you didn't need to replace the heater core? I think that I can guess ...


Not having used the method that you used, I do not know if this might have happened, but if you had to apply any force to position the core properly, you may have opened up a joint or something similar.

The air-conditioning drain is your best bet, for a cheap fix! How would you feel if that was the problem all along, and you didn't need to replace the heater core? I think that I can guess ...

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Re: Replaced heater core but still leaks!!
I've replaced a heater core - I feel your pain.
If you had access to a car like this, would you take it back right away? Neither would I.
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Re: Replaced heater core but still leaks!!
I recently had a leaky heater core and i replaced it via the drivers footwell but ended up snapping one of the heater core controls and had to remove the whole dash to plastiweld one tiny broken bit. While i was there i found heaps od dodgy wiring done by previous owners, almost as bad as the stuff i found on the loom at the computer when i wired in my Link.
Dann
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- jerrah
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Re: Replaced heater core but still leaks!!
Would love to know how to replace the heater core without pulling the dash? I did mine about two years ago and fingers crossed it lasts another 20 years.
NitroDann my ECU wiring thankfully is in good shape, but there's a real mess on the drivers side. I took out about a mile of wire that wasn't required. If I was doing it again I would have probably found a unmolested replacement loom.
NitroDann my ECU wiring thankfully is in good shape, but there's a real mess on the drivers side. I took out about a mile of wire that wasn't required. If I was doing it again I would have probably found a unmolested replacement loom.
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Re: Replaced heater core but still leaks!!
I got mine replaced by a mechanic under statutory warranty.
For those interested to know, a heater core replacement in an mx5 will set you back around 2 weeks of no car and $980
The two weeks was most likely because I live in tassie and we have very little parts down here!
For those interested to know, a heater core replacement in an mx5 will set you back around 2 weeks of no car and $980
The two weeks was most likely because I live in tassie and we have very little parts down here!
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Re: Replaced heater core but still leaks!!
jerrah wrote:Would love to know how to replace the heater core without pulling the dash? I did mine about two years ago and fingers crossed it lasts another 20 years.
NitroDann my ECU wiring thankfully is in good shape, but there's a real mess on the drivers side. I took out about a mile of wire that wasn't required. If I was doing it again I would have probably found a unmolested replacement loom.
You look under the middle of the dash looking from the pedals towards the passenger side of the car, the heater core has a plastic cover over it. take it off, undo the clamps. Slide the heater core out.
Dann
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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.
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