Water leak from heater box

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jonesy318
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Tue Jul 19, 2016 7:28 pm

Hi guys, has anyone had issues with the gasket on the heater box leaking where it bolts to the bulkhead. I've tried 2 new gaskets from bmw and still it leaks when washed, and comes in on the corner of the gasket. How tight should the retaining bolts be, just wondered if I'm doing them up to tight. Or have you got any tips to rectify it, it's really doing my head in now.
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brutus
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Tue Jul 19, 2016 9:25 pm

u may need to change the heater matrix, ,, a pipe under the dash, right side of the glove box,that wot usually cuses water in the car from the bulkhead :?
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Brianmoooore
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Wed Jul 20, 2016 1:34 pm

If I'm reading this right, this isn't a coolant leak, that brutus's heater matrix change might cure, but rain or washing water leaking into the car via the heater box.
Drain for that is the 'elephant's trunk' in the engine compartment, on the bulkhead, to the right of centre. Often found to be blocked with debris, and often found to be brittle and in need of replacement.
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biffer
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Wed Jul 20, 2016 4:12 pm

on my car,i found that the actual shallow gully at the bottom of the heater -box that the water travels along to reach the 'trunk' was itself half-blocked with crap.

this meant rain-water never made it to the 'trunk' but instead over-flowed into car-interior via heater-box.

clearing out the gully itself sorted it out in this instance.
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jonesy318
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Wed Jul 20, 2016 6:59 pm

Brian is right, it's inly when washed. The car is absolutely clear of any crud as its been off road for years being rebuilt...

It's almost exactly as biffer describes it as the gully does fill up but again it's clear, I'm totally lost at what to do to rectify it though!!
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