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Any obvious spots to check for a Urea leak?

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Old Jul 14, 2018 | 02:04 AM
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Any obvious spots to check for a Urea leak?

We recently bought a 2010 ML350 Bluetec with about 130k miles on it. It had tons of regular maintenance as a corporate vehicle including replacing the oil cooler twice.

Unfortunately it also has a leak from the Urea tank.

Does anybody know common areas where they leak? Or if o rings are available?

So far all I'm finding are threads about failing heaters.

I just went through air spring repairs on two different cars that were the rescue of leaking o rings, not the actual air springs. And Id rather try replacing a few o rings rather than a $1000 tank. Yes I'm frugal, but more so I hate replacing perfectly good parts.

Here's what ours looked like after a recent 3 hour drive. Thankfully around town it's not so bad.
8
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Old Jul 14, 2018 | 11:45 AM
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Ouch. With such visible signs you should not have a problem to pinpoint the leak.
Just check it after shorter drive, not when everything is soaked.
Good technique is also wrap suspicious parts with paper towels.
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Old Jul 14, 2018 | 12:11 PM
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Yeah hopefully it won't be too hard to spot. But given the cost of the system I'm just hoping I don't break anything!
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Old Jul 14, 2018 | 02:27 PM
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2012 X6 35i Sport, 2013 ML 350 BT, 2019 4Runner TRD Pro, 2020 CRV-AWD
I've decided to go for the DEF/EGR/DPF delete. At 20k miles, I've already had to replace the DEF tank heater, thankfully under warranty.
Warranty's over in October, doing the delete thing shortly thereafter.
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Old Jul 16, 2018 | 02:50 PM
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The top of the tank was pretty bad. Thankfully it washes off and dissolves easily. I will keep an eye on it and check for leaks in a day or two.
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Old Sep 14, 2018 | 01:01 AM
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Just to follow up, I dropped the tank and found that the heater or pump was replaced previously and they forgot an o-ring. I bought one from the hardware store and replaced it and the leak is fixed!

Im pretty sure it was a professional shop that last touched it. Oh well, a couple hours and 40 cents solved it.
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Old Sep 14, 2018 | 05:13 AM
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Glad you got it figured out, and sad that a professional shop would forget something so simple!
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