Car was overheating, water in the exhaust

DREA626

MEMBER
2007 NISSAN MURANO
6 CYL
2WD
200,000 MILES

Hello, I had my truck overheat and we noticed water in the exhaust and bought the blue devil sealant, however when we used it yesterday, we did a radiator flush and did not let the engine cool down before adding the sealant and the thermostat was not removed. I let it run for 2 hours based on reviews that said it was best to leave that long instead of an hour. However, there is still water coming out of the exhaust, and a bit of smoke, not as much as before, but it did not seal it completely. Can you share why and what can I do to fix it?

Wednesday, June 15th, 2022 AT 10:31 AM

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

One thing to always remember when using any type of additive to 'seal' leaks or blown head gaskets, is that depending on the amount of leak, it may or may not fix it completely or at all.
So, it is not if you have done something incorrectly, it's more of the nature/size of the leak.

If you are still having the issue, the likely solution is to replace the gasket and do the necessary repairs in case of wrapped or cracked cylinder heads.

Unfortunately, many times the simple fix of adding sealant just does not fix the issue.

Also, the best way to find out if the cylinder head is cracked or wrapped is to remove it.

Let me know of any questions.
Thank you.

https://www.2carpros.com/articles/head-gasket-blown-test

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