Diagnosing a coolant leak

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Guran
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Diagnosing a coolant leak

Postby Guran » Fri Nov 05, 2010 11:28 am

After putting up with a slow leak of coolant over recent months (~70mL/hr while driving or as engine cools), I finally got around to taking off the undertray from my NA6 this morning so that I could track down the source of the leak. Judging from the photos below, it seems to be mainly coming from behind the crank pulley.

OK, give me the bad news. Is it the water pump? Wouldn't surprise me if it is because I suspect it wasn't replaced when the timing belt was done (long before I took ownership). If the water pump has gone, then I might as well get the timing belt done at the same time since it appears that it needs to be removed it to get access anyway.

Viewed from underneath
Image
IMG_0329 by Guran5, on Flickr

Viewed from the top
Image
IMG_0332 by Guran5, on Flickr
Standard 2006 NC - YouTube
WP 1:11.89 | SMP-S 1:05.90 GP 1:54.93 N 1:18.09 L 2:22.49 | PW 1:02.52
PI 2:00.55 | W-S 1:12.44 W-L 1:43.36 | SR 1:33.25

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Dweezle
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Diagnosing a coolant leak

Postby Dweezle » Fri Nov 05, 2010 11:59 am

My guess is water pump.

The Malibu looked exactly like that when I decided to go in for a look.

Replaced pulleys, belt and water pump.

Quite a scary job for me!! Haha
But glad I did it.

It's all there to do once you get that far :).

I now have no more coolant levels dropping and no more green undertray !!





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deviant
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Re: Diagnosing a coolant leak

Postby deviant » Fri Nov 05, 2010 12:04 pm

Looks like the water pump to me to. I had a workshop do my timing belt not long after I picked the car up and they found a problem with the water pump during the change...it was actually well and truly rooted with stuffed bearings and a hairline crack in the housing but somehow the belt tension was holding it all together, it was when they relaxed the belt and the pulley moved forward and fluid started coming out that the problem was found! Very strange!

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Guran
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Joined: Sun Feb 15, 2009 6:42 pm
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Re: Diagnosing a coolant leak

Postby Guran » Fri Nov 05, 2010 12:07 pm

Thanks guys. I'm not risking my dodgy mechanical skills with such a big job and will be taking it to the pros. Hope I can get it done before the next club trackday.
Standard 2006 NC - YouTube
WP 1:11.89 | SMP-S 1:05.90 GP 1:54.93 N 1:18.09 L 2:22.49 | PW 1:02.52
PI 2:00.55 | W-S 1:12.44 W-L 1:43.36 | SR 1:33.25


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