Spray of water from exhaust manifold above O2 sensor

zaayer

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Jul 24, 2022
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I have a 2012 Volvo Penta 8.1 GXCi-Q with the O2 sensors. There is a small spray of water coming from above the O2 sensor on the port side. Any ideas what the problem could be? I have attached a video in the picture. I appreciate any help.
 

ESGWheel

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Aug 29, 2015
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Zaayer,
There is some issue with posting videos and pics. One suggestion that works is to post the vid on you tube and then provide the link. With the video, I am sure folks will be able to chime in if still unresolved.
 

zaayer

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Jul 24, 2022
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I got busy after posting this orginally. I have uploaded the video and posted it to youtube.
Video of spray. This spray is actually coming from the starboard exaust manifold just above the precatlyst O2 sensor. Any idea what is going on or if it is repairable? Thank you for you help!
 

Scott06

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I got busy after posting this orginally. I have uploaded the video and posted it to youtube.
Video of spray. This spray is actually coming from the starboard exaust manifold just above the precatlyst O2 sensor. Any idea what is going on or if it is repairable? Thank you for you help!
Probably cracked Looks like a pin hole near. I would dissasemble and use acetone or pressure test to see what's is going on. Are they made of aluminum or cast iron. Aluminum could probably be repaired but cast iron not so much
 

zaayer

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It's heavy so not aluminum. There is not much rust on the inside of the manifold. Any chance a welder can seal it?
 

Scott06

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It's heavy so not aluminum. There is not much rust on the inside of the manifold. Any chance a welder can seal it?
While you can weld cast iron with tig and the correct rod it is hit and miss And requires preheating and cool down of the part before and after welding.

the most honest answer a welder can give you is I will try but make no gauarantee.… it is also double wall. Better way to repair castings is locknstitch or other similar cast iron repair
 

Mc Tool

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Probably cracked Looks like a pin hole near.
Drill and tap it and shove a mild steel grub screw in there, or even a couple of overlapping ones .:cool: ,its not like its under any load
 
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Scott Danforth

Grumpy Vintage Moderator still playing with boats
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The downside to exhaust manifolds......If it's leaking on the outside...... It's leaking on the inside
 

Mc Tool

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The downside to exhaust manifolds......If it's leaking on the outside...... It's leaking on the inside
Yeah but you cant see it leaking on the inside ;) ha ha , good point tho. I dont have a whole big lot of experience with marine manifolds ( other than Im lookin for some for a 215 Buick /3.9 Rover V8 ) but Im sure there will be a way to fix this without replacement .
Does there appear to be any exhaust gas comming out with the water ? That looks to my optimistic eye like maybe there is a small void in the casting water jacket and maybe an external plug may seal it.
 

zaayer

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Jul 24, 2022
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There does not seem to be any exhaust gas coming out. I had the manifolds off last year and they were very clean. There was a very slight layer of rust that could be removed with a paper towel. I would call it a dusting of rust. No flakes. I am hoping that this is just a defect durning the casting. Is that something that can happen?
 

Mc Tool

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Yep , there can be bubbles ( voids ) in the casting ( shouldnt happen but....) and Im hoping that there is such a void just below the surface that has just rusted thru , or the recess machined for the O2 sensor is to deep , or a bit of both , either way my 1st move would be to look at bunging a large flat washer under that O2 sensor ( maybe a custom fettled washer ) with some sealant on it .
 

zaayer

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Jul 24, 2022
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Update. I had someone look at it and they think the manifolds are coming to the end of their life. Now I need to find some replacements. :(
 

Scott06

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Update. I had someone look at it and they think the manifolds are coming to the end of their life. Now I need to find some replacements. :(
as expensive as the manifold replacement is compared to it to a new or rebuilt long block if they leak water into engine …
 
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