New valve cover gaskets and still leaking V6 4.3

Bondo

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Ayuh,..... Mine's got the stamped steel covers, with a channel 'round the edge for the gasket, those are the plastic covers,....

I don't see a problem at the oil cap, or the vent tube,.....
No motor is spotless, unless wiped down after every trip,....
 

Scott Danforth

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oil around the breather is normal.

when I do a long run at just below WOT (about 20 miles at 4500 RPM) I will get some oil residue out of the valve cover breathers.

that is what soap and water are for.
 

Kubaat3lover

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Youre running hard your engine! I do max 3000 😬
How about this leak at the intake Maybe??
 

Lou C

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You will see oil vapors around the oil fill cap because these engines usually don't have a pvc valve to pull those into the intake manifold as on auto applications.
What I see is perhaps a small water leak, the intake gasket can leak a bit there because there are water ports in the cyl heads (they are the same casting for both sides). If the bolts that hold down the manifold are a bit loose you can get seepage there. Even though there is no water passage at the back end of the intake the water ports in the head are there. Be careful though because the Vortec torque spec is like 13-15 ft lbs or something like that. I haven't had trouble with the valve cover gaskets leaking but I have the tin covers not plastic, I don't know if they are more prone to leak or not.
 

Scott Danforth

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Youre running hard your engine! I do max 3000 😬
How about this leak at the intake Maybe??
You need to run your motor more than 3000. You are not going to hurt anything by opening the throttle a bit

My motor will spin 6000 all day long. It is fully balanced
 

Lou C

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Check the tightness of your intake manifold bolts carefully
 

Kubaat3lover

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Can I do it?
Whats the proper torque? Manual #25 says 2 different things,
on page 3A-2 : its 11 lbft but on page 3A-25 its 35lbft....
 

Kubaat3lover

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Ok, Is it safe to retoruqe them? Or remove bolt clean threats and Put some perfect seal on them? And retorque each a time ?
Are the bolts 1 time use only ?
 

Scott06

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Any ideas for Next step??…
Use your boat and enjoy it, this winter clean all the oil off the engine with and engine degreaser bet your problem goes away…

I think most of what you see here is normal I get a covering of oil in the flame arrestor and carb top wipe it down and enjoy the boat yours seems in good shape and well maintained.
 

Lou C

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Use an inch pound torque wrench carefully just make sure they are at 11 ft lbs. but first see if you really see a water leak there. It looked that way to me in the pix. It’s possible that the gasket took a set & isn’t sealing. I have an inch pound low range torque wrench for jobs like that….
 

Kubaat3lover

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I think it’s oily , I don’t know this V6s but are this manifolds prone to leak oil? Is that common maybe there’s other issue but valve covers are checked ….

@Scott06 Maybe Youre right but i Like to have clean Engine, always it was little bit oily Over the engine or bilge but this year it’s more and more and you can see 1-3 droplets dropping to the bilge after engine shut down…
 
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Lou C

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just take your time & go real easy on those, the gaskets are fragile, I actually prefer the pre-vortecs like mine were you can use the thick Fel/Pro gaskets.
 

Lou C

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Remember you must use the Vortec gaskets if you change them. They are totally different.
 

Lou C

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That one you linked at Summit is the right one. Not specifically marine like the pre Vortec is but I don’t think it matters like with head gaskets.
I’d carefully check the torque first.
 
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