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Valve cover issue

Hunter

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Jan 8, 2016
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Location
Pa
Putting my 440 together, and I noticed when installing valve cover bolts that the lower bolts don’t sit flat on the covers , didn’t think to much off it at the time , just put oil in motor and oil is leaking up threw the bolt hole , I am using 440 source gaskets and black Mopar performance valve covers , I don’t think it’s a gasket or cover problem , also put Crome cover on it and same thing ,Looks like don’t put equal pressure on valve cover has any run across this
 
Could it possibly be the bolt length ? I've had to cut down valve cover bolts before.
 
No, checked that even tried different length bolts , the head of the bolt does not sit flush on valve cover , from some quick research looks like it might just be the Mopar performance cover , they site flat on the head but I think the top side of cover is not level with the head causing a gap and uneven pressure
 
No, checked that even tried different length bolts , the head of the bolt does not sit flush on valve cover , from some quick research looks like it might just be the Mopar performance cover , they site flat on the head but I think the top side of cover is not level with the head causing a gap and uneven pressure
In your 1st post you said you had the same problem with a different ( chrome) vakve cover. If you've tried different length bolts, all that leaves is either crud in the holes, or holes incorrectly bored ( assuming theyre not cross threaded). Imo
 
Motor is clean no crude , threads are not stripped or cross threaded , with valve covers on it does look like holes are bored incorrectly, with them off they seem normal , just seems odd ,that’s why I was asking if any one has seen this
 
Try running long bolts in the holes with no valve covers on, and see if they look perpe dicular.
 
Will try that and follow up later this week thanks
 
as stated above the bolts go in at a slight angle . if you over tighten them, especially with steel covers they will split the gasket or smash it out of place creating leaks.
 
Thanks Moparedtn thats what I was looking for , going to try the Mopar washers and stud kits , thanks again to all for quick response ,
 
I have the cast aluminum valve covers on my 440/493.
I've noticed that to get the best seal, I have the bolts threaded a couple of turns, then I slide the covers up toward the carburetor as far as they go, then I snug up the bolts. It seems that if I let gravity allow the covers to sit, the bottom gasket rail is not fully and squarely covered by the valve cover and oil leaks out. The mounting holes are larger than the bolts enough to allow more movement than there should be.
 
Had a similar issue. It turned out the gasket landing area around the bolt hole was cast with a slope on it. My fix was to dope it up with silicone under and over the gasket.
 
I have the cast aluminum valve covers on my 440/493.
I've noticed that to get the best seal, I have the bolts threaded a couple of turns, then I slide the covers up toward the carburetor as far as they go, then I snug up the bolts. It seems that if I let gravity allow the covers to sit, the bottom gasket rail is not fully and squarely covered by the valve cover and oil leaks out. The mounting holes are larger than the bolts enough to allow more movement than there should be.
Yeah, the holes have to be bigger to allow for the slope on the mounting studs/bolts...
 
After replacing the cam on my 383, the right bank Mopar Performance valve cover leaked. I snugged it down and it still leaked. Snugged it again and the flange broke. A little RTV on both sides of the gasket finally sealed it up.
 
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