2nd blown oil filter gasket and coolant mixing with oil? Help with isolating the causes?

SkylabTech86IDI

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Almost forgot, as for the cowl seal, I always install them with a nice bead of silicone to stop leaks too.
We all agree that I need a cowl seal hence buying one, hence buying one from RockAuto ($19 shipping, ouch!)
So I’m assuming that we’re all suspecting the rainwater that pools in the valley pan might be seeping past the CDR valve throat gasket?

I’ve yet to take it apart and see how the condition of the seal is
 

Nero

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My dad's old truck that we sold had a bad cowl seal, and it actually would fill up the intake until it filled up a cylinder. Took out the glow plugs and evacuated all the water. Oil was a little milky after that. Changed it and was good as new.
 

ROCK HARVEY

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The valley pan has a drain hole at the rear that should let water drain down the back of the engine. If it’s blocked and your CDR tube is totally disintegrated, water could be getting in. But if that’s the case you should be able to see standing water in the valley pan. I’d shine a flashlight down there and look, and jab a screwdriver into the drain to clear it while you’re at it.
 

Brian VT

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I'm seeing water on my air cleaner cover after a rain. Should there be a seal between the hood and the cowl? I'm not seeing anything listed on Rockauto.
 

Nero

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If you have water forming on your air filter housing, your cowl seal has failed, or may not be present. Water buildup there can get into the engine.

I don't know if it is on rock auto, but LMC has them for both bull and brick noses. Look at item 1

 

Brian VT

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If you have water forming on your air filter housing, your cowl seal has failed, or may not be present. Water buildup there can get into the engine.
Dang. Now I'm freaking out. I guess I'd better run out and put a floor mat on there.
It's been like that for almost a year (since I got the truck).
The air filter cover seems to be mostly water-tight (water sits on there).
Would that be the only point of entry into the engine if my valley pan drain is functional?
 

Nero

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Yeah pretty much. Either air filter or CCV drain. My dad's old truck, the grommet for the bolt actually let water into the cylinder. That's when we found out about the cowl seal.
Here's what I'd do in your situation, dry off the top of your air filter, take it off and look down your intake. If it's dry, you're most likely fine.
 

Brian VT

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After looking at links and videos it seemed to me that the "cowl seal" was under the metal that the wipers are on. That's why I had asked if there were 2 pieces to be concerned with. I have one that's just bolted the front of the "cowl" and looks easy to replace. The one under the vented metal looks like a project.
 

Nero

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All trucks I've ever seen, including all the ones at the wrecking yard, the cowl seal is just an L shaped seal that screws into the face of the cowl lip. So I'm not sure what the other one you're referring to is.
 

IDIBRONCO

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After looking at links and videos it seemed to me that the "cowl seal" was under the metal that the wipers are on. That's why I had asked if there were 2 pieces to be concerned with. I have one that's just bolted the front of the "cowl" and looks easy to replace. The one under the vented metal looks like a project.
I've seen them called "hood seals".
 

ROCK HARVEY

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Some people, including myself, have had success buying a roll of “L” shaped garage door seal and making our own cowl/hood seal. It was much cheaper and works great
 
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