Oil in intake manifold

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Justin Allen

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Hey guys. 2013 LR4 with 82k miles. Well maintained. Finishing up the front and rear coolant pipe replacement and as I went to put the intake back on, I noticed a few ounces of oil in it. Turned it up and let it drain. It appears to be coming from the hose connecting into the valve cover on the passenger side as the connection point has a light oil film on it. Now considering this is the first time I've had the manifold off, I have no idea how long it may have taken to accumulate those few ounces. Where should I go from here?

Search isn't really returning anything meaningful except its perhaps somewhat common?
 

jlglr4

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It’s common. That PCV vent hose let’s oil through. Below is a pic of my supercharger at 52K miles showing the accumulated oil - couple ounces. Many people have noted similar amounts of oil, and a dealer tech once told me they all do the same.
EE995EC7-FFC8-475D-B1BD-D2CD1D5A65BC.jpeg
 

jlglr4

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Yes, if the diaphragms are getting stiff or torn. At 82k, it’s probably due. But it won’t likely reduce the amount of oil that gets past. You see how much oil I had at only 52K miles, and the PCV was fine. Some people have put oil catch cans on the system, if you are really interested in reducing oil escape trough the PCV.
 

Justin Allen

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Well, just pulled both diaphragms and they’re in fine condition. No tears holes etc. So that can’t be the cause of the oil.
 
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16FujiDisco

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I think even a fully functioning pcv let's oil through. The pooling oil is just a result of oil vapor returning to liquid form once the engine cools down. I would guess that the amount that trapped (1-2 oz) is just a result of all the nooks and crannies in the supercharger plus the extra heat generated by these engines.

The pcv system works under higher vacuum than idle to relieve built up pressure in the crankcase. Its still important to keep them functioning to prevent oil vapor constantly getting sucked into the intake and fouling plugs and building carbon on the backs of valves.

To really reduce if not eliminate this oil buildup, the catchcan is the only route.
 
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jlglr4

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The valve covers also have oil separator baffles that are supposed to let oil vapor drop out before it gets to the intake. I don’t think they work very well and, with all the leaking valve covers I read about on these forums, I think the oil must be blocking up the system to some degree and raising the pressure in the valve covers. I believe it was a documented issue in the older discovery series (which had a removable oil separator), but I’ve not heard anyone discussing the reason for all the valve cover leaks in the newer cars.
 

Pfunk951

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Thanks for setting up this post, I just pulled mine and it's a little oily also..

Does anyone know where to get a catch can for these, or do you just have to rig one up?

And what happened last weekend that inspired all of us to go after the crossover pipes at the same time?! That damn chip in our Covid vaccines must have shorted out:laugh:

Thanks again,

Mike
 

Justin Allen

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To be honest, I looked for catch cans and there is little to no info on the what and how front so I think I'm just resigning myself to the fact that it's going to happen and perhaps periodically clean it out. Heck, plenty of guys on this forum are over 150k on their vehicles and probably didn't run a catch can so I'm just going to let it be. And considering mine had never had the rear pipe replaced, and no record of any other job that would have required intake removal, it could very well be that what I saw had accumulated throughout the entire 82k miles. Now, that I've cleaned it, I don't suspect it'll build back up that fast.

I started on my front/rear replacement 3 months ago and I'm still not done! Truck hasn't moved in almost 4 months. But I guess that's what happens when you get Covid, go on vacation, and just get busy with life!
 

sfdaytona

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So I just did my cross over pipes/water pump etc, and noticed oil leaking out of my intake and onto the workbench. I don't know if it'll work, but I have a Mishimoto Oil separator in my Focus ST. Like the LR4, it's a DI motor, and this is a common issue on that ecoboost motor. There are quite a few options for other applications out there, I'm sure something can be made to work on an LR4.

Anyway, the unit I have has a catch can with a drain plug on it. I'll play around with some ways to set one up on my LR4 and report back.

If any of you have had your intake off and looked at the valves, the amount of crap you see when you look at the intake ports of the cyl head, it's very apparent the "factory" oil separator is useless.
 

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