Chasing down a strong rattling noise in the passenger side head of my 2003 4.6L expedition. Spark plugs are good and tight. Pulled the valve cover and ran the motor. looks like the lash adjusters are not pumping up. I replaced the lash adjusters on the passenger side and ran the motor again. Still not pumping up. I know I have oil pressure. Did an oil and filter change and the gasket from the old filter was still on the truck. when I started it I pumped half the oil out on the drive way.....


Question is, how does the valve train get oil? Through the lash adjusters and cam bearings? Where would the oil passages be located and is it possible to get a brush though them while the head is still on the motor in the Expedition?


Chris

 

The valve lifters require oil pressure to pump up. You could have a plugged oil line going up to that head.

 

So if I am staring at the head still on the motor but with the valve cover removed... Where does the oil come from? what should I look for? I know some of the 4.6 motors in the crown vics have a raised port that sprays oil but my heads don't have that. If I knew where to stick a brush to try and clean a port out I would do it.


Chris

 

I believe the rear most cam bearing cap is where the oil actually pumps up to the valve train. You would have to remove the cam and then run a wire down the oil hole you find back there. Once you can get some oil flowing you'll be able to use a motor flush and open the passage up even more. See the red arrow in the image below.

 

That is the information I was looking for.
Any possible non-kosher way to remove the cam without disturbing the cam gear and chain? Would like to be able to get at that oil passage without having to remove 153 parts off the front of the motor including the timing chain cover and chains.......




Thanks for the info,


Chris

 

Remove all of the cam bearing caps on that side and you should be able to get the back of the cam moved up and over just enough to access the oil passage.

 

Thank you, good sir! I'm on my phone, but I'm-a rep you when I get to my home computer.

 

Yeah, yeah, yeah, if I had a nickel for every time I heard that one...

 

SO Friday morning, I will "tip" the cam out of the way and check the oil passage in the rear part of the head. IF that passage is clear what would my next step be? DO the chain tensioners have something to do with oiling the heads?


Chris

 

Do you have chain slapping? If not, I suspect the timing tensioners are fine. When they go bad, you'd get chain slapping

 

According to the diagram, the oil goes first to the cam, then travels forward to the chain tensioner.

 

But say the tensioners has blown out gaskets and just pours out the oil that is fed to them, in addition to chain slapping, wouldn't that compromise the oil pressure as well? Or are there safe guards to maintain oil pressure even if the tensioners blow the gasket?

 

Great question, Skauber. One the answer to which I would love to see. my chain tensioners didn't have gaskets, and I should probably find out if they are necessary before I reassemble my motor. I found that the engine has had broken chain guides before, as evidenced by the chunks of chain guide stuck in the largest oil passage. Thanks to this thread I became more aware of the oil passages and their importance.

 

If that happened you would still have oil flow through the cam, plus the rest of the engine would also be without oil pressure, and it's not.

 

So I think I got it.

Pulled the cam cover caps off and was able to access the oil passage that feeds the valvetrain. Took me a minute to figure out which passage was which. Also as I tried plowing Marvels Mystery Oil and Engine Flush through the correct passage I noticed it would not flow. Then it hit me... The passage leads back to the oil filter. The filter has an anti- drain back valve keeping the oil from flowing from the block/head backwards to the filter/pump.

Took the filter off and presto!! was able to blow out the passage.

Put everything back together (no extra parts leftover) and ran the motor on a mix of Motorcraft 5W20, Marvels Mystery Oil, and Engine Flush for 5 minutes at idle.

NO weird noises or valvetrain clatter.

I should mention that the noise started in the passenger side head so I replaced the valve lash adjusters in that head only.
Summit Racing had the cheapest price I could find at 6.99 or 7.99 each.

Did an oil and filter change to 5QTS Motorcraft 5W20 and 1QT Marvels and will run it around for a day or so before doing another oil change or two.
Learning to trust it again.

Thanks for all the help!

Alloro, the diagram was very helpful!

Chris