Upper and lower intakes, large amount of oil

[Buggyman]

Hey guys,

Have a 2000 3.0 Flex fuel, heads are off at the machine shop and I am working on cleaning the gasket surfaces right now. I was wondering how much oil in the lower and upper intakes is normal? I know the bottom of the lower intake covers the top of the block but I have oil all up into the intake, a lot of it looks caked and baked on, there is also a large amount of carbon buildup where the fuel injectors were. The fuel injectors are old and look very dirty, plan to replace them along with the PCV valve and tubbing. Also the top of the lower intake is caked with old oil along with the bottom of the upper intake, and side of the motor. The ventilation tubbing that runs from the oil cap to the intake was completely snapped off at the cap with a large amount of oil surrounding the break, not sure if some of this external oil is only from that or something else. Does this vent line to the oil cap provide a source of clean air only or does it also pull a vacuum on the valve covers?

Thanks for any advice!

Philip

 

[Rearanger]

I was wondering how much oil in the lower and upper intakes is normal?

Can't say what's normal but I recently had my upper intake off. Lots of oil and some small amount in lower intake with a tiny amount burned. The PCV on these trucks seems to allow a lot of oil into the intake. For a time I used a catch can, but even though it caught a lot oil (and water) oil still found it's way into plenum. I have since removed catch can.

The fuel injectors are old and look very dirty, plan to replace them...

I sent mine to witchhunter.com. They test, clean, replace seals and return with before/after report. Might be cheaper than new or rebuilt.

Does this vent line to the oil cap provide a source of clean air only or does it also pull a vacuum on the valve covers?

This vent allows filtered air into the engine block to replace the air put into the plenum through PCV valve. The vent should only draw air from intake. This vent air is taken out of the metered air supply but put back in through the PCV to maintain fuel trims.

 

[stmitch]

Ford's are fairly well known for syphoning oil through the PCV system, back into the intake. EGR also adds a bunch of black sooty stuff that likes to stick to the intake runners. Sounds pretty typical to me.

Polishing the runners and removing as much of the casting roughness as you can will reduce it if you're concerned about it (and maybe help it breathe a bit better). Otherwise, I'd just get it as clean as you can before putting it back together.

 

[Buggyman]

Thanks for the feedback, I will probably replace the PCV valve and tubing and I have access to an older valve cover that does not have a broken vent tube that I will replace this one with. Should I replace the fuel injectors? If so, what are your thoughts on the cheaper ones that you can buy at autoparts stores? I feel like something has to be wrong if they're only $40 each and motorcraft is $100. Has anyone had success sending them off to be cleaned/reconditioned? They have 250,000 miles on them.

Thanks!

 

[mikersoft]

I just went through the same process... I removed my engine & completely took it apart, down to the short block (2000 3.0 Flex w/manual)

To clean the oil & carbon build up from both my upper & lower intake manifolds, I used Easy Off oven cleaner, w/various scrub brushes, and a power washer. I found it worked pretty well, especially when I let it soak in the oven cleaner for awhile.

I thought about creating a project thread with some photos and thoughts on various problem/solutions I encountered. Good luck & let me know if I can help in any way based on my recent experience.

-Mike

 

[Rearanger]

Has anyone had success sending them off to be cleaned/reconditioned? They have 250,000 miles on them.

I have done this twice, once on Ranger (recently) and once on other vehicle since I had it apart anyway for other stuff. Neither was with your mileage.

Look up to previous post to see where I sent them.

 

[evanesce69]

What is your driving style, stop and go or long haul? Stop and go driving can cause the oil to get dirty quicker and pick up significant amounts of moisture, looking milky in the valve covers. Not changing the oil regularly can also cause buildup/caking of oil/dirt under the intake. High mileage motors without regular maintenance are prone to these conditions. Dirt and carbon buildup in the upper intake is common but exaggerated when a faulty PCV valve or dirty/missing air filter are present. Routine maintenance is key. As for injectors, looking at the pattern created inside the intake runners can give you an idea as to their condition. Runners that have a large oval clean area directly under the injector are probably ok. An irregular shaped pattern or none at are are indicators of a clogged or faulty injector. Using a multimeter to check continuity and ohm value of each injector can also be a valuable tool in diagnosing fuel injectors. I do not recall the resistance value, but they should be very close to each other... Infinite or no resistance at all is a electrical failure the requires replacement. With a splotchy pattern you may be able to get by with a quality injector cleaner additive to your next tank of fuel.

 

[Buggyman]

I ended up using a metal pick to scrap the large chunky stuff off, I then took a wire brush to it then sprayed it down with degreaser and scrubbed with another wire brush then ran an old T shirt back and forth through each passage before spraying it out with choke cleaner really well. It took some elbow grease but came out very clean. This vehicle was given to me from a family member after they blew a head gasket so I am not very aware of its driving history. I replaced the PCV valve and might look into the fuel pressure damper/regulator next to ensure it does not continue to run rich. With new head gaskets, new exhaust valves and clean intake it runs much, much better.