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Engine comaprtment covered in oil 700 1987

My son's 1987 740 has a problem with the engine slowly puking out its oil out of the filler cap in the valve cover. This symptyom appeared after I had my friend/mechanic install a new flame trap and a new engine wiring harness. I consulted this board at the time and it was the general consensus to look at the flame trap so I asked my mechanic to check on the flame trap and he said it wasn't clogged (it was brand new). My mechanic said he didn't know what could be causing the problem and it was left alone. At the time the car had 160k miles. Today we were looking at a different problem and noticed that the oil "blowby" problem has worsened. We removed all the air intake hoses from the air filter box to the throttle body and found that the hoses had a lot of oil in them, the throtle body had a pretty good coating of oil also, as did the entire other side of the engine it has a thick coat of oil from the valve cover down to the oil filter.
We removed the flame trap and it was oily but not clogged. The car now has 175k miles.
Any ideas what could be causing this problem?
Thank You
Jorge








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    Engine comaprtment covered in oil 700 1987

    Did you check the two nipples on the plastic piece that goes into the top of the flame trap (as well as the hoses) to see if they were clogged. Be careful cleaning, if you have not done so, since the plastic nipples break easier with age. If clogged try running a stiff wire or small finishing nail thru it.

    Less likely that breather box below the flame trap is clogged, but certainly worth taking off and looking at it. It is held by two hex bolts.

    I find it worth the time to remove the throttle body to get to the flame trap and breather box. While I'm at it, I clean the throttle body. If the throttle body has never cleaned within the 160,000 miles, it should make a world of difference in idle and power. Won't help you oil problem, but may be part of your performance problem.

    Gary








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    Engine comaprtment covered in oil 700 1987

    Simple, more than likely it is more than the "flame trap/oil trap", probably the oil trap box below the intake manifold is plugged up, especially when synthetic oil is not used religiously, they are prone to get "caked up" over time with oil. This box can be removed and degreased or simply replaced if you'd rather, (access is a little though being under the intake manifold but do-able). The PCV Nipple on the intake manifold (the nipple that connects to the flame trap) also must be remove and cleaned thoroughly. All related hoses also need to be checked thoroughly and degreased, the o-ring also must be replaced for the oil trap box (it is basically a distributor o-ring. You'll probably have to pry off the old o-ring with a flat blade screwdriver being it has probably hardened. This is all very important to reduce blowby, in many cases simply replacing the flame trap/oil trap just doesn't cut it, especially if the oil trap box below and/or PCV nipple is plugged. Chances are they both are. You can spray inside these components carburetor cleaner or soak them in simple green and hot water, rinse then soak them repeatedly, also use a flatblade screwdriver to scrape the crud off. You can use a tiny pin to poke through the PCV Nipple on the intake manifold. I'd bet this will reduce your blowby significantly if not eliminate it. From there only after you are finsihed of course, I'd cover all electrical components (you can tie plastic bags around them), spray the engine compartment down generously with concentrated simple green then spray the engine down with a hose that has a pressure nozzle. Degrease as much as possible. Replace the oil cap seal also. Then monitor the oil leakage so you can see what seals may have been damaged by your excess blowby. Good Luck! Brandon








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      Engine comaprtment covered in oil 700 1987

      After you are sure the oil seperator is clean or replaced and all the associated plumbing is open you will want to replace the flat rubber ring "gasket" between the oil filler cap and the cam cover.

      Randy








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      Engine comaprtment covered in oil 700 1987

      Oh yeah, and forget, you can also try running slightly thicker oil ONLY AFTER you fix the problem as described and degrease. For example if you run 5W30 or 5W40, be sure to take it up to 10W30, if you run 10W30, take it up to 10W40 for example. If you run fully synthetic, you should be able to take it up to 15w40 depending on your climate (should be fine in most cases). This can also help slow down your leaks, only after the problem is fixed of course. Good Luck!








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        Engine comaprtment covered in oil 700 1987

        I got out my bottle of Simple Green and got the engine cleaned up. I'll have my mechanic remove the throtle body and all the hoses and get them clean also. Where is the breather box and what does it look like? Is this the black plastic thingie/ accordion hose that hooks the throtle body to the air filter box?
        Also what does the "oil trap box" look like and where is it? I don't have a manual for this car so I have no reference material to look up.
        Thanks for your responses.
        Jorge








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          Engine comaprtment covered in oil 700 1987

          Jorge,

          I think there is a terminology issue here, breather box and oil trap box are one in the same. It will help you to look at the 700/900 FAQ section of the brick board (under features pull down list). Look under engine, flame trap and crank case ventilation.

          Gary







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