My engine started leaking a lot of oil yesterday when i made a 850 mile trip. Before yesterday, the oil level didn't change noticably between oil changes, it may have had a slight leak but nothing to worry about. But yesterday, it lost more than a quart of oil (over 850 miles) and when parked after I arrived I could see a lot of oil under the car. I am not totally sure, but i think it is coming from the rear of the cam shaft. It also seems to be leaking slightly from the oil fill cap onto the cam cover. The front seals are fine, and i canged the rear main seal when i replaced the clutch less than a year ago. It seems strage to me that it would change that quickly. Is it common for this seal to fail in this way???

Thanks, Mark

Had an oil sensor(down by the oil filter) go bad/cracked. The oil appeared to be comming from the rear of the engine, it would blow down while driving. Do the flame trap regardless, and replace the oil cap gasket and maybe pick up a spare, had one go on the highway and it wasn't pretty. good luck

The other posts forgot to mention why your rear cam cap may have blown out.

The cause of 'leakage' around your oil fill cap and blown rear cam seal caps is usually a plugged flame arrestor. The tubing and oil droplet separator below the flame arrestor can also become plugged up.

You could also have more serious problems that caused an increase in blowby and a corresponding increase in crankcase air pressure.

It's hard to get that hole clean and dry enough so that the cap won't immediately blow out again. There are a couple of small threaded holes on the back of the head. You can make a small retainer bar and bolt it over the cap, or the volvo parts online stores will sell you a fabricated retainer and bolts as a kit.

You can also try securing the cap with some oil-resistant sealant, preferably O2 sensor safe sealant.

If that plug blows out, it's a big 2" HOLE in the back end of the head. Replace it immediately and don't drive the car till it's fixed! It's possible it could catch fire due to so much oil pouring onto the hot exhaust manifold.

The plug is dirt cheap, $2 or something. You need the round one, not the half-moon in case they ask. You CAN install it without taking anything out, but it's difficult access. You may want to buy a new valve cover gasket at the same time, and remove the valve cover so you can see what you're doing with the plug.

When mine blew out on my old 87, I heard a THUNK against the firewall like I'd kicked up a rock...
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Rob Bareiss, New London CT ::: '87 244DL/M47- 234K, '82 245T/M46-182K, '84 242DL/AW70-100K, '89 244DL/AW70- 212K and I miss my: 86 244DL 215K, 87 244DL 239K, 88 744GLE 233K, 88 244GL 147K, 91 244 183K

Check the rear cam plug - it's at the rear of the head. Stick your hand back there and see if you can feel the end of the camshaft - if so the plug has jumped ship. It is famous for blowing out, especially when crankcase pressures are high due to clogged flame trap/breather box.

See this picture of the plug, and measurements for a retainer you can make.
http://www.brickboard.com/RWD/index.htm?id=741835
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85 245 DL - 91 Mazda MX6 Turbo