740 oil leak

[Welldigger]

Hey guys,

I have a 740 with about 320k miles on it, and just yesterday I noticed some smoke coming from under the hood, as well as the smell of oil burning. So, I took a look. There seemed to be oil dripping onto the hot exhaust manifold. After some quick investigation, I found at least part of the problem.

The first image is of the general area the oil seems to be coming from (especially the bolt I have highlighted on the front of the mani.) I'm going to be tightening all of the bolts in the general area in hopes that that will at least slow the problem down. Judging by the splatter pattern on the rest of the engine, it seems to be leaking from the front, and then getting blown towards the back by the fan and dripping off of the circled bolt. There is also a possibility that some is coming from the plastic casing on the front of the engine.

The second image is to give you an idea of the quantity of oil that has accumulated on the engine from approximately 20 minutes of driving. I've only seen this much oil sprayed around once before, when I forgot to tighten the oil cap. I'm not going to pretend like I know a whole lot about the inner workings of my car... so the simpler any given explanations or suggestions can be, the better.

Thanks, guys!
-Matt

[russellengineering]

Hi Welldigger,

It looks like that oil is leaking out of the oil cap on top and dripping down.

Have you ever cleaned or replaced your flame trap and breather box? Your B230F engine uses a flame trap and breather box. The flame trap is nestled within intake manifold, near the fuel injectors. Your breather box is underneath the intake manifold. They both need to be cleaned or replaced because they will clog with oil vapors while doing their job. Your engine will not be able to relieve internal pressure, so it leaks through seals.

I would get the flame trap replaced, hoses cleaned out, and the breather box either cleaned or replaced. You could also probably replace your oil cap so you get a new seal up on top.

Detailed info on the maintenance can be found here http://www.brickboard.com/FAQ/700-900/E ... A_Treatise.

Those are my thoughts. Good luck.

Dave

[billofdurham]

I would start with the easiest and cheapest. Replace the seal in the filler cap.

Bill.