2008 BMW 750Li E66 CCV Replacement, Crank Case Ventilation Valve

5W40 2015-01-06 16:51:28 ( reads)

啥是CCV:

Crank Case Ventilation Valve (Crank Case Vent),Crankcase Vent (CCV),Oil Separator - The crankcase vent is an oil separator that ensures oil mist generated in the normal functioning of the engine finds its way from the top of the engine back to the oil sump.

CCV故障特征(摘抄)：

The CCV also has two failure modes. The most serious failure mode occurs during sub-freezing temperatures and is the result of a mixture of oil mist and condensate (water) combining and freezing the separator solid so it can't do it's job. In the other failure mode the integral diaphragm in the CCV cracks and creates both a vacuum leak and a path for oil vapor to be sucked into the intake manifold and later burned. The result is usually a rough running engine and lots of blue smoke billowing from the exhaust. If this occurs it will most likely be associated with a check engine light (CEL) due to the vacuum leak and misfires that are the result of the contaminated fuel mixture. In a worst case scenario, if sufficient oil is sucked into the manifold the result can be a hydrolocked engine and a very large repair bill. For this reason I believe replacement of the $80 CCV is cheap insurance while you are under the hood.

When a crankcase breather valve begins to fail, engine drivability suffers. You may have a rough idle, hard start or a check engine light that is ON with fuel trim faults. If your engine is consuming oil or smoking, checking the crankcase vent valve is a good place to start. The crankcase breather has also been known to emit a honking or wheezing sound from the engine when failing. It is mounted to the back of intake manifold, near firewall. The crankcase vent hose that runs from the valve cover to the crankcase breather valve is the hose I find broken the most.

保养车型及原因：

2008 BMW 750Li E66 80K公里， 90%是10-20公里以内的短途使用，每年一次机油更换（不按里程），目前车辆引擎运行状况良好。

去年9-10月份开始发现在低转速800-1000rpm之间有轻微不顺畅，当时怀疑可能是机油品质恶化，于是同年11月更换的原厂机油，经过几个月的使用，发现这种不顺畅只是变得更加轻微而不易察觉，但应该还是存在，于是判断应该和机油品质及机油运行相关部件（油泵除外）有关，而与机油运行相关的两个部件之一就是CCV，虽然也知道CCV失效的可能性很小，没有烧机油和怠速问题，但终究已经有7年多和8万公里没有检测过，所以还是买了备用配件，一般我的原则是既然都打开了就不想再把旧的装回去了，这样至少10万-8万公里以内没必要再担心这个部件了，也可以称作是预防性养护吧！

作案难易程度：1/5 (5为最困难）

起因的原帖：关于'2008 BMW 750Li (E66) 换油及入冬保养作业'的一点后记

说了废话一堆，还是看图吧！

4颗10mm螺帽，介个XX盖子就下来了，超级容易！