BMW X5 CCV

[RFaber]

Sniffer, when i lived up north, we used our dogsleds to get around! (or our skidoos!) I feel your pain but short trips kill just about any vehicle! (see previous dog sled reference!!) My X isnt a garage queen, and i suspect that a CVV re and re is in my near future, none of the tan mayo just yet, but it hasnt been changed in any of the service records, and I have a valve cover gasket, and oil filter housing gasket to do soon, so i can keep more oil in the engine!
JCL, how does one go about cleaning the CVV?? what chemicals Dont deteriorate the diaphram? and should i pull out the dipstick tube and clean it too??? what is the annual servicing you speak of??

[JCL]

Originally Posted by RFaber

JCL, how does one go about cleaning the CVV?? what chemicals Dont deteriorate the diaphram? and should i pull out the dipstick tube and clean it too??? what is the annual servicing you speak of??

Each of the CCV systems is slightly different by engine model and year. Some models had a kit available from BMW with a replacement diaphragm as a service part.

I would inspect all of the lines, and replace any that are soft. The valve is straightforward to replace. The engine valve cover could be removed and cleaned of any condensate. I wouldn't replace the dip stick tube, but rather check that it isn't plugged.

I wouldn't use any harsh chemicals. The system normally sees oil mist, so a solvent or diesel wouldn't be any harder on it than its normal environment. I would check the system, and then look at it the following year and see if there was any buildup (if the vehicle had the same sort of use that year). If there wasn't any, I would go several more years before checking it again. If it was plugged, I would check it more often.

PCV valves used to be a regularly replaced item at an annual tune up, back in the day. This system is just a complicated PCV valve.

[Ricky Bobby]

Originally Posted by JCL

PCV valves used to be a regularly replaced item at an annual tune up, back in the day. This system is just a complicated PCV valve.

I'm sure most people forget this the most, and I'm glad you brought it up Jeff. However, the PCV valves replaced annually on domestic vehicles, etc is about a 5 dollar part and 10 mins of work to do so.

The CCV is definitely more complicated with its placement etc on the E53, but I still think it should be a routine maintenance item, as hoses might leak, crack etc with age, and any dried up gunk or buildup in the CCV should be cleaned out, one could clean the CCV and hoses annually, as you mentioned, but since its a tedious process, I don't think many would do it.

Personally, I am thinking about doing the CCV and hoses as a preventative maintenance interval. I have 71,000 miles now, perhaps by 75k I will replace it and the hoses, as they are 10 years old, and I would probably do it in another 75k as an interval.

I drive my X mostly highway and avoid short stop/starts and trips in the winter time, so I have not had problems with condensate to note in my 2 years of ownership. Not sure if the PO ever had an issue before me, but I do note that the CCV hose I can see, is not insulated cold climate version, so I assume the system is original.

[flatlander]

There is usually quite a few CCV and Oil Separator problems in the winters for the 8 cylinder M52 models. I've had the problem before twice in one winter.

The first time I had the system freeze up, I had the Oil Separator replaced. Then a few weeks later there was another freeze up and oil loss, so I had to look into it further. It was then I discovered that there are more parts and oil passages that must be considered when addressing this problem. The rear diaphram on the intake manifold is the CCV diaphram and it can fail and freeze. There are several hoses and metal tubes which must be cleaned out or replaced since oil mist passes through them and it may freeze.

The heated wrap may also be purchased. It is installed around the two vent rubber hoses to keep them from freezing. This kit was quoted to me at around $800 from the local BMW shop. I did not buy it.

There is also an alternative oil dipstick tube which was developed to address possible freezing in the dipstick tube. I did not purchase this either, as I had no condensation in the dipstick tube.

I've attached a couple of diagrams which show the primary parts and passages that are involved in this system working properly.

I hope this helps. Even though I do this annual maintenance, I tend not to drive my E53 in the coldest part of the winter just to avoid the possibility that the system freezes up. The consequences of this system freezing up are too much to deal with, so I drive my other car in the coldest of the winter.

[JCL]

Originally Posted by Ricky Bobby

I drive my X mostly highway and avoid short stop/starts and trips in the winter time, so I have not had problems with condensate to note in my 2 years of ownership.

The condensate isn't a cold weather issue, it can form all year in most climates. It is just that it freezes in the winter. If it freezes when parked, it doesn't matter how long your drive is, it can cause problems before it thaws out.

Just pointing out that the focus on the cold is only relevant to dealing with the symptoms of the condensate forming, not the formation of it.

I do recall PCV valves costing around $5. Sparkplugs used to cost the same. If I add up the maintenance cost for 100,000 km with each of my last four BMWs, it is much lower than I used to spend on maintenance parts in older vehicles.