Is it worth it to Clean the CCV valve?

[brokenbmx06]

There has to be an easier way... Could I just run some Seafom through it to rinse it out then change my oil?

[ArmyX5]

Originally Posted by LeiZ

Hey ArmyX5,

What's the size of the tubing you used? I'm thinking of doing it myself these days. 2 years ago my X caught on fire due to frozen CCV, and I've spent over $1,500 to replace all the hoses. Yesterday I saw the yellow milky stuff again, so I can't wait to dig you post out.

Thx, bro.

LeiZ,

I am sorry, but I cannot remember the size of the tubing. I am going to do this maintenance very soon and need to get the tubing again. Will let you know as soon as I get the new tubing.

[JCL]

Originally Posted by brokenbmx06

There has to be an easier way... Could I just run some Seafom through it to rinse it out then change my oil?

No. You can try and clean out the engine with a product like Seafoam, but it is hard on the engine. Just do a hot oil change. Seafoam does nothing to the CCV since oil doesn't circulate through the CCV.

[upallnight]

Don't ever recall this being a problem on my E34, but then it didn't have the CCV like the M54.

[theblue]

that milky stuff is normal and gets burned off... cleaning it out is pointless because it will return pretty quickly and is never really harmful to begin with.

[JCL]

Originally Posted by theblue

that milky stuff is normal and gets burned off... cleaning it out is pointless because it will return pretty quickly and is never really harmful to begin with.

It is really harmful if enough of it collects in the CCV and then freezes.

[theblue]

it's not the same stuff collecting... it's getting burnt off.

[FCBuff]

Originally Posted by theblue

that milky stuff is normal and gets burned off... cleaning it out is pointless because it will return pretty quickly and is never really harmful to begin with.

I disagree. If CCV is working, there should not be any Mayo under the fill cap. I had the mayo until I replaced the CCV, now nothing, and no oil consumption either!

[JCL]

Originally Posted by FCBuff

I disagree. If CCV is working, there should not be any Mayo under the fill cap. I had the mayo until I replaced the CCV, now nothing, and no oil consumption either!

It is the other way around. The condensate paste is formed over time from the engine not getting hot enough, and being kept hot long enough, to burn off the moisture that is in the engine. The moisture emulsifies with the oil, forms the paste, and if it is collecting under the filler cap (easy to see it there) it will also collect elsewhere. If it collects in the CCV, and it gets cold enough, it can freeze.

The CCV doesn't cause the paste, it is a victim of the paste freezing. The CCV can work perfectly and the paste still collect. If it doesn, the fault is the driver's, for abusing the vehicle with too many short trips and never giving it a good hot run.

You are correct that there shouldn't be any paste under the filler cap. It should never form, because the moisture should be burned off first. Once it has formed, it doesn't easily burn off.

[FCBuff]

Originally Posted by JCL

It is the other way around. The condensate paste is formed over time from the engine not getting hot enough, and being kept hot long enough, to burn off the moisture that is in the engine. The moisture emulsifies with the oil, forms the paste, and if it is collecting under the filler cap (easy to see it there) it will also collect elsewhere. If it collects in the CCV, and it gets cold enough, it can freeze.

The CCV doesn't cause the paste, it is a victim of the paste freezing. The CCV can work perfectly and the paste still collect. If it doesn, the fault is the driver's, for abusing the vehicle with too many short trips and never giving it a good hot run.

You are correct that there shouldn't be any paste under the filler cap. It should never form, because the moisture should be burned off first. Once it has formed, it doesn't easily burn off.

I here you, that is the conventional wisdom.

However, I will tell you that I know all of that and have observed that, having just replaced the CCV this fall, there is no Mayo under the fill cap after short trips. Likewise there is no longer any significant oil loss. I drive it 300miles round trip skiing weekly, but often lots of short trips in between. It reached a point where it did not matter if I drove it for a long drive or not, there was always mayo. I never had the mayo before, and all of a sudden it started. I also have driven multiple cars with similar driving and never have I seen "mayo" formation, this includes 3 other BMW's. It seems to be unique to the M54 I don't pretend to completely understand it, but replacing the CCV solved it! Hopefully for a good long time too, since I don't want to have to replace it again anytime soon!