Technical 2007 Fiat Ducato 3.0 oil change and suspected clogged oil breather filter

[panutt]

I changed the engine oil and filter yesterday. For the first time I discovered the used engine oil to come out with a "clunk, clunk, clunk" as no air was able to come in to the engine. I had not loosened filler cap. Is this normal? Should´nt the oil breather let the air into the engine? Is there any intervals of changing oil breather filter?
And then, when finishing the oil change, I started the engine without the filler cap, and I think it was a lot of air pressure coming out of the filler hole. Engine has 60.000 km after total overhaul. Some thoughts and knowledge, anyone?

 

[Greasytrucker]

I think you’re looking for problems where there might not be any. Was the oil warm when you changed it? If not it often comes out in glugs regardless of caps off etc. As regards to running the engine with the filler cap off, it’s not good practice to do so, filler caps are quite often part of the engine breathing system so running them with it off often makes them run rough. And yes i’ve had many a vehicle where if you do take the cap off whilst running there is pressure there. As long as it’s not blowing oil anywhere it shouldn’t be e.g into the air filter, or excessive amounts in the turbo pipe work i wouldn’t be overly concerned. Obviously I’m talking generally about engines here, someone on here with the same engine may be able to give you some comparisons with there’s

 

[Communicator]

On my 2.8jtd the blow by gases pass through the oil vapour separator, before being connected into the air inlet via a non return valve {NRV). I think that the 3 litre engine has a similar return for the gases, With the oil filler cap in place, there is no obvious air inlet to the sump. Hence glugging is to be expected.

For more detailed information see pages 35 & 36 of the X250 Training Manual for the 3 litre engine, which is available in the Downloade section of the forum. (The shorter file relates to the 3 litre engine.)