Thread: provent filter and another idea

cheers will have a look

Originally Posted by robbotd5

How many of you that have fitted ProVents to their TD5's have gone to the trouble of plumbing the oil return back into the turbo drain hose assembly? I have had my provent fitted for about 2000km's and the filter element is just on the point of saturation. I have a piece of clear hose fitted to the bottom of the provent with the check valve then to a steel plug that is held in place by its fit in the hose and a cable tie. I have had no oil in this tube as yet.
Thoughts?
Regards
Robbo

I assume the main point of the check valve is for running a closed system - i.e. where they may be pressure coming back into the provent from the outlet tube?

Originally Posted by feraldisco

I assume the main point of the check valve is for running a closed system - i.e. where they may be pressure coming back into the provent from the outlet tube?

The check valve is for return lines above oil level in the sump to stop venting directly from the sump which would go straight to the inlet unfiltered. It should allow flow from the filter drain to the sump and stop flow in reverse.

Cheers

Andrew


Sent from my mobile tellingbone using rock carvings.

What IS the recommended filter change interval for a PROVENT? I originally fitted mine, plumbed into the sump, with the air return to the inlet. I was having some trouble getting my VNT to run correctly, so whilst fault finding that, I unplumbed the air return, plugged the hole in the air inlet, and used a cheap crank case breather filter direct to the provent outlet. I would say that since I installed the provent, I have done maybe 5000km. The crank case breather filter is noticeably oily, and in fact, opening the bonnet after a big run, with the engine running, I can clearly see an oily haze emitting from the crankcase filter on the provent.

That says to me that the provent is now NOT WORKING.

Originally Posted by Hamish71

What IS the recommended filter change interval for a PROVENT? I originally fitted mine, plumbed into the sump, with the air return to the inlet. I was having some trouble getting my VNT to run correctly, so whilst fault finding that, I unplumbed the air return, plugged the hole in the air inlet, and used a cheap crank case breather filter direct to the provent outlet. I would say that since I installed the provent, I have done maybe 5000km. The crank case breather filter is noticeably oily, and in fact, opening the bonnet after a big run, with the engine running, I can clearly see an oily haze emitting from the crankcase filter on the provent.

That says to me that the provent is now NOT WORKING.

Sounds like yours isn't sealing, or you have damaged the element.

The provent should last >1500 HOURS.

It is possible to clean the filter (if you are careful and have an air compressor). Just place the provent element on a clean surface, and using an air gun, and a rag or a piece of styrofoam to seal around the air gun, blow compressed air down through the top and through the filter. You will see the oil bubble out.

This will temporarily increase the filtration efficiency of the element, until it reaches equilibrium saturation again. Eventually though, the element will clog with soot and need replacing, however that will take a while.

Don't use solvents to clean as you could damage the filter media or the glues retaining the media.

Thanks, can do that.

Can you describe symptoms/signs of the failures you mentioned?

Edit: actually, can you describe in more detail the cleaning process. Im having difficulty picturing it. I think you mean, remove the lid, and use something to seal around the ring, with the filter in place, and force air in there, causing oil to drip out of the drain. Is that correct?

Originally Posted by Hamish71

Thanks, can do that.

Can you describe symptoms/signs of the failures you mentioned?

You mean by blocking up with soot?

If the filter was getting completely clean oil, it would operate indefinitely and would never need replacing. However over time some of the soot in the oil will deposit in the filter and not come out with the draining oil. As this happens, the pressure drop across the element will increase (corresponding with a decrease in filtration efficiency (NOTE - UNLIKE dust/solid particle filters). However this process will be a gradual change. This will slowly increase until the pressure drop across the filter reaches 50 mBar under the highest blowby condition (max revs most likely), at which point the valve in the vent cap will open. Then it is most definitely time to change the filter.

Nope, not soot, I mean:

a. Not sealing properly?
b. element damage?
c. More infor on cleaning procedure.