Thread: Oil from Turbo question

Dougal I don't understand how it could increase oil consumption when it is merely filtering out oil of the crank case gas produced. If you plumb it to return the filtered oil to the sump there would be zero oil consumption, on my engine I would be lucky to trap 50 mls between oil changes. On a friends TD5 its more like 250mls and he is going to change it to return to sump.

Chief is running a provent the equivalent of putting a chev into a Jag.

Originally Posted by two up

Dougal I don't understand how it could increase oil consumption when it is merely filtering out oil of the crank case gas produced. If you plumb it to return the filtered oil to the sump there would be zero oil consumption, on my engine I would be lucky to trap 50 mls between oil changes. On a friends TD5 its more like 250mls and he is going to change it to return to sump.

Have a read: http://www.aulro.com/afvb/isuzu-land...on-dr-ben.html

It appears the combination of the stock 4BD1T oil return and the volume of oil the 4BD1T passes through the factory seperator is more than a provent can cope with.

If you want to run a provent where there was previously an open vent, it'll be fine. But I replaced a factory air/oil seperator and quite simply the provent couldn't do the job.
I am convinced that a less bullet-proof engine than the 4BD1T wouldn't have survived being fed the volumes of oil mine was.

Changed the breather lines so that only the original was connected to the catch can. After a good drive there is far less oil in the catch can, which is a relief.

In conclusion the principles for stopping oil from crankcase through the breather are

- have catch can in highest spot.
- have crankcase breather in highest spot.

The breather I made on the inspection cover let more oil out than the original one despite the fact I made the fitting come out vertically and made the hose run vertical.

The run down the highway was tops, in 4th gear at 2500rpm and at about 90 to 100 clicks the turbo is whistling away and the car just wants to overtake everyone. Definitely worth the time and effort to do the turbo.