Thread: TD5 Air Induction Pipe Replacement?

Stepping it is probably not the best option as you need a smooth transition into the turbo inlet. A stepped intake will create turbulent flow affecting the overall performance.
You may need to have a custom sheet rolled and welded conically to keep the existing profile.

The elbow is a diaphragm valve. Don't remove it, modify it to fit back in. It only opens at certain vacuum rates to let crank venting thru.
Take this out and you will get too much drawing from the crankcase.
Cheers

Andrew

Originally Posted by LOVEMYRANGIE

The elbow is a diaphragm valve. Don't remove it, modify it to fit back in. It only opens at certain vacuum rates to let crank venting thru.
Take this out and you will get too much drawing from the crankcase.

Thanks Andrew, thats logically kind of what I suspected. I had thought of putting a check valve in there, but I wouldnt know the value required.

As for the turbulence....yes, but it cant be much worse than the inside of that corrogate rubber piece? In trying to find the parts I need, Im thinking it would now be, preferably, getting an exhaust shop to bend me a piece of 76mm (3in tube), which hopefully they can flare to 80mm for the MAF end, and then using a 76mm to 60mm reducer at the turbo end....or, as you suggest, for a little more outlay, I could have a metal reducing element welded on, keeping the surfaces smooth.

Originally Posted by LOVEMYRANGIE

The elbow is a diaphragm valve. Don't remove it, modify it to fit back in. It only opens at certain vacuum rates to let crank venting thru.
Take this out and you will get too much drawing from the crankcase.
Cheers

Andrew

Confused?

If I understand correctly we’re talking about the crank case vent pipe which connects to the turbo air intake which provides suction pressure as the air intake flow increases.

Now I have a 2001 build TD5 defender which I gather will have the same plumbing in this regard.

If the angle pipe into the air intake has a valve which only operates when sufficient vacuum is supplied by the air intake how is pressure relieved when there isn’t sufficient pressure to operate the valve?

Originally Posted by scott oz

Confused?

If I understand correctly we’re talking about the crank case vent pipe which connects to the turbo air intake which provides suction pressure as the air intake flow increases.

Now I have a 2001 build TD5 defender which I gather will have the same plumbing in this regard.

If the angle pipe into the air intake has a valve which only operates when sufficient vacuum is supplied by the air intake how is pressure relieved when there isn’t sufficient pressure to operate the valve?

Should probably correct myself a tad. Its not vacuum that opens it, its the crank pressure. But vacuum plays a part in not allowing it to open excessively. Its more like a differential release valve.
There is a spring that keeps the diaphragm seated, opening under crank pressure. Vacuum at low speed is not enough to suck it closed so it will vent as much as the spring load on the diaphragm will allow according to its rating.
Once engine speed increases, so does crank venting volume however the increasing vacuum from the turbo intake reduces the rate of diaphragm lift regulating the crank venting amount.

If you take it off, you can blow through it at the inlet but you cant suck through it on the outlet.

From what i could see in mine last time I looked at it, it also has a small hole at the bottom between the two chambers allowing it to drain oil to the outlet. I had my tube off to patch the tear in the spigot for the valve only to find the inside of the convolutions filled with oil and a trickle from it running into the turbo! Explains why the intercooler outlet hose is wet.
Also noted that its wetter since bypassing the EGR.

I am looking at other types of catch cans rather than just the ProVent. I do think its a very good product, but its size and material means sacrificing dual battery space and an aluminium one could be made to tolerate exhaust manifold heat and mount closer to rocker cover outlet.
I have a couple of things in mind but no equipment or experience to make one or two and try them.

Cheers

Andrew

Lovemyrange,

Keep us all posed on the catch can. I've got the provent and size is and issue. Having said that at present I'm just venting mine straight out.

"Seems" to have made a difference but most likely the placebo effect. Having had the radiator intercooler and inlet manifold all cleaned I feel better knowing that as far as possible only clean cold air is going in.

Will do. Just need someone to take sketches to product.

I have a few ideas, all designed to be removable and cleanable and without the need for tapping into the turbo oil return hose.

I have a mate who is a boilermaker, just need to make time to sit down and start working on it.

Cheers

Andrew