pcv valve - does the WH CRD have one

[fester]

Pretty much all modern vehicles would have a PVC system. On the 2.7 it's a big disk moulded into an asymmetrical block that bolts on top of the rocker cover so it may not look like you expect. I think the 2.7 one can be pulled off and cleaned so likely yours can too. The Provent has a pressure relief valve built into it do it's not a likely suspect. Hose could be dodgy but not sure how much pressure goes through the system and whether is blows out more so than gets sucked out even though it plumbs back into the inlet. The Provent is not full at all is it, do you have it draining back into sump. If swirl motor was playing up you'd have a fault code registered and most likely the mil light illuminated. I don't think the swirl flaps playing up could cause a pressurizing of the crankcase. Default position for the flaps unpowered is fully open and if they were jammed shut they only block half the inlet tract and at worst cause rough running and drop in power. They can leak out the pivot point if worn badly.
I would think offhand the main culprits to crankcase pressure would be malfunctioning Pcv or worst case excessive blowby in which case you'd be down on power

What did you use for hoses to connect the Provent up and silly question is it hooked up the right way.

[ginga]

Thanks Fester
Provent has been installed for over 2 years so doubt there is a problem with hoses as they have springs around them to stop them from 'kinking' & are shielded by thermal 'paper'.
Motor sounds fine & there aren't any apparent loss of power.
Problem only happens at highish speeds when accelerating.
The search goes on

[ginga]

An update

Problem appears to be the hose from the Provent to the turbo side - 'collapses when under extreme pressure & returns to normal appearance when cool! Provent itself activates the valve when the outlet pipe is blocked so crankcase gasses etc have nowhere to go!

That's despite hose being encased in a spring & then wrapped in heat resistant foil.

Suggestions on a better hose type appreciated.

[drover]

Hydraulic hose shouldn't collapse under suction and is good for heat and oil but only likes very slight curves. Have used some on my system and heater hose from engine to can. Hoses that can have suction applied or a curve usually have the spring inside to stop collapse, fitted outside is for chaff protection.

[fester]

External spring is mostly used to help a hose hold a curve but doesn't do anything to stop it collapsing. Also if the bend is too tight it won't totally stop it kinking on the inside bend. If you need a really tight bend your only optiuon is a formed hose or a hard line (steel/stainless/aluminium/copper) to form the bent section you need then connected with short bits of hose.

What sort of hose did you use, was it oil tolerant. It might be that it was OK originally but now if broken down a bit with the oil it is now softer and not able to maintain form. Any fuel hose or hydraulic hose should be stable with the oil but at the size of the provent fittings will not take kindly to too much of a bend.

Have you compared your layout to others that have posted pics here to see if there is a better way to route the hoses to reduce the amount of bend.

[roscoea26]

ginger,

Have you checked the filter in the provent? I was thinking perhaps it may be blocked with too much oil and not allowing a free flow of gas thereby building up pressure in the crankcase. Just a thought.

[multihull]

On your other thread on the same subject I was going to ask if you have a stock engine system or have you fitted a Provent. Seeing you have a Provent fitted you may have a blocked or kinked pipe or they're connect back the front or maybe it's time to change your Provent filter. Check the pipes and then remove the filter for a trial run and this may solve the problem if it does by a new filter.