Given my old girl has done 170k and seems to be having more turbo related issued (limp home 3 or 4 times per 60 mile trip), I have decided that I need to address the matter.

The plan is:

- replace all the small bore vacuum hoses [some of these have worn on various clips around the engine bay]

- vent the crankcase breather to atmosphere (cheap!) [to prevent more cr@p entering the system]

- blank off the EGR (maybe) [to prevent more cr@p entering the system]

- clean the EGR (again) [to clear out the current oily build up]

- clean the inlet manifold [to clear out the current oily build up - never been done]

- take off the turbo and clean up the vanes

Therefore to proceed with step 1 I need to know the internal diameter of the vacuum hoses running around between the n75, turbo, etc.

Also if there any reason why some of the hoses have a fabric outer?

Can the hose to the vacuum ball/reservoir be pulled off at the ball end? Or will I need to cut the pipe off and join it?

Where should I get the hose from? Motor factors (have a unipart place just down the road), or pick some up from ebay? Not looking for any fancy colours, just some black would be fine to match the oil burners fumes

Thanks.

Edited 8 September, 201015 yr by mbames

I'm looking to replace the vacuum pipework as well and am unsure of the size required, will probably remove and measure to confirm, I'm going to get it from here......

http://www.beal.org.uk/hoses-tubing-fittings/tubing-hoses/cat_36.html

Rather than strip the turbo to clean it I'm going to give this a try, £29.82 +vat..............

http://innotecworld.com/c-1064-turbo-clean-set.aspx

Edited 8 September, 201015 yr by alexandjen

I assume this might be the puppy:

http://www.beal.org.uk/hoses-tubing-fittings/tubing-hoses/advance/retard-rubber-tube-1/8-10m-/prod_1077.html

I might check using my new Aldi digital calipers...

oog, that turbo cleaner thing might be worth a short first. I am getting more and more annoyed with mine, especially as it keeps doing it mid overtake, it could potentially turn an overtake into a dangerous activity.

There are two sizes 3.5x2 (N 0203535) and 5.0x3 (N 0202821). IIRC, dealer prices are not to bad (especially if they will sell it by the metre).

A Mityvac is extremely useful when diagnosing this kind of fault.

Sticky vanes is the most likely cause of your problem but it's not the only cause. A few things to check before pulling out the turbo.

1. The N75 (Charge pressure control) and N18 (EGR) are changeover valves. If you imagine a straightforward open/close valve, it wouldn't work as when the valve was closed, the capsule would still contain a vacuum and wouldn't move back. The changeover valve allows air into the capsule when valve turns off, allowing it to move back. This is why there are three pipes attached to the valves. The 'extra air' tube is fed from the air filter housing. It is not uncommon for the fitting to get broken off when changing the air filter. If this tube gets blocked it can disrupt the operation of the turbo so make sure it's still attached to the airbox.

2. Depending on the exact date of manufacture, there are variations to the vacuum layout. In one layout, there is a non-return valve between the N75/vacuum reservoir and the rest of system. If this is failing it can cause turbo problems

I have a spare EGR blanking plate and gasket if you need one.

Have fun

Thanks for the size details. My car seems to have a strange pipework arrangement, for instance the lower left vacuum hose from the n75 is one of the larger size, but after about 1 1/2 inches is then joined into a small piece of pipework (which then goes down to the turbo). I might give my local dealer a call and see what pricing they can give me (or maybe see if a mechanic out the back will give me a few metres :yes: )

I have a black and white thing installed in some of my pipework....

So that maybe a non-return valve.

I have in the past changed both the n75 (dealer supplied part) and the black one to its left (obtained from a scrap yard)

I have noticed, but never been 100% on this, that if I take off the return pipe to the airfilter housing and blow/suck down it, the car seems a little more responsive the next time I drive it (never know if this is in my mind or not.....)

The spare EGR blanking plate and gasket would be handy, sure I could exchange a beer voucher or two :-)

Right.... Mityvac who has one, and knows how to use it, and is prepared to help me....

when your stripping and cleaning you might consider doing the intercooler at the same time, as it is the low point in the system you can get quite a bit of oil in there which doesn't help airflow

when your stripping and cleaning you might consider doing the intercooler at the same time, as it is the low point in the system you can get quite a bit of oil in there which doesn't help airflow

That is probably were my 2litres/year ends up

Cambelt is due in another 10k, so I might take the IC off then. The only snag is that someone's previous cack-handedness has broken the release tab on loom plug for the drives side headlight bulb assembly, thus making it hard to undo some of the IC pipework

Edited 8 September, 201015 yr by mbames