Replacing the PCV Valve and thats when it went a bit wrong....!!!

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Yep, my car is also LPG, so plenty of pipes��
Going to order all the bits and pieces next week inc the PCV.
Then have set aside next weekend to do the job....on the condition that I take her to her mother's this weekend�� that will be fun....��

Will you be around next weekend for some tech advise, should I need it?

only to point and laugh as we share your misery
 
Is what we are here for...moral support and endless pee taking (you must have noticed this about LZ by now...the advice and help is second to none....but the general banter and micky taking is paramount and unrivalled!)

Absolutely....wouldn't have it any other way😜
Looking forward to taking **** myself when I'm 'experienced' enough😛😛
 
Just a quick update based on about 10 mins sitting in the car looking at cd changer leads with the engine running. My idle has gone down to around 500 rpm. It was definitely more than this before the PCV was changed, around 7/800. Anyone else had this as a result?
 
Hope it's OK to add to this post, another top job from Saint.

I am looking for reasons to not do this job as even just having a look at mine gave me the arse and this 'how to' doesn't look fun either.

I have a 2004 4.4, 115 K.

I had an issue earlier this year of a couple of the spark plug bores filling with oil causing a misfire and also I have oil weeping from the front of the Cam Covers. I have ordered the Cam Cover seals including the rubber washers but even though when the transmission was out we replaced the soggy dissolved breather pipes to the PCV Valve and separator, I decided not to replace the PCV Valve while we were there as I didn't realise what a common problem they are.

I have read that leaking Cam Covers can be a symptom of a faulty PCV system however as usual my vehicle is not straight forward in the way that my PCV Valve doesn't have the two top pipes connected, shown in the pic below, but have been blanked off with what looks like factory caps, as I saw in RSW Solutions video, he had one of them blanked off. I am guessing its something to do with my missing SAI.

I have no idle or running issues, my idle is 450 rpm and steady as a rock and I don't see any smoke from my exhaust but wondered if there is another way of testing the valve or what other symptoms I could look out for.

I have seen on a youtube video of somebody with a BMW simply removing the diaphragm, spring and cap and replacing that with one removed from the new unit which took about 10 minutes but the cap looks different to mine.

I am also aware of the fact that if a jobs worth doing its worth doing properly but also that if it isn't broke don't fix it..

Just looking for advice really, i have a transfer box rebuild scheduled for my Christmas holiday, oil and filter change, the Cam Cover seals and possibly the front suspension arms and CV joints so I am not looking for extra work if its not necessary.

These are the pipes I have missing.

90.jpg

This is a very short and shaky video of my PCV valve, the two yellow clips are where the blanking caps are.

http://vid51.photobucket.com/albums/f383/holidaychicken/PCV%20VID_zpsh1wte6o9.mp4.

Stop whining and get on with it is a valid reply :)
 
Short answer is yes. Operation of the Pcv valve can be tested with a slack gauge manometer attached to the oil filler when the engine is running. You should see a vacuum registering. I can't remember the figures quoted or even if it's callled that but if you go that route I will sift through my info for some hard details.
 
I did reply this morning but my post was either removed or in rushing out to work I had only looked at the preview and didn't actually reply. I am sure somebody would have said if it was removed so here goes again.

Thanks for the info, in searching for your terms used I found a very useful BMW site with loads of info regarding checking the PCV system and also a PDF which I have uploaded so hopefully it's ok to link to this site.

There is a simple test of holding a piece of plastic over the dipstick or filler cap to see if you get some vacuum indicated and also a simple method of making the slack tube manometer you mentioned.

I also wondered if there was any reading that could be checked using Faultmate that indicates crankcase vacuum so I'll have a search for that.

Stand by for an update

Thanks

How to test the BMW E39 pressure-controlled crankcase ventilation system (CCV)? - Bimmerfest - BMW Forums

CHECK PCV1.jpg

CHECK PCV2.jpg
 
Hi Andy,

If your hoses are bad, the PCV will no doubt be a little lacklustre too!

The job is relatively simple, the bugger bits are the access to the Torx bolts (and trying not to round them off - unless some other numpty has been there beforehand and fecked them for you) and the little pipe that is unseen under the right hand (as you look at the car from the front) cylinder head!

The rest was simple....just remember to check that the little rubber grommet is on the old PCV valve before you try and fit the new one.....I didn't check and I tried to push the new PCV valve on to the pipe with two gromets and the pipe snapped!

Other than that it is just lying on top of the engine and getting intimate with it!

As for the Faultmate....there is no pressure sensor in the oil sump that I know of!
 
Cheers Ant, my hoses are all good as we replaced those but when Jason said "you should really look at changing that PCV valve" i said " nar, fudge it, that looks alright":eek:

I did a quick test as to how much Vacuum was present at the Dip stick and Oil Filler cap, i couldn't actually get the filler cap off as it was sucking so hard, and she is sucking like a ................(insert own metaphor).

I may knock up a manometer but I am thinking it must need doing as I couldn't find any receipt in the folder of history I have and as the pipes were totally shot, at 115K it must be forked.

My cam cover seals are definitely leaking, but tell me why if the engine is sucking should oil be leaking out or am i getting confused with the PCV system blocking up and causing excessive pressure and my seals are just knackered ?:confused:
 
Try taking the dipstick out...you should hear a faint gurgling sound....withdraw the dipstick and start to place your thumb over the hole, if you can hear air rushing past your thumb or you feel a strong vacuum, then the PCV is defo fecked....there should be a tiny vauum, that can just be felt...anymore and the PCV is leaking.

The PCV valve sits on the back of the intake manifold and regulates the crankcase pressure via a diaphragm, if this diaphragm splits, then you get manifold vacuum into the sump.

Explained nicely here... Timm's BMW M60, M62 and M62TUB V8 Engines - PCV and OSV
 
Nice link, your write up on changing is better though.
I held a piece of cling film over the dipstick hole and it didn't exactly get sucked down the bore although there was a definite suction.

If the diaphragm spring regulates the vacuum pressure, would the value remain the same even at higher revs?

The car was cold so still on a faster idle so i will test again when I have more time.
The one thing that concerns me is that the two upper inlets on the PCV valve, the two with yellow retainers, are capped off on mine ? Any ideas ?

I am going to make a manometer just because I have some clear tube and it would be interesting to see the actual value I have, providing it doesn't just suck all the water into the oil..
 
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Nice link, your write up on changing is better though.
I held a piece of cling film over the dipstick hole and it didn't exactly get sucked down the bore although there was a definite suction.

If the diaphragm spring regulates the vacuum pressure, would the value remain the same even at higher revs?

The car was cold so still on a faster idle so i will test again when I have more time.
The one thing that concerns me is that the two upper inlets on the PCV valve, the two with yellow retainers, are capped off on mine ? Any ideas ?

I am going to make a manometer just because I have some clear tube and it would be interesting to see the actual value I have, providing it doesn't just suck all the water into the oil..
Use Engine Oil....Oil and Water weigh roughly the same (we all know oil floats on water as it is less dense and lighter - but only by fractions!)

That way if there is plenty of vacuum, then it will only be ingesting oil and not water!
 
Bit of an update, and hopefully ok to tag onto your thread Ant, on testing my PCV, not got around to changing the Cam Cover seals yet but did test the PCV following the procedure below.

CHECK PCV1.jpg

CHECK PCV2.jpg


First job was to make a Manometer.
I ordered a new oil filler cap so I could attach a pipe connector. I already had the hose and the connector from an earlier experiment on bleeding the coolant system straight back into the header tank but that's another story.

I drilled a smaller hole all the way through and then gradually drilled larger holes in the outside until the M10 thread on the connector self tapped into the plastic, I added an O ring for good measure.

IMG_3525.JPG

IMG_3524.JPG

I had a piece of white kitchen board left over from a kitchen project and some white pipe clips from when I plumbed in my fridge so I attached the pipe to the board.

I added some engine oil, following Saint's advice, in case my PCV was shot as in the test procedure it says it could show excessive vacuum if the diaphragm is faulty and could suck the fluid straight into the engine.

Engine off OIL.JPG

I connected the manometer to the engine with the modified filler cap.

IMG_3518.JPG

I marked on the board the level position and then started the engine which I had previously warmed up and turned off all ancillaries.
I marked the low and high points and then measured the distance between the two.

IMG_3515.JPG

I repeated for water with some red dye added and measured the same.
Now I think this is because of different densities, or my error, but the oil measured around 140 mm and the water was around 100 - 120, but both within the 3 - 6 " specification mentioned in the instructions.

IMG_3523.JPG

So according to this my PCV should be ok and as I don’t have any other symptoms I am not rushing to change it although as I already have the new part and a trick little ratchet 1/4 hex bit driver to get access to the torx bolts I will do it at some point...maybe :)

IMG_3541.JPG

Sealey Stubby 1/4" Hex Screwdriver Bit Holder Stainless Ratchet/Wrench AK6962 | eBay
 
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