Hi Guys
This post is more of a fishing post as well as a help post. Last week I replaced my rad and refilled the system but still have a leak somewhere. Engine isn't holding pressure over night like it should so have a leak. I don't have overheating or over pressure so don't think I have a HGF. Started doing a bit of a search on the BMW forums as it's Beemer engine thought those guys would have more knowledge. As it turns out they have directed me to a leak on the Valley pan. I had noticed some coolant at the back of engine last week but didn't have a clue where it was coming from. It turns out BMW V block engines have suffered from this problem for a long time due to poor design of the seal on the valley pan. This also sits well with my car being 80k miles new and a common issue of the age. What I've found is alot of poor idle and running problems have come from air leaks within the inlet system. To do the valley pan the inlet system needs removing so when replaced using new gaskets problems with air leaks are sorted. I've found a great how to page for a 5'series Beemer but most parts are relevant to us. If you have poor running hopefully it will help and if you have both coolant loss and poor idle it's a winner!
I plan on doing the valley pan in the next few weeks to hopefully finally cure my coolant loss. Hopefully this will be the Holly Grail to my loss.

http://members.cox.net/rlacm/IntakeIndex.htm

There is loads out there on this issue but doesn't seem to have been cover here yet.
Rob

you're having a pain with that problem mate , hope it gets sorted soon.. ... - .- -.




Y. O. L. O.
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No so much of a problem as I'm quite happy topping up the coolant it's just in the back of my mind the dreaded HGF will appear or the engine will explode in a cloud of smoke oneday. Probably paranoia but just a niggle I want sorted. It's bad enough with owning a RR without one causing headaches. Lol

There's some good info on that BMW page.

I'll check mine later today for signs of leaking coolant just incase.

ALthough I'm not loosing water, I'm failry sure I have a vacuum leak somewhere as I do have a poor idle and vacuum related error codes

I might need to bite the bullet and get this sorted. I'm normally a "have a go joe" but in this instance I think it's a mechanic job looking at how complicated that looks.

Thanks!

D 

To be fair Dan if you happy with a spanner and have the time i would give it a go. There is nothing complicated there just time consuming! I'm planning a weekend job they say 5-6 hours but think thats for someone whos done it before. A weekend to take time and make sure everything is clean should be enough. The tools used are standard and nothing special so would deffinatly have a bash. Whats the worst that can happen .
If you want more detailed stuff for our engine google M62 4.4 valley pan. I found loads of pics and bit part explinations that combined with the how to ive posted should make things easier. We dont have cable acceleraters and idle valves but im sure we have other trickery and witchcraft to give us a curve ball.
I had to get ontop of the engine and look down the rear left behind the square bit on the back of the plenum. I could only see a small area of the top of the Valley pan but there was a good pool of orange goo so must have had the leak for a bit i think.
From google there is quite a big issue with these leaking. I hadnt heard anything obout it untill i got on the BMW forums.
Also from the forums they recomend changing the waterpump as the coolant side is in bits. Prob not a bad idea if it hasnt been done reacently or have a pump with plastic impella.