Clicking sound from engine on cold weather

[baksa]

Some days ago, when it was really cold (around -8 to - 13 degrees C), when I started my 1992. 520i 24v, I got loud clicking sound from engine bay, which lasted 10-20 secs, and then stoped.
Now, when it's warmer outside, it doesn't happen, and engine sounds normally from start and through the ride.
I suppose that noise is coming from the valves, but could it point to some malfunction or that is normal on very low outside temps (note - my car stays outside, I don't have a garage)?

[Macv]

Anybody ever figure this out? I'm having the same problem. Or is it a problem?

[CharlesAFerg]

thought it was just valve ticking. I know you can reduce it with a certain type of lubircant, it was discussed very recently i believe... Wish I could help you more, but I think it's just normal for the most part. The only sound my engine makes that's pissing the hell out of me is a squeaky alternator or pump or something by the radiator, it's a really scratchy squeak, what should I look at first?

[shogun]

10-20 seconds is quite long.
I do not know that engines. Does it have hydraulic lifters?

[rob101]

10-20 seconds is quite long.
I do not know that engines. Does it have hydraulic lifters?

yes they do, its just the m50 (surely you must be slightly familar with them? otherwise you disappoint me Mr. Erich: Guru of all things bmw related)

[shogun]

Have there been any cases with lose banjo bolts on this engine like on the M30?
Or did you hear that there were problems with the oil reservoir where the small ball in the reservoir got smaller and the oil went down instead of beling ready to supply immy oil? Is the low oil pressure light on when starting?
examples only
http://www.nmia.com/~dgnrg/banjo.htm
http://www.e32fixes.com/results.asp?...ow_fix&fixid=5

[rob101]

Have there been any cases with lose banjo bolts on this engine like on the M30?
Or did you hear that there were problems with the oil reservoir where the small ball in the reservoir got smaller and the oil went down instead of beling ready to supply immy oil? Is the low oil pressure light on when starting?
examples only
http://www.nmia.com/~dgnrg/banjo.htm
http://www.e32fixes.com/results.asp?...ow_fix&fixid=5

nah nothing like that, however there can be cases of the bolts for the oil pump backing themselves off. and oil pump gaskets failing and causing foaming in the oil. but this happening only when the engine is cold suggests worn lifters. Some people suggest a molydenum disulphate oil additive is good for that, personally i don't worry about it too much, but then again my engine is approaching 260 000 km and it'll be time for a rebuild/replacement engine soon.

[rob101]

oh yeah check your oil level if its too low or too high it can cause this (too low starvation, too high crank foams the oil)

[NovceGuru]

I've always been told it's because the hydraulic lifters haven't come up to pressure yet, allowing a small gap between the cam lobes/valves. AFAIK (which isn't much!)

NovceGuru

[rob101]

I've always been told it's because the hydraulic lifters haven't come up to pressure yet, allowing a small gap between the cam lobes/valves. AFAIK (which isn't much!)

NovceGuru

it is my friend but oil pressure is the major cause of that, besides the lifters wearing out and losing the ability to retain hydraulic (ie engine oil) pressure.