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View Full Version : Clicking sound from engine on cold weather



baksa
03-14-2006, 04:37 AM
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
11-01-2006, 09:27 PM
Anybody ever figure this out? I'm having the same problem. Or is it a problem?

CharlesAFerg
11-01-2006, 10:27 PM
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
11-01-2006, 10:32 PM
10-20 seconds is quite long.
I do not know that engines. Does it have hydraulic lifters?

rob101
11-01-2006, 10:50 PM
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
11-01-2006, 10:58 PM
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?method=show_fix&fixid=5

rob101
11-01-2006, 11:24 PM
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?method=show_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
11-01-2006, 11:25 PM
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
11-01-2006, 11:36 PM
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
11-01-2006, 11:40 PM
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.

NovceGuru
11-02-2006, 12:01 AM
Yeah, for the longest time i've considered one of these jobies: http://www.thinkauto.com/accumulators.htm

not necessarily from there but just the general concept of the oil pressure accumulator

NovceGuru
11-02-2006, 12:03 AM
Another link:

http://www.cantonracingproducts.com/accusump_purchase/accusumps.html

bsell
11-02-2006, 06:29 AM
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)?

If your oil is too heavy for the season, the oil can't get into the lifters immediately upon starting to take up the clearances in the lifters and prevent the clicking noise.

If your oil is correct for the temperature, your lifters could be dirty (and the rest of the engine!). Remember that the oil passages in a lifter are very small so any inordinate amount of buildup can slow oil pressure build-up in a lifter.

Big 'don't hold my liable' statement goes here.;)

An old shade tree trick to clean out engines is to pour in one quart of tranny fluid into the engine oil when it is hot, run it at idle for a couple minutes but DO NOT PUT ANY LOAD ON IT! That is right, leave it at idle or risk wiping your bearings out! The idea with this whole transmission oil deal is to use the high level of detergents in the tranny oil to clean out the lifter passages.

Of course there are commercial products to clean the internals of your engine and some work better than others. You might get by with something like this. Or it might just go away after whatever is blocking the oil passages gets moved out of the way without any help from you.

After 'cleaning' the engine, change the oil and filter using the proper weight oil for the temperature.

Brian

Ferret
11-02-2006, 07:52 AM
When was the last time your oil was changed?

I always find with mine that you can tell when a change is due up - cams start rattling - mind you I tend to use crap oil because I go through so much of it lol.