Ticking sound when started
 

If my 93 325is is started cold there is a bad ticking/clicking sound coming from the engine area that quickly goes away almost as if something in the engine wasn't lubricated (this is where it ticks) and then 5-10 seconds after start it goes away. Note: I put Castrol %50 Synthetic 10w-40 in sometime around the ticking sound began, obviosly noteworthy - could this be the cause? the oil weight shouldn't be a problem in the summer but I don't really know what I am talking about on that one. Any help would be greatly appreciated.

Ad Hoc, you helped me in another post and were very kind, I don't think that was fair or justified what MFDauto said in the other post. What kind of a human mocks anothers situation - it totally lacks honor, righteousness, justice, peace, love and anything that is good...thats for sure.

probably your valves and or lifters. Did you switch to synthetic ?? a little thinner oil would be better like 5w30 in my opinion. if you live in the desert area nevada, arizona thicker oil like that would be fine but 5w30 is a good all around oil

From a cold start it takes a few seconds for the engine oil pressure to build. During this time you may get valve ticking due to the lack of lubrication and pressure.

I have a broken backflow valve at the bottom of my oil filter housing in my "imaginary" M3 and it lets all the oil drain out of the housing when the engine is stopped.

Therefore my light stays on longer because the oil filter housing must refilll at every start. (This will also happen on the first startup after a filter change.) My car takes 6 seconds to build pressure from a cold start but a normal engine should only take about 3 seconds.

How long does the oil light stay on in your car during a COLD start up?

Did you make sure that the bottom o-ring on the cap bolt is in place properly? If not this could allow oil to drain from the housing.

10w40 in the summer is fine especially in warmer climates.

Thanks both of you for your wisdom

BMW recommends 15w-50 for warmer climates, or at least it does in my owners and service manual. I have a 95 325i and I use 15w-50 Mobil 1. It does great.

I too use 15w-50 Mobil 1 in summer, but mainly because I Autocross. If I wasn't Autocrossing I would use 10w40.

I would like to try 0w-40 Mobil 1 for winter if I can find it in a 5qt jug.

I just realized that in the original post haberman13 mentioned he was using Castrol 50% which I assume is a synthetic blend. I would not use a synthetic blend purely from a cost standpoint. You dont save enough buying the blend.

If you want to save money just use conventional oil and change more frequently. Or you can also blend your own (according to Shell) but you must stick with the same brand for both types.

Otherwise find a store that sells 5qt jugs of synthetic, like wal-mart, and you can get 5qts for $20.

Well, in the owners manual it says that 15w-50 is recommended from a little below 0 degress F and up from there. Since I live in a climate that almost never gets that cold, I use the 15w-50 all the time. I drive a lot, and I greatly rely on my car for work and school, so spending the extra money really doesn't bother me that much.

Most of my comments were refering to the orginal post. I certainly feel full synthetic is way to go.

As far as the vicosity issue, I prefer to change oil twice a year and I use a lighter oil with more modifiers in the winter. I want the oil to flow as quickly to the engine as possible during a cold start since the vast majority of wear occurs then.

Even though it doesn't get that cold here is Texas you are still approaching the recommeded low temperature envelope with a 15w oil.

Most new BMW's recomend 5w30 for all temperatures.

The BMW Service Information Bulletin S.I. 11 08 94 (4139) Dated Dec 1995 recommends:

Conventional Oils
15w40 for 5 degrees and up
10w-40 for 0-70
5w-30 for 50 degress and below

Synthetic Oils
10w-X for 0 and up
5w-X for all temperatures

Well, I have the same engine, and my oil hasn't given me any problems. The ticking noise is probably a cam follower that is blending down. I wouldn't really worry about it too much unless it's more of a knocking sound.