Author Topic: 1991 318is M42, loud clicking  (Read 13299 times)

josephb983

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1991 318is M42, loud clicking
« Reply #30 on: March 11, 2008, 09:55:42 PM »
I just ran the video of the cold engine next to the video of the warmed up engine, and it helped me pinpoint the noises. I still don't know for sure what is causing them though.

Cold:
http://s271.photobucket.com/albums/jj142/josephb983/?action=view¤t=MVI_6899.flv

Warmed up:
http://s271.photobucket.com/albums/jj142/josephb983/?action=view¤t=MVI_7041.flv

nomad

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1991 318is M42, loud clicking
« Reply #31 on: March 11, 2008, 10:06:02 PM »
cold vs warm would tell me it could be related to oil temps.

louder at certain rpm ranges indicates something that is rattling or loose. The frequency of the rattling object (chain slapping?) will match up with the frequency of the engine only at certain speeds.

Still sounds like chain issue to me.
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nicknikolovski

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1991 318is M42, loud clicking
« Reply #32 on: March 12, 2008, 03:19:13 AM »
Remove your upper & lower timing covers, take some photos of the timing assembly and post on here. This may seem like a dumb idea but you never no - maybe you should check the actual engine timing as well. Could the engine be out of timing slightly causing a diesel type engine noise. I don't think this is the problem however might be worth a go.

josephb983

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1991 318is M42, loud clicking
« Reply #33 on: March 12, 2008, 03:34:45 AM »
Quote from: nicknikolovski;44622
Remove your upper & lower timing covers, take some photos of the timing assembly and post on here. This may seem like a dumb idea but you never no - maybe you should check the actual engine timing as well. Could the engine be out of timing slightly causing a diesel type engine noise. I don't think this is the problem however might be worth a go.

Can M42's get out of timing? I thought it did it automatically.

nicknikolovski

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1991 318is M42, loud clicking
« Reply #34 on: March 12, 2008, 06:04:27 AM »
I don't mean the ignition timing (this is ECU controlled), i mean the actual camshaft timing. When you rotate the crank to TDC for cyl 1, do the cam gears line up at TDC as well?

Could the timing chain be a tooth out maybe?

Also, if you remove your timing covers, you can have a look for any broken or damaged components. I would just do the entire timing chain assembly. I seen a 92 Mercedes SL500 with a chain that broke. It got caught under one of the guides and then seized the motor. $$$$$ damage. Cars are funny things, and anything can happen.

bmwpower

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1991 318is M42, loud clicking
« Reply #35 on: March 12, 2008, 06:10:21 AM »
When you pulled the chunks out of the oil pan, was there anything blocking the pickup?

Timing *looks* to be okay from the gear picts.

nomad

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1991 318is M42, loud clicking
« Reply #36 on: March 12, 2008, 08:19:10 AM »
What do your plugs look like?
check connections on your plug wires too. far fetched but I'm wondering if it could be a weak spark or a cylinder missing.

It really sounds like something mechanical though. The timing gears look to be in the right "centered" position too.
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josephb983

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1991 318is M42, loud clicking
« Reply #37 on: March 12, 2008, 11:30:23 AM »
Quote from: bmwpower;44630
When you pulled the chunks out of the oil pan, was there anything blocking the pickup?

Timing *looks* to be okay from the gear picts.

There was a bolt in the pan, from the upper pan. I screwed it back where it belonged. It didn't improve the noise though.

How oil pan looked:
http://i271.photobucket.com/albums/jj142/josephb983/1437546b.jpg

josephb983

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1991 318is M42, loud clicking
« Reply #38 on: March 12, 2008, 11:34:05 AM »
Quote from: nomad;44633
What do your plugs look like?
check connections on your plug wires too. far fetched but I'm wondering if it could be a weak spark or a cylinder missing.

It really sounds like something mechanical though. The timing gears look to be in the right "centered" position too.


Wouldn't a weak spark plug cause rough idle? The idle is very uniform, just it is loud like a diesel.

bmwpower

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1991 318is M42, loud clicking
« Reply #39 on: March 12, 2008, 01:05:58 PM »
It's definitely a metallic sound, so I wouldn't guess it has anything to do with the spark plugs.

Have you checked all of the guides?  You gotta pull the whole timing cover to see them all.

It almost sounds like the chain is riding on something metal.

And if there are bits of what appear to be old chain in the pan, I'm guessing the previous owner either broke a chain or something else in the valve train.  Which makes me suspicious of the condition of the valves and everything else.  Why someone would not take the time to drop the lower pan after a chain disintegrated, I have no idea.  Worries me that's all I'm saying.

Hate to say it, but it sounds like something bad...almost like a bent valve.  Do a quick compression test.

shutter

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1991 318is M42, loud clicking
« Reply #40 on: March 12, 2008, 06:15:19 PM »
I just picture a chain when I listen to those vids.  It sounds bumpy, like a chain, if that makes sense.  But that's listening to a video over the intra-webs.  

The previous poster speaks wisdom.  Do a compression test, then do the steps to get your timing covers off.  Post pics when you do ;)
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