Cold morning starts

[Vicbitter]

Hi all,
On these cold winter morning startups, the diesel would emit a slight bottom end tap/knock until the engine warms up. Just confirming its normal and just being paranoid, haven't had a diesel in years.
Cheers.

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[GHendo]

My NP Di-D doesn’t normally do that – the only time I’ve heard it do it, was after I changed the oil and didn’t fill the new oil filter with oil before I installed it. Might be a good idea to check the engine oil level and possibly the type of oil you have in there. It sounds like the oil is not immediately being picked up by the pump.

Cheers

Geoff

[Vicbitter]

Oil levels are fine, and it does sound like the oil isn't being picked up immediately.
But being from the bottom end, wouldn't this be the case if it was on the top end?

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[Vicbitter]

Coming from the top end, just takes a while for the oil to reach/warm up.
Might have to do an oil change.

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[DINKY]

Vicbitter mine does same thing, after having a 1HDFTE for 14 years this is not normal for me, but a few minutes later noise goes away. Just had 1500k check done nothing noted from Mits

[spot01]

I've had 5 CRD Gen 4 (NT to NX) and they vary a bit from car to car.

A couple (including my new NX) are a bit more "knocky" when cold than the others, so it appears to be normal, although a bit variable between cars. It goes away when warm.

I only notice it outside the car, not inside.

BTW, in general terms, the NX is definitely quieter inside than the earlier models.

[Vicbitter]

I've had 5 CRD Gen 4 (NT to NX) and they vary a bit from car to car.

A couple (including my new NX) are a bit more "knocky" when cold than the others, so it appears to be normal, although a bit variable between cars. It goes away when warm.

I only notice it outside the car, not inside.

BTW, in general terms, the NX is definitely quieter inside than the earlier models.

Yeah, no noise inside, guess it's injector knock, but the sound definitely goes away when warm.

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[insect_eater]

is injector knock the only cause of clanking

guess it's injector knock, but the sound definitely goes away when warm

My NX clanks when cold much more than my NW did, even after fresh oil. I can hear it inside and outside the car, and only goes away when the engine is fully warm (ie. after driving for 10-15 mins, and the ultragauge shows 86C). A slight single loose tappet noise remains when warm.

MM detected no unusual noises when booked in for a check, when they did a small quantity learn procedure, and an oil change at my request. It seemed quieter for a while after this, but didn't go away.

If it goes away when warm, and shows no knocking under load when warm, is it safe to assume it is just injectors?

If so, do you fix it, or just live with it?

[Vicbitter]

If it goes away when warm, and shows no knocking under load when warm, is it safe to assume it is just injectors?

If so, do you fix it, or just live with it?

No knocking when warm, just on start up. Just was a little paranoid as I had a v8 before the Pajero, used to knock a bit and the knock was the lifters failing. Which eventually did

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[_jp_]

Would you be able to detect the noise on a video? Maybe you could take one on your phone and upload it.

[Kumabear]

Mine used to make a bit of a clatter on start up as well. Its not happened since I swapped to a 5w-40 oil. (not going to open that can of worms) just stating what resolved it for me.

Costs a little more but It turns over a littler easier in the morning and is smoother once shes fired up.


(below is not really related to your problem)
If it has been really cold that night/morning I also tend to double glow the plugs seems to help as far as getting it to start nicely as while its never failed to get going if its really cold <4c in the morning it can tend to sound like a 60 year old smoker trying to clear their lungs lol.

[littleriver]

Mine used to make a bit of a clatter on start up as well. Its not happened since I swapped to a 5w-40 oil. (not going to open that can of worms) just stating what resolved it for me.

Costs a little more but It turns over a littler easier in the morning and is smoother once shes fired up.


(below is not really related to your problem)
If it has been really cold that night/morning I also tend to double glow the plugs seems to help as far as getting it to start nicely as while its never failed to get going if its really cold <4c in the morning it can tend to sound like a 60 year old smoker trying to clear their lungs lol.

x2 on above ...

I waited 30 seconds before I went to start the Car the other day ... it helped a lot (started first go) ....
also using the 5w 40 full Syn ... (but it when it's on special) ...



...

[insect_eater]

Unable to upload .wav files?

I do have some recordings, but as far as I can tell, .wav files are not an allowable type of file for attachments (not in list / upload fails)??

[insect_eater]

Its not happened since I swapped to a 5w-40 oil. l.

I also changed to 5W-40 Synpower, and it did improve things. This morning was 13C, and there was little clatter, maybe I need to move to a warmer climate...

[insect_eater]

sounds files loaded - appreciate people's thoughts

Would you be able to detect the noise on a video? Maybe you could take one on your phone and upload it.

I have loaded some sound files on google drive, and I understand that they can be downloaded via this shared link:

https://drive.google.com/open?id=0B7KiqN5vG6xNenpIWHNXTmlFUjg

EDIT: I'm particularly interested in what you think about the particular single cylinder knock that can be heard, rather than the general level of clatter

There is one where the engine is warm, the rest are cold starts. The warm one provides a good reference of how I believe a normal 4M41 sounds. Maybe listen to it first and last. The first file (10 degrees cold 2.wav) shows the clanking pretty consistently, but less when revved.

Sometimes it starts with a few seconds knock, then settles to a fainter knock. Half way through the sound files, I rev the engine to 1500, and in some of these the knock becomes very apparent.

In one file, the engine was slow to start because I missed to glow plugs turning on the recorder. In this file I moved the recorder around a bit, which probably gives a misleading impression that the sound fluctuates in and out.

Overall the range of files picks up the knock in different forms. I would describe it like a small end knock or a hydraulic lifter failure. When I am 30m away, it is the only distinctive sound that I can hear from the car - one cylinder clanking. My NW never made such a sound.

This only occurs on cold mornings, above 13C, it only has a faint knock that quickly blends in with the normal diesel clatter.