Engine Rattle when Warming Up - Diagnosis? ?

Alex Funnell

Alex Funnell

Dedicated Member
British Zeds
Joined
Feb 11, 2015
Points
38
Location
Warwick
Model of Z
Z3
Hi guys,
As I said in my intro thread I have a loud vibration/rattle noise I hear when it is warming up. It doesn't do it when it is stone cold but in between. It then goes away once it is warmed up and only occurs around 1500 rpm. See the video below. I was leaving the office so it's not in the engine bay but you can hear it.


I think it may be the chain tensioner not getting enough oil pressure. I hope it's not the vanos or a pump bearing.

I'll try get a better video when I have time
 
Last edited:
Alex Funnell said:
I'll try get a better video when I have time
Click to expand...
That would help, I can hear the rattle with a decent set of headphones on but have no idea what it is. Not sure if anyone else can make it out though!
 
Can't tell from video but you should be able to home in on a more specific area using a `listening stick' - a long handled screw driver will suffice - just put the blade on different components and your ear to the handle - obviously take care with moving parts.
 
Must admit that was my initial thoughts. I hope not.
 
Do you have good history of oil and filter changes? I would be tempted to put some flush in it and run that till hot and change oil and filter.

Tony.
 
I'm not sure, the previous owner had all service history apart from the one before I owned it and did 6000 miles per yr. I soon as I bought it october 2014 I did a full service and put Castrol Magnetec 10W40 A3/B4 oil in. I have just serviced it again in october and have put castrol magnetec 5w30 c3 this time. The noise certainly has got worse since I have owned it, however I didn't check if the engine was warm when I bought it - my mistake
 
I had strange rattle that turned out to be a loose spark plug.
The plastic covers on top of the engine mask the sound so whip those off to help you hear better.
 
I did change the plugs on my first service, i'm fairly sure I torqued them all. I will check. It does sound like something rattling against plastic.

Also it did start miss firing when I went up high altitude hence this picture. We had to stop due to the smell of fuel.

Europe Road Trip

Europe Road Trip

Misfiring at high altitude

Or it miss fires if I literally run the engine 30 seconds then next time I start.

Definitely worth a check.
 
Another worth while thing to do is remove the auxiliary belt and run it without .

Tony.
 
On my first service I did replace the aux belt, tensioner and the water pump for the metal bladed one. I will try the belt removal as well.

We must remember it only makes the noise between warm and running temp. See the first vid temp gauge. It only just started doing it
 
Use the screwdriver Alex, Find a long screwdriver, place the tip against various parts of the engine and hold your ear against the handle. By moving around the engine from front to back, top to bottom, you should soon be able to pinpoint the source of the rattle. You will be amazed at how clear the movements of the engine appear using this method. Once you have done that you should be able to determine what is wrong. If you can't, tell us exactly where the sound is coming from and I'm sure someone will come up with the answer. Above all be objective, it is easy to make yourself believe that a noise in the engine is a terminal issue, hopefully it will be something simple. But every thing is repairable it really depends how much effort and cost it takes to put right.

Mike
 
EnthuZiaZT said:
Use the screwdriver Alex, Find a long screwdriver, place the tip against various parts of the engine and hold your ear against the handle.................................

Mike
Click to expand...

Agree Mike - I did suggest this yesterday evening - the old fashioned methods are sometimes the best in these situations.
 
The trouble is Colin @jonco these days people have to rely too much on computers to locate a fault. But he fact remains, however high tech engines get they still rely on the 4 stroke cycle. Suck,squeeze, bang, blow and all the basic auxiliary items which drive the ancillaries. Many of which you can "hear" through a screw driver or similar listening tool.

Tony.
 
try valve life cleaner its poss one or more of your valve lifter sticking not getting filled with oil, this will clean them out when ready for next oil change put some cleaner in before you change the oil this works for a lot of cars
 
However many electronic gizmos they put on an engine, it is still an engine working on the same principals as the first engines ever built.

Mike
 
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