DSM's NEVER make bad sounds...

[CamWeiss]

I'm dailying the car right now, and want to address a few issues that I've been ignoring.

It's making a god awful sound from the motor right now... Hoping for a hand or some ideas to diagnose it and a few other things as I get to them.

As background, I don't recall how long it's been doing this for - I haven't been driving it much this year - but it is slowly getting worse. I thought at first it was a noisy lifter (it's got those too sometimes, I should probably do the revised lifter update at some point). It's clearly not. It's bad when the car is cold, and it fades away when it's hot. It's dependent on RPM - It's noisy as hell till it hits ~2500 rpm, and then silences completely. When the car is up to temperature, it'll occasionally kick in and out, but it's not as loud.

Here's a couple of videos. The first one is a cold start, yesterday morning. You can hear as I bring it up past 2500 rpm and it disappears.
http://youtu.be/24L4Vkj08ro

The second video is when the car is mostly warmed up (~180 deg). You can hear it fade out and then come back at one point - It's not the movement of the camera causing the noise fluctuation.
http://youtu.be/aMWUZwuwZ0Q


Thanks for the help, guys. Hope this one isn't too serious.

[Brett Haviland]

sounds like ur timing belt tensioner.  definatly get it fixed asap!!!  if the belt slips that could spell the end of that engine

[CamWeiss]

Anyone want to second that?

Hell... I know it's approaching time for a belt job anyways (it's got 88k on a Dayco kit, back before I knew any better). I was hoping to put if off for another couple months, and do a bunch of seals on that end of the motor as well.

Any other possible causes?

(ps, thanks Brett)

[Brett Haviland]

other causes??   well could be alot of things...  maybe a balance shaft bearing has gone bad and the balance shaft is flapping around in the block... but i had that happen and it didnt sound that bad.  The only time i had a similar noise was when i had a bad tensioner... it wasnt as loud as yours... but sorta sounded the same.

other possible causes...

ac/alt/p/s stuff loose?  it definalty sounds like a metalic rapping noise... and definalty not like a lifter noise... more sounds like a rod knock noise, but it going away and comming back like that would be typical of the timing belt flapping and tensioning up at certain RPM ranges.

[Remi Raymond]

I agree with brett, that sounds like someone is holding a baseball card on the cam gears - it has to be something on the timing side of the engine. I wouldn't drive that until you get it solved!

[Jordan Kruger]

totally the tensioner     the engine runs smoother when warm,   as a result there is less change in speed of the timing belt. It will hold a nice steady rpm and keep enough tension on the belt to shut it up a little.   Once the rev drops a little the tapping will come back ( due to the belt getting slack )    I wouldnt even start this engine again until this is fixed either.   It could be as simple as the tensioner pulley centerbolt being loose.   then again,  its a sound clip... could be anything

[CamWeiss]

My ignorant ass has been driving it for a while like this... I guess it'll have to make one more trip into town tomorrow to insure the other car.

fracking DSM. I ran out of patience for this car a while ago. I'm practically writing up the FS post in my mind now.


Thanks for the help guys! Will take the (Upper?) cover off and poke around with a stethoscope to confirm. Then, I guess it's time for a TB job. Yay?

[Remi Raymond]

Well before you hate on it to much, when was the timing last serviced? Not knocking you, you're a smart guy but if its overdue, its overdue.

[CamWeiss]

Not quite due. 88k since the last job - Timing belt, balance shaft belt, water pump, pulleys, tensioners.

If I have to get in there, I might as well do another TB job. I'd rather not spend the money right now!
I see that RTM has balance shaft elimination kits. They're cheaper than buying a new balance belt and tensioner.

https://www.rtmracing.com/xcart/product.php?productid=17355&cat=1386&page=1

Are there more parts/machining needed for the BS elimination?

[Brett Haviland]

hahah but the labour to do the b-shaft delete is like more then the labour to do the timing belt !!

[Tony Leong]

hahah but the labour to do the b-shaft delete is like more then the labour to do the timing belt !!

2nd agreement here.

[Shane Sawatzki]

88K on a dayco belt... to me would be way overdue. I ran a couple dayco belts and I changed them at 50k each time lol. You should pop the upper timing cover off, only a couple 10mm bolts and inspect the belt. Are you still living in crystal view? my gf lives like 5 houses away from where you live (or lived if youve moved) I could stop by anytime if you need a hand with it

[demetrios aftias]

My buddy has this same problem let me know how it works out for you.

[Chad Giffen]

I would never push a timing belt over 70,000km. They only take 1 afternoon to swap out and it's just such an insurance policy on your engine. Why wait?

[CamWeiss]

Car's sitting in the driveway, have the BMW insured now.


Shane - I moved in April. West Saanich/Keating area now. Much better! I looked at the belt a week ago, and rotated it through with the starter. Looked, surprisingly, fine. There is a small oil leak on that end of the motor somewhere, but the belt isn't wet.

I had our parts guy call up Lordco, Beck Arnley water pump and ContiTech TB kit available. I know the B-A stuff is often repacked OEM, can anyone speak to the ContiTech belt and kit? I'm going to call another supplier tomorrow and see what they're carrying.
OEM is a bit pricey for me at this point... I know it's the preferred route.