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Old 07-04-2011, 02:38 PM
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doru doru is offline
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Location: Calgary
Join Date: Sep 2007
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Mein Auto: 2003 530iA
Originally Posted by nyclad View Post
Excellent DIY Doru!

A few questions:
Did you need to replace the gasket?
Just curious, do you think the job could be done outside of an oil change? Or does the oil need to be drained to do this DIY? (I plan on doing it during the oil change anyways.)
You need to replace the gasket - it's an aluminum crush washer. Cost is below 1 $. Probably the oil is already in the sump, I did it when I changed the oil because it made more sense to me.

Originally Posted by bluebee View Post
I still haven't fixed my windshield washer fluid 'cuz 'that' job even scares me!

But, reading the details, I agree - it doesn't seem all that hard (unless something goes wrong - and - with me - something 'always' seems to go wrong).

So, the real question is ... how badly can I screw this one up!

Back on topic - I see you made a case for changing it. Do I understand correctly the intention is to prevent the rail guides from failing?

Are the rail guides plastic? Why would they fail if the chain tension is off? Is it because the chain slaps against the rail guides?

Is 'that' what makes the noise you said is no longer being made?

Why would simply changing the spring change noise otherwise?
Pay attention when taking off the cylinder head (the 32mm "bolt") - it is tight, and you don't want to hit anything with the wrench. When I took it off, and also when I torqued it back, you have the secondary air hose in the way - pay extra attention NOT to lean on it. Also, there is the air check valve, try not to hit it.

I believe the compression of the spring will induce a slap, which is heard as a chain rattle. When the chain is loose, it's harder on the chain guides. Also, a loose chain will elongate faster.

In "my case" the noise went away,and if you look at the pic where the 2 springs are side by side, it's not a big difference in length, but obviously that's what it took to take the noise away. I used the same oil brand (GC 0w-30) so, that's the only change I made.

By changing the spring, you restore the OEM tension on the rails, which in turn will tighten the chain - no more play. The more compressed (shorter) the spring is, I believe the noisier the rattle is. Which in turn will probably shorten even more the lifespan of the chain guides. I have no idea if they are teflon coated or not (like the v8).
Looking for a DIY? Parts? Check this out, it might be your ticket

Stable: e92is, e46, , e83, f25, e53 - sold, e39 RIP

Last edited by doru; 07-04-2011 at 02:39 PM.
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