Cold start rattle 2-3 seconds then gone.

[ac427]

If the rattle goes once the vanos is up to pressure. What would that indicate?

[sapote]

If the rattle goes once the vanos is up to pressure. What would that indicate?

probably the worn down plastic check valve in the oil filter housing leaking, drained all the oil to the pan after a long night. People had successfully replaced this value with aftermarket part.

[ac427]

probably the worn down plastic check valve in the oil filter housing leaking, drained all the oil to the pan after a long night. People had successfully replaced this value with aftermarket part.

Thanks. Would that be a VAC Motorsport part or another supplier?

I looked at the VAC part and it appears to open the flow to the oil cooler permanently. I'm not sure if a check valve is involved.

[sapote]

Thanks. Would that be a VAC Motorsport part or another supplier?

I looked at the VAC part and it appears to open the flow to the oil cooler permanently. I'm not sure if a check valve is involved.

post the link to the part and I will take a look. Don't remember who sold the part but maybe on ebay.

[ac427]

post the link to the part and I will take a look. Don't remember who sold the part but maybe on ebay.

This is what i was looking at

https://store.vacmotorsports.com/mobile/vac-motorsports-oil-diverter-valve-bmw-s50b32s54-p4056.aspx

[sapote]

This is what i was looking at

https://store.vacmotorsports.com/mob...s54-p4056.aspx

No, this is the oil distribution slide valve.
This is the one I'm talking about:

Edited: I was looking at the wrong part, not the anti-drain check valve. The check valve is at the bottom of the filter can where the pump pushing the oil in. I don't know if the valve is serviceable but you can try to flush to clean its sealing seat. To check if the valve is leaking, park the car overnight then remove the filter lid and see if all outside of the filter had drained off.

[ac427]

Thanks.

From the E46 Complete Vehicle doc: "Oil Cooler (flow controlled by 95ºC thermostat in oil filter housing)"

I presume this valve has nothing to do with temperature control and is just a check valve to ensure oil is available at startup?

[r3_galek]

Hi,

Appears I have a similar issue I think, i've only owned the car for 8 months or so, i've not got any history on previous work done to it. Got the same issue where only on cold start it seems to have this rattle, when it idles after cold start i can't hear any knocking from the bottom end, last time i changed the filter I couldn't see any metal shavings.

I have got a brand new beisan vanos, the upgraded oil pump disc and the sprocket hub, new tensioner, upper chain guide, vanos accumulator, valve adjustment has been done.

Just want to check if there's anything else worth trying, before doing the big job? Has the oil filter housing replacement worked for anyone else?

I am planning to do the rod bearings as I have no history so better safe than sorry, going to go down the acl + arp bolts route as that seems to be the most popular route.

Thanks

https://youtube.com/shorts/Wxvf77n4Q10?si=NtTBBPebm91DQTOo

In person it sounds very much like andrews issue below, so that makes me believe it might be the rod bearings.

https://www.youtube.com/watch?v=P3O5iGn9tMg

[ac427]

Hi,

Appears I have a similar issue I think, i've only owned the car for 8 months or so, i've not got any history on previous work done to it. Got the same issue where only on cold start it seems to have this rattle, when it idles after cold start i can't hear any knocking from the bottom end, last time i changed the filter I couldn't see any metal shavings.

I have got a brand new beisan vanos, the upgraded oil pump disc and the sprocket hub, new tensioner, upper chain guide, vanos accumulator, valve adjustment has been done.

Just want to check if there's anything else worth trying, before doing the big job? Has the oil filter housing replacement worked for anyone else?

I am planning to do the rod bearings as I have no history so better safe than sorry, going to go down the acl + arp bolts route as that seems to be the most popular route.

Thanks

https://youtube.com/shorts/Wxvf77n4Q10?si=NtTBBPebm91DQTOo

In person it sounds very much like andrews issue below, so that makes me believe it might be the rod bearings.

https://www.youtube.com/watch?v=P3O5iGn9tMg

I'm going to do an oil analysis which should indicate if thd bearings are worn.

I'll also look at replacing the timing chain tensioner.

If that doesn't fix it it's time to replace the oil filter housing.

[sapote]

If that doesn't fix it it's time to replace the oil filter housing.

If the oil inside the filter can didn't drain out overnight then it's not the root cause.

[ac427]

If the oil inside the filter can didn't drain out overnight then it's not the root cause.

True. I put it as the third option. It would be hard to tell because as soon as you remove the OFH cap it will drain into the sump or not if already empty.

[jayjaya29]

True. I put it as the third option. It would be hard to tell because as soon as you remove the OFH cap it will drain into the sump or not if already empty.

You can tell by how quickly the oil light goes out when starting the car up after letting it sit. I really don't think theres anything wrong with your OFH.

[ac427]

You can tell by how quickly the oil light goes out when starting the car up after letting it sit. I really don't think theres anything wrong with your OFH.

I think you are right. How many seconds after ignition should the oil light stay on roughly?

My startup is sometimes accompanied by a screech, which is worrying. I thought it might be a bearing but it's very intermittent. Perhaps one in ten starts.

Perhaps the startup rattle is coming from the timing chain tensioner.
They seem really simple devices though. What actually goes wrong with them?

[sapote]

Perhaps the startup rattle is coming from the timing chain tensioner.
They seem really simple devices though. What actually goes wrong with them?

the tensioner should have a check valve to prevent oil drain out with engine off. If it drained then....your noise.

[r3_galek]

I don't think this is tensioner related, I believe i have the same rattle, rebuilt the vanos, replaced the tensioner with a brand new one from BMW, chain guide from beisan and it still persists.