Rattling noise on shutdown - ZR-1 Net Registry Forums

DaveK · 09-20-2010

Over the last week or so I have noticed I sometimes have a kind of 'rattling' noise when I switch off the ignition. It's not always there and definitely is after the engine has stopped. Sounds a bit like a piece of wood rattling around somewhere.

I've done a visual inspection and see nothing obvious. The sound seems to come from the very front of the engine bay so I am thinking it's probably a cooling fan bearing or similar on the way out? If that's the case how am I fixed for a replacement fan?

Anyone have any other ideas of what it might be?

Thanks

Scrrem · 09-20-2010

Quote:

Originally Posted by DaveK

Over the last week or so I have noticed I sometimes have a kind of 'rattling' noise when I switch off the ignition. It's not always there and definitely is after the engine has stopped. Sounds a bit like a piece of wood rattling around somewhere.

I've done a visual inspection and see nothing obvious. The sound seems to come from the very front of the engine bay so I am thinking it's probably a cooling fan bearing or similar on the way out? If that's the case how am I fixed for a replacement fan?

Anyone have any other ideas of what it might be?

Thanks

It could be your dual mass fly wheel dampers going bad. How many miles on the car?
Rich

DaveK · 09-20-2010

Thanks Rich. 100,000 km/60,000 miles.

Wouldn't the flywheel damper sound more as if it were inside the cockpit or close to the bulkhead?

Scrrem · 09-20-2010

Quote:

Originally Posted by DaveK

Thanks Rich. 100,000 km/60,000 miles.

Wouldn't the flywheel damper sound more as if it were inside the cockpit or close to the bulkhead?

Sorry Dave, I should have read you post more carefully

I suppose it could be the cooling fan bearing. Have you checked your idler pulley? I had a strange knocking sound that my 90 made with the enging running. It ended up being a water pump bearing. I never heard a water pump bearing knock like this one did.
Rich

DaveK · 09-20-2010

I'll check it but this is happening after the engine has stopped so I don't think the idler or water pump would be still turning.

Thanks!

Ccmano · 09-20-2010

Dual-mass flywheel... mine does it too. If you ever watch closely at the moment when an engine comes to a stop, the piston compression causes it to come to an abrupt stop or even a slight backwards rotation. This causes the flywheel to occilate a few times if the damper mechanism is shot. BTW mine has 61K miles on it. Seems to work fine otherwise. I'm just waiting for more of a reason before I go to all the work of dropping the trans to replace the flywheel and clutch. I have a low mile D/M flywheel sitting on my work bench waiting to that day.
H

09-20-2010	#1
DaveK Join Date: Jul 2004 Location: Sudbury, Ontario. Canada Posts: 1,538	Rattling noise on shutdown Over the last week or so I have noticed I sometimes have a kind of 'rattling' noise when I switch off the ignition. It's not always there and definitely is after the engine has stopped. Sounds a bit like a piece of wood rattling around somewhere. I've done a visual inspection and see nothing obvious. The sound seems to come from the very front of the engine bay so I am thinking it's probably a cooling fan bearing or similar on the way out? If that's the case how am I fixed for a replacement fan? Anyone have any other ideas of what it might be? Thanks __________________ 1991 #1516 Black/Black davidmkelly.com "Speed is often confused with insight." - Johan Cruijff

09-20-2010	#3
DaveK Join Date: Jul 2004 Location: Sudbury, Ontario. Canada Posts: 1,538	Re: Rattling noise on shutdown Thanks Rich. 100,000 km/60,000 miles. Wouldn't the flywheel damper sound more as if it were inside the cockpit or close to the bulkhead? __________________ 1991 #1516 Black/Black davidmkelly.com "Speed is often confused with insight." - Johan Cruijff

09-20-2010	#5
DaveK Join Date: Jul 2004 Location: Sudbury, Ontario. Canada Posts: 1,538	Re: Rattling noise on shutdown I'll check it but this is happening after the engine has stopped so I don't think the idler or water pump would be still turning. Thanks! __________________ 1991 #1516 Black/Black davidmkelly.com "Speed is often confused with insight." - Johan Cruijff

09-20-2010	#6
Ccmano Join Date: Jun 2006 Location: Sparks, NV Posts: 2,852	Re: Rattling noise on shutdown Dual-mass flywheel... mine does it too. If you ever watch closely at the moment when an engine comes to a stop, the piston compression causes it to come to an abrupt stop or even a slight backwards rotation. This causes the flywheel to occilate a few times if the damper mechanism is shot. BTW mine has 61K miles on it. Seems to work fine otherwise. I'm just waiting for more of a reason before I go to all the work of dropping the trans to replace the flywheel and clutch. I have a low mile D/M flywheel sitting on my work bench waiting to that day. H __________________ 90'ZR-1 #1461 Red/Black Ported Intake, Degreed Cams, OBX Headers & Exhaust, Fidanza FW, Secondary Delete, Custom tune, C6 GS Wheels. Sold 08 C6 Z51 Crystal Red Metallic Sold Vararam Intake, Tune, Sold 05 C6 Z51 Red/Black Sold 90'ZR-1 #1723 Black/Gray Sold but not forgotten 91' Z51 L98 White Vert. My First, you always remember your first. Sold.