Go Back   986 Forum - for Porsche Boxster & Cayman Owners > Porsche Boxster & Cayman Forums > Boxster General Discussions

Reply
 
LinkBack Thread Tools Display Modes
Old 07-29-2015, 11:33 AM   #1
Registered User
 
Join Date: Apr 2013
Posts: 44
New rattle - timing chain

Started the car yesterday after it sat in the rain for four days. Sounded Ok for a mile, then I heard a light rattle start up. When the car is static and out of gear and I rev it up, the rattle rises with the revs, so it sounds like engine-related rather than clutch or gearbox. Funny thing is that it started suddenly. I have taken the car up to red-line a couple of times and it is running well. I can hear it clearly when listening under the back of the car when idling. The car has 48k miles on it, and always had frequent oil changes with Mobil1. Timing chain perhaps? Any other thoughts?

56 Spider is offline   Reply With Quote
Old 07-29-2015, 11:36 AM   #2
Registered User
 
epapp's Avatar
 
Join Date: Aug 2013
Location: Bay Area
Posts: 700
Garage
Take the engine access cover off and remove the belt. Start the engine and see if the noise is gone. If it is, the noise is probably one of your idler pulleys. Other possibilities include water pump, AC/alternator pulley bearings.
epapp is offline   Reply With Quote
Old 07-31-2015, 07:53 AM   #3
Registered User
 
Join Date: Apr 2013
Posts: 44
Thanks epapp. Yes, examining the belt pulleys would be my first diagnostic check. Having run the car a few more times the rattle does not happen immediately on startup, so hopefully not an IMS or timing belt problem. From reading other messages these seem to be more evident on startup.
56 Spider is offline   Reply With Quote
Old 07-31-2015, 07:54 AM   #4
Registered User
 
Join Date: Apr 2013
Posts: 44
I meant timing chain of course, not belt!!
56 Spider is offline   Reply With Quote
Old 08-18-2015, 09:04 AM   #5
Registered User
 
Join Date: Apr 2013
Posts: 44
Well the noise went away and all was fine for two weeks. Today I heard a screetching noise, the temp light came on almost immediately and then the engine shut down. I topped up the water reservoir after letting everything cool down, and the engine runs but the screetching is still there. There is also water dripping under the engine, so it sounds like the water pump has gone.
Just goes to show that if you hear an unusual noise, there is usually something about to fail!
Tow truck is on the way!
56 Spider is offline   Reply With Quote
Old 08-18-2015, 09:34 AM   #6
Registered User
 
epapp's Avatar
 
Join Date: Aug 2013
Location: Bay Area
Posts: 700
Garage
If you had taken the drive belt off, you would have easily found the sound to be the water pump before it failed!

:screeeeeeeech:
epapp is offline   Reply With Quote
Old 08-20-2015, 11:12 AM   #7
Registered User
 
Join Date: Apr 2013
Posts: 44
Yes, you are probably right, but we have been busy with house renovations the last two weeks, and some travel. And the noise had gone away!! I just hadn't had time.
My repair shop has confirmed the bad pump and a shredded belt, They will flush everything out before fitting the new pump, so hopefully everything will be OK after that. The motor had just reached 50,000 miles, so about time I guess.
56 Spider is offline   Reply With Quote
Old 08-20-2015, 11:30 AM   #8
Registered User
 
epapp's Avatar
 
Join Date: Aug 2013
Location: Bay Area
Posts: 700
Garage
You generally fail first before you succeed! Now you know
epapp is offline   Reply With Quote
Old 08-20-2015, 12:38 PM   #9
Registered User
 
CoBeerToad's Avatar
 
Join Date: Jun 2012
Location: Peoria IL
Posts: 529
Garage
This reminds me of a couple seasons ago, I was driving my car (60 mile commute back then) and when I pulled on the exit ramp I heard a load thump right behind me. This was followed by a few more loud thumps and then nothing. As I made the turn onto the main road, I noticed I had no more power steering so I knew what just happened. All I could think of is what component just died to make the belt snap. Managed to get it home without overheating it and the next day I peered into the service compartment. I had lost the idler pulley and not only did I find all the pieces of the pulley, but the belt was in perfect shape. Not a mark on it. Bought a new pulley and installed the old belt as that was the last drive before winter set in anyway and I was back in business.
CoBeerToad is offline   Reply With Quote
Old 08-20-2015, 12:53 PM   #10
Registered User
 
Join Date: Jan 2007
Location: BC
Posts: 1,278
Was the pump impeller intact when the pump was pulled off? If not, and you can't find all of the pieces, then some small ones could have travelled into the engine and got lodged there, particularly in the small passages in the heads. This could lead to local hot spots and possible head cracking. Backflushing MAY help to find the missing pieces, but is not easy.
__________________
2001 Boxster, 5 spd, Seal Grey
clickman is offline   Reply With Quote
Old 08-20-2015, 01:43 PM   #11
Engine Surgeon
 
Join Date: Aug 2008
Location: Cleveland GA USA
Posts: 2,424
If you remove the pump, and impeller blades are missing, you have a bigger problem. Those must be fetched, else you'll crack a head.

__________________
Jake Raby/www.flat6innovations.com
IMS Solution/ Faultless Tool Inventor
US Patent 8,992,089 &
US Patent 9,416,697
Developer of The IMS Retrofit Procedure- M96/ M97 Specialist
Jake Raby is offline   Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -8. The time now is 07:36 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page