Notices
928 Forum 1978-1995
Sponsored by:
Sponsored by: 928 Specialists

Strange engine sound (video)

Thread Tools
 
Search this Thread
 
Old 04-09-2018, 06:02 PM
  #1  
concor
Racer
Thread Starter
 
concor's Avatar
 
Join Date: Nov 2008
Location: The Netherlands, Zwolle
Posts: 286
Likes: 0
Received 3 Likes on 3 Posts
Default Strange engine sound (video)

So, last major job was the timing belt, the accessory belts and the rollers. Done by my mechanic who knows his stuff. However, changing oil this weekend with my head under the bonnet, I noticed that the engine is now making a faint but odd metal scraping noise. I made a video of it below to record the sound.

Does someone perhaps know what could be making that noise? Thanks in advance.


Last edited by concor; 04-10-2018 at 05:54 AM.
Old 04-09-2018, 08:47 PM
  #2  
Mrmerlin
Team Owner
 
Mrmerlin's Avatar
 
Join Date: May 2004
Location: Philly PA
Posts: 28,487
Received 2,587 Likes on 1,456 Posts
Default

shut if off and remove the belt covers take pictures as this done .
Disconnect the battery so the engine cant run untll this issue is fixed
Old 04-09-2018, 10:55 PM
  #3  
Wisconsin Joe
Nordschleife Master
 
Wisconsin Joe's Avatar
 
Join Date: Jan 2013
Location: Kaukauna Wisconsin
Posts: 5,926
Received 303 Likes on 232 Posts
Default

Something is not right.

I can't tell you if it's something outside the TB cover (accessories) or something under it (TB/WP/tensioner/oil pump).

Since it's an S2 (84 - 86 Euro), it's likely an interference motor. If the TB goes, so goes the motor.

I would tow it back to the shop and have them fix it.

Correctly this time. The job was either not finished or not done correctly.
Something was left undone or loose, or screwed up.
Old 04-10-2018, 10:47 AM
  #4  
bureau13
Rennlist Member
 
bureau13's Avatar
 
Join Date: May 2014
Location: South Florida
Posts: 3,488
Received 57 Likes on 43 Posts
Default

You might be able to localize it better with a mechanics stethoscope. That would tell you pretty quickly if it was accessory-related.
Old 04-10-2018, 11:39 AM
  #5  
Ducman82
 
Ducman82's Avatar
 
Join Date: Nov 2009
Location: Marysville WA
Posts: 6,983
Received 18 Likes on 11 Posts
Default

pull the covers. something in the timing system is rubbing somewhere.
Old 04-10-2018, 12:02 PM
  #6  
Kevin in Atlanta
Rennlist Member
 
Kevin in Atlanta's Avatar
 
Join Date: May 2002
Location: Roswell, GA
Posts: 8,218
Received 837 Likes on 506 Posts
Default

Sounds like it is accessory related.

If you want to rule out accessories use white out to mark each belt and see if their appearance in view coincides with the sound.
Old 04-10-2018, 12:42 PM
  #7  
davek9
Rennlist Member
 
davek9's Avatar
 
Join Date: Jul 2006
Location: Bloomfield, MI
Posts: 5,188
Received 384 Likes on 207 Posts
Default

That spinning fan made you jump hey, made me giggle

How many T-Belt jobs on a 928 has he done? I ask because I know of a "experienced and good mechanic" who called me saying he had to remove a Cam Gear to get the T belt on. When he stated he had to pass the belt "through" the tensioner arm, I knew exactly what he did wrong.
He was glad he didn't start the engine and called me to be sure, I got a big thank you and 12 pack for Fosters Dirty Bastard of my assist

Don't run it (like Stan said) until he looks it over his work else could be big issues if you continue to spin the wheel of chance.

Dave K
Old 04-10-2018, 01:15 PM
  #8  
Tony
Addict
Lifetime Rennlist
Member
 
Tony's Avatar
 
Join Date: May 2001
Location: Las Vegas
Posts: 14,676
Received 584 Likes on 305 Posts
Default

pull the plastic air intake tubes and look down the breather hole of the timing belt cover...see if the belt is tracking correctly and if there are any unusual marks as it tracks. could be as simple as part of the front Timing belt cover rubbing on the balancer...or a misaligned idler... what ever the case, over time it will cause a bigger issue than you hear now. Our cars, like our bodies, often give us clues in advance that something isn't quite right... This isnt right.
Old 04-14-2018, 12:16 PM
  #9  
concor
Racer
Thread Starter
 
concor's Avatar
 
Join Date: Nov 2008
Location: The Netherlands, Zwolle
Posts: 286
Likes: 0
Received 3 Likes on 3 Posts
Default

Okay I am an idiot! The problem was not enough oil! After changing the oil and filling it up nicely between the two lines on the dip stick I thought I was done. I forgot to start the engine to fill up the oil filter and the rest of the engine and hoses. So it just had not enough oil!

I am so happy though that it was just this. I was tinkering for days about how to remove those timing belt covers. And who should be responsible, my mechanic or me. I do want to thank all the people here giving their thoughts and advice. I highly appreciate it. Now, and during the past 10 years I'm driving this car. And I can now go the meeting tomorrow of 'Opkikkerdag' which is something for families with sick children. Lastly here's a video of the 'new' engine sound:

Old 04-14-2018, 09:51 PM
  #10  
Mrmerlin
Team Owner
 
Mrmerlin's Avatar
 
Join Date: May 2004
Location: Philly PA
Posts: 28,487
Received 2,587 Likes on 1,456 Posts
Default

adding oil is not the going to make that sound go away.
if you filled the oil up to between the lines then you had more than enough oil in the engine to have it operate at idle,
it will fill the filter and cooler in about 20 seconds.
disconnect the battery .dont keep testing the belt .
and remove the belt covers post pictures of the belt run as the covers come off.
I am hearing noises that indicate something may not be right.
It should sound like this




Quick Reply: Strange engine sound (video)



All times are GMT -3. The time now is 05:14 AM.