Odd Noise Coming from Engine
Thread Starter
Instructor
Joined: Oct 2013
Posts: 137
Likes: 1
From: Fairborn Ohio
Odd Noise Coming from Engine
My son's '93 C4 has recently presented a noise that I originally thought to be loose lifters. I opened the valve covers and didn't see anything strange - nothing cracked, no bent push rods, nothing that would cause a sound from the lifters. Then I thought it to be a bearing from the AC condenser or alternator. I took off the serpentine belt and the sound did not go away. Could this be the water pump? or maybe a rod bearing? or a main bearing? or exhaust leak?
Thread Starter
Instructor
Joined: Oct 2013
Posts: 137
Likes: 1
From: Fairborn Ohio
Self Healing Car?
[QUOTE=JayEmEss;1589202023]My son's '93 C4 has recently presented a noise that I originally thought to be loose lifters. I opened the valve covers and didn't see anything strange - nothing cracked, no bent push rods, nothing that would cause a sound from the lifters. Then I thought it to be a bearing from the AC condenser or alternator. I took off the serpentine belt and the sound did not go away. Could this be the water pump? or maybe a rod bearing? or a main bearing? or exhaust leak?
My son and I diagnosed all day today and sought advice to include scheduling an appointment at a local transmission repair shop. Why the transmission repair shop? We used a stethoscope to isolate the sound we were hearing - something on the order of a bearing with a high frequency pitch. The sound was coming from the flywheel. We looked in the FSM and determined the flywheel cover was loose or somehow coming in contact with the flywheel. Well, we had the car on jackstands and opted to take the car down from the jackstands. My son took the car down and I left the garage temporarily. When I returned, he had backed his 93 Vette out of the garage and was looking at me with a large grin. I listened and discovered his car was running with no Squealing sound! We don't know what happened but obviously whatever was contacting the flywheel no longer contacted the flywheel. To say we were glad is an understatement!
My son and I diagnosed all day today and sought advice to include scheduling an appointment at a local transmission repair shop. Why the transmission repair shop? We used a stethoscope to isolate the sound we were hearing - something on the order of a bearing with a high frequency pitch. The sound was coming from the flywheel. We looked in the FSM and determined the flywheel cover was loose or somehow coming in contact with the flywheel. Well, we had the car on jackstands and opted to take the car down from the jackstands. My son took the car down and I left the garage temporarily. When I returned, he had backed his 93 Vette out of the garage and was looking at me with a large grin. I listened and discovered his car was running with no Squealing sound! We don't know what happened but obviously whatever was contacting the flywheel no longer contacted the flywheel. To say we were glad is an understatement!
Burning Brakes
Joined: Apr 2012
Posts: 888
Likes: 4
From: Ridgecrest Ca
[QUOTE=JayEmEss;1589206575]
You gotta love it when the fix cost only a little time.
We looked in the FSM and determined the flywheel cover was loose or somehow coming in contact with the flywheel. Well, we had the car on jackstands and opted to take the car down from the jackstands. My son took the car down and I left the garage temporarily. When I returned, he had backed his 93 Vette out of the garage and was looking at me with a large grin. I listened and discovered his car was running with no Squealing sound! We don't know what happened but obviously whatever was contacting the flywheel no longer contacted the flywheel. To say we were glad is an understatement!
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
[QUOTE=JayEmEss;1589206575]
My prof in automotive school's explanation for those situations was:
"Eh....AMFM." (AutoMotive Feking Magic)
The sound was coming from the flywheel. Well, we had the car on jackstands and My son took the car down and I left the garage temporarily. When I returned, I listened and discovered his car was running with no Squealing sound! We don't know what happened but obviously whatever was contacting the flywheel no longer contacted the flywheel.
"Eh....AMFM." (AutoMotive Feking Magic)
