Loud grinding noise up front
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JamusMcFamus
- Posts: 98
- Joined: Sun Jul 31, 2011 9:42 pm
- Location: North Augusta, SC
Loud grinding noise up front
I've recently completed replacing my cracked head with a known good one. Prior to replacing it, and finding out that it was cracked, I noticed a loud grinding noise at the front of the engine. I took it to the local mechanic and he said it sounded like the fan clutch. Since everything was coming off anyway, and I didn't know the age of the currently installed one, I went ahead and replaced it along with the water pump.
Fast forward a few months and everything is rebuilt, just being finely tuned. The grinding is still there. My current mechanic, a BMW Master Tech who has been with the company 28 years, now says it's the water pump. He used the screwdriver-to-ear method and deduced that the sound is definitely coming from there.
Is it really possible that an old, and brand new, pump could both be causing this grinding noise? It sounds pretty gnarly.
Fast forward a few months and everything is rebuilt, just being finely tuned. The grinding is still there. My current mechanic, a BMW Master Tech who has been with the company 28 years, now says it's the water pump. He used the screwdriver-to-ear method and deduced that the sound is definitely coming from there.
Is it really possible that an old, and brand new, pump could both be causing this grinding noise? It sounds pretty gnarly.
- alotawatts
- Posts: 438
- Joined: Wed Jan 07, 2009 3:52 am
- Location: Seattle WA
Assume the obvious
Chances that the old and new WP are making the same noise is unlikely.
So work by elimination.
You have 3 belts. Take them off one at a time, starting and running the car between each removal. If the noise goes away, you know which component is responsible, or at least you can narrow down.
You can spin the water pump and alternator by hand and feel if there is any play, resistance or roughness.
Start with that and report back your findings.
So work by elimination.
You have 3 belts. Take them off one at a time, starting and running the car between each removal. If the noise goes away, you know which component is responsible, or at least you can narrow down.
You can spin the water pump and alternator by hand and feel if there is any play, resistance or roughness.
Start with that and report back your findings.
Pierre in Camarillo
76 530i (3.3), 69 2002 (M20), 74 tii, 75 2002, 79 323i, 84 733i, 84 323i (S52), 91 318is, 96 318ti (S52), 97 Z3, 01 540i, 02 330i, 02 1150RTP.
OO==00==OO
76 530i (3.3), 69 2002 (M20), 74 tii, 75 2002, 79 323i, 84 733i, 84 323i (S52), 91 318is, 96 318ti (S52), 97 Z3, 01 540i, 02 330i, 02 1150RTP.
OO==00==OO
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JamusMcFamus
- Posts: 98
- Joined: Sun Jul 31, 2011 9:42 pm
- Location: North Augusta, SC
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JamusMcFamus
- Posts: 98
- Joined: Sun Jul 31, 2011 9:42 pm
- Location: North Augusta, SC
Noise
In most cases, a bad bearing can be detected by hand. Just turn the pulley back and forth and you should have a smooth glide with no play. A bad bearing will feel gritty and may even be squeaky. It may also catch and release as you turn it.
Pierre in Camarillo
76 530i (3.3), 69 2002 (M20), 74 tii, 75 2002, 79 323i, 84 733i, 84 323i (S52), 91 318is, 96 318ti (S52), 97 Z3, 01 540i, 02 330i, 02 1150RTP.
OO==00==OO
76 530i (3.3), 69 2002 (M20), 74 tii, 75 2002, 79 323i, 84 733i, 84 323i (S52), 91 318is, 96 318ti (S52), 97 Z3, 01 540i, 02 330i, 02 1150RTP.
OO==00==OO
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JamusMcFamus
- Posts: 98
- Joined: Sun Jul 31, 2011 9:42 pm
- Location: North Augusta, SC
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JamusMcFamus
- Posts: 98
- Joined: Sun Jul 31, 2011 9:42 pm
- Location: North Augusta, SC
- Jeff Dennis
- Posts: 478
- Joined: Wed Jan 07, 2009 11:29 pm
- Location: Huntsville, Alabama


