Loud grinding noise up front

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JamusMcFamus
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Location: North Augusta, SC

Loud grinding noise up front

Post by JamusMcFamus »

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.
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alotawatts
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Post by alotawatts »

Often it's more like a squeal ......but:
Three E12's and one R27
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Pierre
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Assume the obvious

Post by Pierre »

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.
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
JamusMcFamus
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Post by JamusMcFamus »

Great advice. Thank you
GripGreg
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Post by GripGreg »

AND, since the mechanic's analysis didn't fix the problem, he should deduct the cost till it's fixed!!!!! :roll:
I don't care where he's from; if it's not fixed after he said he knew the problem, he owes you! :roll:
Greg
JamusMcFamus
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Post by JamusMcFamus »

I would normally agree with you, but he's working for free. My dad is his boss :)
GripGreg
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Post by GripGreg »

Then, maybe, he owes you a beer?
I understand & good for you! 8)
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wkohler
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Post by wkohler »

It's funny, but I've heard this type of grinding sound with alternators. Unfortunately the water pump and alternator are on the same belt. Might be worth putting the alternator on a bench tester like they have at parts stores.
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Pierre
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Location: Camarillo, CA

Noise

Post by Pierre »

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
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Domingo
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Lift...

Post by Domingo »

The wheels and ck the bearings. Replace them anyway...

:wink:
JamusMcFamus
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Joined: Sun Jul 31, 2011 9:42 pm
Location: North Augusta, SC

Post by JamusMcFamus »

Well, it turned out to be a bad water pump. Incredibly, both, the new and old water pumps had bad bearings. Thanks for everyone's suggestions and tips.
GripGreg
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Post by GripGreg »

Don't we love this website?? :D
JamusMcFamus
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Post by JamusMcFamus »

Definitely. I also love boobies.
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Jeff Dennis
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Post by Jeff Dennis »

Yeah to boobies....
Hanging out in Huntsville
1977 530i 60K
1980 525 Euro
1989 E30 Cab
1992 E30 Cab
1976 R75/6
1974 2002
Alfas
GripGreg
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Post by GripGreg »

Got THAT right!!
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