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Tech Talk => Engine Mechanical / Electrical => Topic started by: selbycnlb on July 11, 2017, 10:09:23 PM

Title: Screeching only when the secondaries kick in.
Post by: selbycnlb on July 11, 2017, 10:09:23 PM

Newer build on a BBC have not been able to open it up because when I hammer down it makes terrible sound. Any ideas?


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Title: Re: Screeching only when the secondaries kick in.
Post by: connorstexas on July 11, 2017, 10:42:22 PM

my old carrera did that, it ended up being the alt belt.


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Title: Re: Screeching only when the secondaries kick in.
Post by: el mojado on July 12, 2017, 12:12:36 PM

I run a vac secondary holley 750. When WOT I hear a whistling sound in mine. Not sure if that's the type of noise u hear or is it something more extreme.

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Title: Re: Screeching only when the secondaries kick in.
Post by: selbycnlb on July 12, 2017, 07:33:33 PM

I run a cam driven alternator no belts. This sound has a grinding screech more than a whistle. It makes me throttle down but seems to run fine on primaries. I switched from a 950 dp to 850 dp and it did it in both cases.


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Title: Re: Screeching only when the secondaries kick in.
Post by: Flusher on July 12, 2017, 08:28:58 PM

Quote from: selbycnlb on July 12, 2017, 07:33:33 PM

I run a cam driven alternator no belts.

That sounds bitchen!  Any pictures?

Title: Re: Screeching only when the secondaries kick in.
Post by: bobjthomson on July 12, 2017, 08:32:20 PM

Pull ur alternator an test it , sounds like a bad bearing , I had the same problem on my crank driven one


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Title: Re: Screeching only when the secondaries kick in.
Post by: selbycnlb on July 14, 2017, 09:58:45 PM

My bad guys crank driven. I am switching water pumps at the time and have a cam driven water pump. Did the alternator sound fine at low rpms then screech when spinning 4500+?


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Title: Re: Screeching only when the secondaries kick in.
Post by: selbycnlb on July 14, 2017, 10:02:48 PM

It is a brand new alternator. The screech was present on old one also present on new one so I would think it is something else.


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Title: Re: Screeching only when the secondaries kick in.
Post by: bobjthomson on July 15, 2017, 12:39:16 PM

What water pump are u using ? Is it old ? My pump bearings were bad an got the kit from glenwood


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Title: Re: Screeching only when the secondaries kick in.
Post by: selbycnlb on July 15, 2017, 09:26:35 PM

I currently have the neovane 105. Just fished out about five impeller fins in the distributor section of the pump this morning.I also have a magnaflow 1" in the garage that is awaiting a impeller. Gonna test tomorrow to see if anything changes


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Title: Re: Screeching only when the secondaries kick in.
Post by: selbycnlb on July 21, 2017, 08:53:26 AM

Temps are better but the screeching is still present when the secondaries kick in.


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Title: Re: Screeching only when the secondaries kick in.
Post by: bobjthomson on July 23, 2017, 11:10:58 AM

Can u take vid when running ?


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