Author Topic: Grounding the alternator  (Read 5174 times)

Offline Eagle Andy

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Grounding the alternator
« on: October 08, 2010, 08:54:48 PM »
Today I was looking at the ground on my alternator and noticed it was grounded to a bracket that is part of the frame work around the engine compartment. Is is best to ground it to the motor . ??? or does it matter. Thanks for any advice Andy
1968 Model 05 Eagle # 7481 Miles City MT

Offline luvrbus

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Re: Grounding the alternator
« Reply #1 on: October 08, 2010, 09:38:43 PM »
To the frame Andy were the Eagles were grounded, that is not the 05 original alternator looks to me like one from a truck Terry did a good mounting it

good luck
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Offline bevans6

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Re: Grounding the alternator
« Reply #2 on: October 09, 2010, 05:05:35 AM »
Always to the frame, so that the circuit back to the batteries is as direct as possible.  It's often good to establish a solid ground between the engine and the frame as well, so that connection is unquestionable.

Brian
1980 MCI MC-5C, 8V-71T from a M-110 self propelled howitzer
Allison MT-647
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Offline Eagle Andy

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Re: Grounding the alternator
« Reply #3 on: October 09, 2010, 06:49:47 AM »
Thanks  I wonderd about that ground  ;D You are right Clifford , that is a 135  amp truck alt and if you look close at that hot wire it looks a little small what do you think ?  And does it matter how long the ground wire is could I run it back down to the frame rail or back over to the ground connection that the battrey grounds to ?
« Last Edit: October 09, 2010, 07:02:16 AM by Eagle Andy »
1968 Model 05 Eagle # 7481 Miles City MT

Offline Eagle Andy

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Re: Grounding the alternator
« Reply #4 on: October 09, 2010, 04:16:25 PM »
Ok I got one of the answers I was looking for but I another ? . Can I run my alternator ground over to the place where my start battries are grounded. or can I just ground it to the motor on the driver side .
1968 Model 05 Eagle # 7481 Miles City MT

Offline FloridaCliff

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Re: Grounding the alternator
« Reply #5 on: October 09, 2010, 04:36:27 PM »
Andy,

It will work going to the engine, but running to the common battery ground is better.

The use of the frame as ground works, but is done to save on wiring by the manufacturer.

Running separate grounds to a common ground bus is "best practice", but seldom done.

Best of luck,

Cliff
1975 GMC  P8M4905A-1160    North Central Florida

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Offline Eagle Andy

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Re: Grounding the alternator
« Reply #6 on: October 09, 2010, 05:48:19 PM »
Thanks Cliff , I had heard that before but wasn't sure . that's what Iam going to do . with that lite alt 135 amps I need all the help I can get. Thanks to all  Andy
1968 Model 05 Eagle # 7481 Miles City MT

Offline bevans6

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Re: Grounding the alternator
« Reply #7 on: October 09, 2010, 05:55:40 PM »
if you are going to run the ground a long distance, make sure you size it appropriately.  it carries all the current the alternator generates.

Brian
1980 MCI MC-5C, 8V-71T from a M-110 self propelled howitzer
Allison MT-647
Tatamagouche, Nova Scotia

Offline Eagle Andy

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Re: Grounding the alternator
« Reply #8 on: October 09, 2010, 06:20:40 PM »
Will do thanks Brian
1968 Model 05 Eagle # 7481 Miles City MT