alternator ground connection

[Lucky 76 5]

the alternator i have is a single wire and does not have a ground connection. it is mounted on 2 bolts that screw in to the engine block. is it alright that i grounded the engine block to chasis instead?

[CrazyKenKid 64]

the alternator i have is a single wire and does not have a ground connection. it is mounted on 2 bolts that screw in to the engine block. is it alright that i grounded the engine block to chasis instead?

ya my alt also doesn't have a ground wire but it also mount with 2 screws and those 2 screws on mine are the gronding spots! so to complete the big 3 jsut run a wire from one of the 2 bolts to the chassis that way your alt and engine block will be grounded!! you might want to use 2 wires of 0/1 though!!

wiat what are you asking? is it okay to ground your engine block to the chassis instaed...instead of what? Grounding your alt and engine to the chassis?

but by grounding one your ground the other so...you may be okay!!

sorry me vs reading and reading always wins!!

[jcarter1885 995]

I did the same thing since my alternator is didnt have an actual ground wire coming from it. I just upgraded the wire leaving the engine block to the cars chasis that was their from the factory to 1/0 awg wire.

[Spencerk 4]

I would put a wire right from the alt to the chassis some alts have aluminum casings with steel hardened bolts holding them on. this combo can lead to poor grounding. Just pull one mounting bolt and clean the area and place your ground their. just my .02

[jcarter1885 995]

If i upgraded the wire coming from my engine block to car's chasis with 1/0 awg wire, then I should also add a 1/0 awg wire leaving my alternators casing to the car's chassis also even though their is no ground wire on my alternator period?

[Spencerk 4]

well... yeah because when you have two types of metals you can get galvanic corrosion between the two and that will cause problems. if you do put a wire right to it put some die electric grease on their to stop the oxidation ( the root cause of the galvanic corrosion

the casing of the alt is its ground

Edited July 8, 2009 by 144dbFiBl15

[jcarter1885 995]

well in my case i dont have an aluminum casing for my alternator, the bolts are the same color and made from the same metal as the alternator

[Tirefryr 1,742]

well in my case i dont have an aluminum casing for my alternator, the bolts are the same color and made from the same metal as the alternator

All alternator frames are aluminum and they all ground through the frame when it's bolted to the block. The bolts may appear to be of the same material, but they are not. They are steel.

[jcarter1885 995]

ok thanks for the correction, learn something new everyday. well i upgraded the factory wire leaving the engine block to cars chassis(sanded paint and cleaned with degreaser) from 4 gauge to 1/0 awg wire. My whining went away that I had ever since I got the car and put a stereo in it and my voltage is great and steady even while idling but before both were problems since saturn doesnt ground to an unpainted frame(both battery in trunk and engine block underhood were grounded to painted frames). As stated early by the person who started the topic he wanted to know was upgrading the ground wire leaving the engine block to the car's chassis ok if you dont have a ground wire leaving your alternator (I was wanting to know the same thing)? Somebody stated that we should add a ground to alternator to car's chassis also, is that necessary also?

[Spencerk 4]

I suppose you don't have to if ya don't want, but bc the alt is the main source of power in your car and the ground comes from its casing its deff not going to hurt. To give your alt the path of least resistance that would be the way to do it. Even if ya don't put a wire on it proly would not be a bad idea to pop out the bolts and just make sure the you have a good clean connection with the block.

[Tirefryr 1,742]

Isn't always the path of least resistance, but general consensus. It definitely cannot hurt.

You can also, just leave all stock wires in place, or if you change them out, always upgrade the size.