2nd alt bracket, can it mount to body?? Or does engine move to much? Belt align?

[boostNbeer]

Im adding a second alternator to my car, planning on running it off the a/c belt. What Im stuck on is the rbacket to hold the alt in its place.

I took my 2nd battery and air box out and Ive got tons of room to work with, BUT there are no threaded holes on my block or big bolts that I can make a bracket for the alt off of the engine.

The only solution I could find is that there are tons of mounting bolts and spots on the BODY of the car, so my question is can you have the bracket to hold the alt coming off the car only?? Or will the engine move to much and knock the belt alignment off?

I didnt know if the alt had to be bolted to the engine and independent from the body....

Heres what Im workin with, and my idea, Ive got 5" wide 1/4" thick plate to make this bracket out of

I wanna hold it like this

With a bracket that looks kind like this, welding on the standing pieces also out of 1/4" plate, and on the right side mounting point I will make it slotted so I have some belt adjustment....

Im also unsure of exactly how to get the pulley aligned nicely, you can "eye' it, but Im sure the alignment and angle are pretty **** important. Any tips??

Appreciate any constructive criticism

Click to read more...

 

[stangman67 10+ year member]

The engine will move, you need to mount it to the engine, not to the wheelwell

 

[boostNbeer]

I know it "moves" but enough to knock alignment out or make a difference?

This is in a nissan pathfinder if it matters

 

[stangman67 10+ year member]

Yes any engine will move enough to throw off the tension/alignment. The engine will move horizontally as it is revved up. You need the tension in the belt to be perfect and consistent or your belt is going to slip/snap

 

[gtbike900 10+ year member]

you definitely a noob your motor depending on the condition of your motor mount moves 2 to 3 inches

 

[boostNbeer]

lol @ an engine moving 3", dont think so BOY

 

[Street DreamsCC 10+ year member]

Yes it must be mounted to the motor unless you want to keep replacing the belt and burn out the alternator very quickly. You can damage the bearings doing it the way you want.

Either just upgrade your sotck one with a bigger one or have custom brackets made up even if they come off of places like power steering pump bracket, factory alternator bracket etc. It doesnt have to directly bolt up to the motor itself but has to be attached to it in one way or another.

 

[boostNbeer]

Ya thats a problem, the p/s etc is all on the other side, this is all by itself on the drivers side, and on this side of the engine all there is only a few valve cover bolts, and some a/c connections, all of which are like M6 bolts or smaller, wouldnt trust it to hold 50lbs.

Couldnt find a big bolt to save my life on that side

 

[boostNbeer]

Also, any pointers on belt alignment?? and finding that position for the alt to sit BEFORE I final weld or start cutting everything?