Hi friends,

I have to relocate the alternator due to a clearance problem.

What I expect from you experts, is to let me know with this deviation from the original setup, how I can improve this or whether this should be good to go.

Here's the summary, details would follow.




First, I have positioned it like so.


Now supporting the top and bottom alternator brackets.

The top bracket is supported from
1. The bolt behind the PAS pump (no image)
2. Engine block to bracket (front)

This is still not fitted properly (or a similar one would be fitted here)

3. Engine block to bracket (rear)



The bottom bracket is supported from
1. PAS pump bracket at front (via new intermediate bracket)


2. Engine block at rear (via new intermediate bracket)




3. Image showing both connections of the lower bracket



The belt would be tensioned as follows:



Then the tensioned position would be secured by this



​​​​​​​

 

Looks OK. Too bad you don't have a double pulley power steering pump.

 

Thank you. I can proceed with finishing up the rest then

 

Are you running A/C? If not, why not just use the OEM passenger side brackets? Yeah, I noticed the RH drive. What car is this in?

 

I'll also add that as a structural engineer, I'd be very skeptical of cantilevering that aluminum cast bracket out like that. Aluminum has a much lower fatigue limit than steel, and since you are not using all the original bolts, expect it to crack and fail sooner rather than later. If you MUST locate the alternator that far outboard, loose the half-fast brackets and make up some decent ones from steel with the same hard points. Your proposed struts have no leverage and will add nearly no stiffness to combat the fatigue-inducing vibrations that will occur.

 

This is in a Holden Kingswood, and I am planning to use an AC compressor, most likely a Sanden style one, no rotary types are found here in Sri Lanka. The original GM Harrison unit is fubar.

 

This is exactly the kind of feedback I wanted to have.
My first language isn't English, so please bear with me on this.

"Loose the half-fast brackets" (not sure what they are)
If you meant "half-fast brackets", the ones I have I have fabricated, well, they are secured by nuts on both ends.
Would it help if I weld that to the lower bracket instead and secure the other end (engine mounting end) by the nut/bolt?

"Your proposed struts have no leverage" (assuming they are the blue ones in the diagram)
The pivot point of the alternator top bracket is the bolt behind the PAS pump.
I thought to use the two rods to counter the alternator's weight.

If I do the exact top bracket from steel instead of aluminum, would that be sufficient?
In that case, maybe I can then use 2 out of 3 bolt holes (pivot and one other) and those rods OR
Use 3 bolts to the head but a huge steel bracket that reaches that far and down to hold entire alternator's weight.

Which would suit better?

 

What you've encountered is slang, and not being a native English speaker (not even sure that that's enough in this case), it's not surprising you're not familiar with it.

"Half-fast" is just slang for "half-assed," which means a poorly done job or a poor quality or poorly made component. By saying "half-fast" instead of "half-assed," Mr. P. can avoid putting a swear word in print (like I've just done).

 

Oh OK, thanks to you and thanks to Mr. P. for being kind to me

 

Is hood clearance a problem? Is this why you are going outboard instead of up with the alternator? Olds build a few million V8 cars with the alternator above the PS pump on A/C cars. The alternator is a not insignificant mass, so the further you cantilever it away from the engine, the higher the loads on the brackets and mounting points (including the bolt bosses in the heads and block) and the more likely that vibrations during operation can lead to fatigue loading and cracks. That aluminum bracket is designed to carry loads into all of the mounting bolts, using just one of them is not a good idea.

If you are stuck with that outboard mounting location, throw away all the current brackets and sketch out something with triangulation. People have made lightweight, stiff, and strong accessory brackets using tubular struts with rod ends. This has the added advantage of also providing easy belt adjustment through the threads on the rod ends. The primary load carrying point on the alternator is the boss with the larger bolt. This can be on top or on the bottom, it doesn't matter. A tripod that picks up that large boss, distributed widely on the block and head, will be the best design. The smaller fastener on the alternator is the adjustment point and a single strut to that point works fine if the other end is well triangulated. Consider using head bolts with accessory mounting studs as hard points for triangulation. Spend some time browsing the web for examples of aftermarket or fabricated outboard alternator brackets. Here are a few as examples. By the way, not all of the designs you'll find on the web should be considered "best practices".

 

Thank you, I totally understand your point. (had to read a few times again and again)

Yes, the hood clearance is a problem (had to grind the oil filler cap's tab too, to clear the hood) and also the top radiator hose rubs on the alternator belt when adjusted (this is a narrower radiator than that of the Custom Cruiser). Also, the top hose had to go through the alternator belt as well, so that's why the alternator was positioned this way.

I thought to use the stock bracket because then belt alignment is on point. Dealing with belt misalignment is such a headache. I am hobbyist and not a professional fabricator.
But I will look around for a suitable alternative. Don't want this to crack and fail too. That one in the bottom picture looks so neat.