Hitachi alternator mounting

[RootesRooter]

Decided to switch to the Hitachi unit to resolve a charging problem. I'd already done this to my other SV. On that one, a friend with a welder filled the existing holes on the stock mounting bracket and redrilled them right next to the old holes (think of a figure-8). That aligned the new pulley.

I've read here where other owners have simply re-positioned the Hitachi unit on the front of the stock bracket and they thought the alignment turned out fine. I tried that tonight. From what I can see, the alt pulley is about 1/2" forward. It appears there's just enough clearance for the belt.

Does anyone have long-term experience with this slightly off-kilter setup? Any burned out bushings?

BTW, Hitachi's unit has been replaced by remanufactured units of in-house brands at Autozone, O'Reilly's, etc.

 

[Tom H]

I am 99% sure that running with a misaligned alt pulley will have a very poor result. When I did my Hitachi ALt conversion I had to elongate the holes in the bracket. But others have typically not had to do so, but still had pulleys aligned and I do not understand how they achieved that. But you must get them aligned. Otherwise I think the belt will overheat and fly off.

Tom

 

[Ken Ellis]

If you have access to a milling machine, you can skip the welding. Or visit a machine shop for 10 minutes. I did this with an end mill.

http://www.sunbeamalpine.org/forum/attachment.php?attachmentid=8149&stc=1&d=1505045340

 

[Jay Laifman]

I would have to go look. I seem to recall that I made two short thick aluminum pieces with two holes, maybe 2" apart. I just mounted them to the tabs on the alternator and used fender washers to space it out perfectly. Perhaps a bit crude. But it mounted perfectly and 25 years later, no issue.

Let me know if that doesn't make sense.

I seem to recall that one of them might have spread across the front of the front tab and the front of the mount, with one or two washers on one of them, and the rear tap had a slightly larger gap, but also filled with washers. But I could have that switched around in my memory.

 

[RootesRooter]

That about looks like the first bracket I had done, except the original holes were filled in first for strength.

 

[Barry]

I am 99% sure that running with a misaligned alt pulley will have a very poor result. When I did my Hitachi ALt conversion I had to elongate the holes in the bracket. But others have typically not had to do so, but still had pulleys aligned and I do not understand how they achieved that. But you must get them aligned. Otherwise I think the belt will overheat and fly off.

Tom

Right on! A v-belt will tolerate a little misalignment, but a serpentine belt is much less forgiving.

 

[mightyohm]

What are folks using for the adjusting strap / top mounting bracket for the Hitachi alternator? It seems like the upper mounting hole is clocked at 12 o'clock on the Hitachi and about 10 o'clock on the stock Lucas, relative to the bottom mounting holes. Doesn't that mean that the alternator top mounting hole will want to sit past the end of the stock mounting strap?

 

[Jay Laifman]

I just got a nice chrome aftermarket one at my local auto parts store. Probably Pep Boys, maybe Napa. I've found that at least our local Napa has guys who actually know about cars.

 

[Hillman]

What are folks using for the adjusting strap / top mounting bracket for the Hitachi alternator?

I made one out of a scrap piece of steel. Drill the appropriate size holes at each end of the 'adjustment range' and using a staight edge and a cutting wheel on a dremel, cut the slot.

 

[Tom H]

I added an extension. Bolted a short adjuster I found at a junk yard and simply bolted it to the end of the original adjuster, at a slight angle to make a hockey-stick-shaped adjuster.

It's held up for 21,000 miles so far.

But be sure to strain relieve the heavy cable to the B+ post, with a clamp or tie wrap, so the engine vibration does not cause the wire to break right near the post.

Tom

 

[mightyohm]

Jay - I'll check the local auto parts stores, thanks for the suggestion. I did see someone mention cutting down the bracket for a V8, that seems like it might work well.

Hillman - That's a great idea. I guess I could even have a part water jet cut if I wanted to get fancy about it.

Tom - thanks for clarifying - just like Tom W's article doesn't mention having to modify the bracket, none of the more recent Hitachi posts mention having to fab an adjustment strap! I think I have the full story, now. I will be careful to strain relief the wiring - I'm making all new cabling for the alternator so I'll be able to route it how I want.

Thanks for all of the help!

 

[phyrman]

If anyone can come up with a sample of one which works for all, I have access to a water jet cutter and I get stuff done CHEAP!!!!! Such as the starter washers I had made
DanR..??????

Bruce