Tom M'Guinn

Just discovered the lower alternator bolt hole needs drilling too, and needs a little strengthening rib ground off. No biggie, but I just unwrapped the alternator from it's saran wrap cocoon after doing all the other grinding.

Did you use the grinder to cut the big hole in the bracket as well? I went at it with my Dremel, but it was way thicker than I expected! Need something bigger it seem....

mahoney944

Yes I did. I used a thin disc in my grinder to cut it out and a thicker one to round over the edges.

Tom M'Guinn

I'm growing surprise this alternator is not a closer fit than it is. Here's my running list of things I've had to do so far:

1. Grind upper alternator mounting ear so pulleys line up, as described above
2. Grind material away from lower mounting ear so lower mount clears bracket
3. Grind away a little of the bracket to help the lower mounting ear clear
4. Remove section of the bracket as shown above so alternator can pivot into position without hitting
5. Drill out holes on alternator mounting holes to accept factory M10 bolts
6. Order longer M10x140mm bolt for upper (pivot mount) and add lock nut to back (in lieu of trying to tap the mounting hole alignment inserts in the alternator)

The alternator now fits without anything hitting (whew), but the lower bolt hole is about 1-2mm off, preventing the lower M10 bolt from going through when the upper pivot bolt is installed. I already drilled that hole in the alternator to 13/32", to essentially match the 10mm factory holes, but what did others do? Drill it bigger? Use an M8 bolt instead? I just assumed the mounting ear locations were identical to the factory alternator, but at least mine is clearly off a few mm's.

mahoney944

I just tapped the rear sleeve of the alternator tab to the factory bolts thread, that way no locking nut was needed and factory bolt was reused. I don't recall drilling the front tab, But I probably did too. Once your done its a great mod. I had one Nissan alt act up on me awhile ago so I bought another one and swapped its guts into my pre fitted housing. Very simple and cheap

Tom M'Guinn

It may be that the cases vary on these things from mfg to mfg. I drilled the lower mounting ear hole to 7/16" and that allows the bolt to slip through. No way it would have aligned if just tapped.

Next issue is that the landing surfaces of the upper and lower mounts aren't in the same plane when you grind the upper to match the factory pulley. In other words, when you take about 6mm off the pivot mount ear so that the pulleys line up (as in post 32), the non-pivoting lower mounting ear stands proud about 1-2mm, so that will need to be resurfaced as well so that everything aligns. Otherwise you can take as much as you want off the pivot ear and it will never sit flush since the lower/non-pivot ear is about 1-2mm too thick.

Thanks for your help, and I'm not complaining -- just documenting for those who do it going forward. I personally didn't appreciate how much customizing was needed to the bracket and alternator case to make it work. Maybe others had alternator cases that fit better to start -- I've been using the eBay version with the 6-rib pulley -- or maybe I'm fussier than others...

mahoney944

The casings do vary. And sorry if you found it troublesome. I didn't create this mod, but it is worth it when it's done. Especially when upgrading the car later

Tom M'Guinn

No, no apologies needed at all -- seriously appreciate your help! I'm looking forward to having the extra room for sure! I do think my case presented more challenges than some, based on what I've read, unless I really am fussier than others. I'm just about done, and could run it the way it is now, but there is still a very slight gap between the front pivot mount and the bracket when all bolted up -- like maybe 10-20 thousandths, so I should be able to even out the ear heights to close that gap tomorrow. It doesn't help that it's over 100 degrees today, and I'm doing the grinding outside my garage on the sunny side, in what amounts to an Easy-Bake oven... Maybe that's coming across in the tone of my posts.

mahoney944

From what I've seen there are many aftermarket alternators being sold that are replacements for the Nissan alt that we use. The castings can be quite different from different venders. So people reported that their alt bracket didn't need modded at all while others like me had to cut a piece out for clearance. I had to grind a decent bit but my dewalt cutoff wheel zipped through it with ease. It's definitely more work on the initial install but it pays off and the benefits are great..... more room, higher volt output, more air flow, spins slower at highway speeds, cheap parts if replacements are needed. I bought an extra one for how cheap they are for parts lol

Tom M'Guinn

Ok, fairly sure I'm done with the bracket. Thought I'd post a picture in case helpful to anyone going forward. It shows the three places where I needed to remove material for the eBay alternator to clear. The bracket is *very* thick, so I ended up starting the cuts with a cut-off wheel along with a Dremel, and drilled lots of tiny holes in the cut line to speed up the process. I'll post the alternator mods as well tomorrow.

Tom M'Guinn

Ok, got the car back together with new alternator (and turbo and bunch of while your in there stuff)... Alternator is aligned nicely and working, but I'm seeing 14.05 volts at idle on my multimeter, with all accessories off. I wired as suggested here. What voltage are others seeing?

mahoney944

14.3v or so on start up then normally a little lower once the cars completely warm. Ive heard of people seeing a tad higher but I wasn't too concerned. The car only needs 12v for normal operation and my stock alt could barely charge to 12.5v to 13v. I also suspect my battery to starter cables are not 100%

Tom M'Guinn

That's pretty much my experience as well -- started up with the needle just over 14. By the time I got the multimeter on the battery it was 14.05. Then drove around a couple miles and it was right where is always was before on the gauge at about 13.8. The extra room is fantastic -- put a new turbo in at the same time and it's so much easier to get the j-boot on without that big bulky alternator right in the way!

User 52121

Sounds about right. I think you're good!

rluciano

Also don't trust the factory gauge. My actual voltages are similar to Tom's, but my factory gauge is more than 1v lower than that. Of course I don't trust any of my factory gauges. I use a Bosch DDU7 for my gauges.

Tom M'Guinn

Here is a summary of the things I did to make the alternator fit, in case helpful. Not much new here, just putting all the details in one place from my project.

Alternator:

1998 Nissan Quest sold with 6-rib pulley (in lieu of original pulley that comes with alternator – i.e., don’t expect an alternator from your local parts store to have the right pulley). You need to request this pulley when ordering.

http://www.ebay.com/itm/100-NEW-ALTE...d1232f&vxp=mtr

Electrical Jumper for alternator:

Part # C1900. I terminated the wires with a standard WeatherPac and eye-ring connectors as shown. (You could also use spade connectors in a pinch.)

http://store.alternatorparts.com/partnoc1900.aspx



Post Insulator:

I found these post insulators at Summit – Ron Francis CC14 post boots. They are an ok fit – way better than not having-- but still on the look-out for something that seals around the alternator post a little better.
http://www.summitracing.com/parts/rfw-cc14

Bolts and nuts: I had to use a 140mm M10 bolt on the pivot mount of the alternator, with a mechanical locknut on the back end. After grinding the tabs, there will be a gap between the pivot ears when you install the alternator and slide the 140mm bolt in place. Be sure to install washers/spacers so that the alternator sits in the bracket snugly. I used a thick M10 washer and ground it a bit thinner as needed so that the alternator was factory-tight in the bracket. Otherwise, the alternator might wander forward/backward and prematurely wear the belt. I used 65mm M10 bolt on bottom, also with lock nut. McMaster sell any hardware you might need.


In the picture of the alternator below, the blue arrows show the electrical connections. I used WeatherPac connectors to mate the blue wire in the factory/iceshark harness to the blue wire on the alternator. I added a standard eye-ring connector on the red wire, and adhesive lined heat shrink.

The arrows marked A show where I ground down both surfaces so the pulleys all line up. I had to remove just under 6mm from the pivot mount side and about 2mm from the fixed mount side.

The arrows marked B show where I had to grind away material to clear the factory mounting bracket. The red arrow marked C shows where I had to grind about 8mm off the forward face of that mounting tab, to prevent the bolt from hitting the belt that passes right in front of that tab.

The green arrows point to where I drilled the mounting holes. I used a 13/32” on the pivot side (i.e., the closest I had to 10mm) but had to use 7/16” on the fixed mount side in order to get the bolt to slide through.

Picture of bracket shows where I ground/cut for the alternator to clear. Also pictured is the Ron Francis post boot.