Quadratec 150A Alternator

I found this, which is the part number for the 150A unit from the '98 5.9 ZJ limited. Does anybody know if the 136A and the 150A units are the same size/ case? I know I can make the 136A fit with some grinding, but if this has the same overall dimensions I'm going to order it... Says it fits all 93-98 ZJ's, but it could still possibly be a different size since the ZJ mount may allow a bigger case?
http://www.quadratec.com/products/55100_0014.htm

I also found them reman for around $140 which is pretty good IMO, but I want a new one.

the 150A and 136A unit should be the same size case. if you want to double check, go to your local parts store and have them pull both from over the counter. regardless of which route you go, your not going to get the full performance out of it unless you upgrade your mains cables.

keep in mind too, the grand cherokee uses a 7 groove pulley. you can either bias the belt to the rear of the alternator, or swap the 6 grove pulley from your existing alternator.

From what I've been reading, it's pretty difficult to find the 150A and most/ all chain stores only carry the 136A, even for the 5.9. Otherwise, I would definitely just go have someone pull both off the shelf. I plan on order a 4AWG main kit from 5-90 as part of the upgrade. As far as the pulley, I don't think the quadratec one even comes with a new pulley so I'll have to use the old one regardless. I would have to assume the cases are the same size, but I just wanted to see if anyone actually knew for sure...

im pretty confident they are... i walked into autzoone and they had the 150a behind the counter. :dunno: i may have given them the durango part number. i say im pretty confident, because this was a number of years ago.

I may be able to get my hands on a 5.9 for a chance to measure the alternator. Does anyone have a 136A that they can measure the circumference of the case?
Thanks

I'm interested in this as well...

I've upgraded my main's via 5-90 so I'm in need of a new Alt for my 01. During this cold weather my alternator has a hard time keeping up when running (upgraded Cibie headlights, heater fan above 1, rear defrost, Dirtbound triple electric fans and an upgraded stereo system w/sub) ...

I'm not afraid to do some grinding to fit an upgraded alternator (I've done it on jeeps in the past) but a simple bolt in swap would be a nice change.

The ZJ alternators require some trimming of certain areas in order to make it fit. BUT if you find a local rebuild shop that can rebuild your stock alternator they can increase the amperage for a lot less than what you can buy the ZJ alternator for and it will be a perfect fit.

I called a local rebuilder and he said he doesn't do "upgrades" anymore, because they just don't produce the numbers. Now I know this may not be the case for many, and a lot of people have had it done successfully, but that's the extent of my interaction with a local shop...

Well, I bought the alternator... At a glance it looks like it should fit fine with a little grinding, I'm sure it's the same case a s the 136A model. I gave up on fitting it because the stupid cast bracket broke when I was removing the old one. It was the bottom bolt, the threads corroded and the pressure split the bracket. Not sure who came up with the great idea of threading directly into the cast with exposed threads on the back side :twak:
Anyway, the alternator seems decent and is new not reman, but the damn box does say made in China. MFG is WPS (world power systems). It came with a sheet showing a test curve and numbers, which says 136A at the top, but it tests at 150A and Quadratec lists it as 150A...
Anybody have any comments on the field, leakage and ripple current? Not really sure what those are and if these numbers are good or bad.

The performance curve looks strange to me. I'd hope to be getting more amps than 0 @ 1000 rpms...

Could be I'm not reading this right. My biggest issues I see for charging with my 117 amp OE Alt is at idle or just off idle. Once rpm's exceed 1000 I don't see any issues. My issues are only seem to be at idle ~ 700 rpms.

That and I've never seen a Jeep 4.0 engine hit 6000 rpms...

I'm interested to hear how the install goes and your results after. Thanks for updating.

Redsnake said:

The performance curve looks strange to me. I'd hope to be getting more amps than 0 @ 1000 rpms...

Click to expand...

Alternator pulleys are usually about half the size of the crank pulley, therefore spin twice as fast as the engine.

So at idle you're really seeing about 1600-1700 rpms on the alternator which seems to be about 70A.

MoparManiac said:

Alternator pulleys are usually about half the size of the crank pulley, therefore spin twice as fast as the engine.

So at idle you're really seeing about 1600-1700 rpms on the alternator which seems to be about 70A.

Click to expand...

That makes more sense...

For me the biggest 'hit' on voltage drain I see is when I turn on my Rear Defrost while also running the heater and headlights... early morning trips to work. The voltage gauge drops f/ ~ 13.5 to near 10 volts if I'm just idling... if I turn off the rear defrost the gauge jumps back up immediately to the 13 +/- volt range.

Yeah, that data is based on alternator RPM, and not the engine RPM. I'm not too worried about idle output anyway, because I don't use the rear defroster and the stock alt kept up with my needs at idle. I just wanted some more juice for winching, and I have a hand throttle to bump up the RPMs...