70A alternator upgrade for 1990+ LJ7x?

GTSSportCoupe · Feb 27, 2019

I keep having to rebuild my OEM 55A alternator every couple of years. I seem to be overheating the stator and blowing the rectifier. I tow a camper trailer every summer. It's setup so that the camper battery recharges while I'm driving. I'm guessing that this additional load (plus all the extra lights, electric brakes etc.) is too much for my alternator.

So, as it turns out, there was a 70A alternator offered on the 2LTE in the JDM cars the motor came in. This 70A alternator can be bought for a reasonable price here: Kuhner Premium Diesel Alternator 12V 70A - Round Plug

Has anyone tried this alternator in their LJ7x cruiser? Wondering if anyone has experience with it. Hesitant to drop the $$ without some sort of review. From the Megazip website, it appears this alternator is longer (to accommodate the larger stator).

CharlesHS · Feb 27, 2019

Sorry no experience with Kuhner….
My LC also came with a 55A alternator, but the PZJ doesn't have much of an electrical load until the winch is used.
I used ToyoDIY to find the factory part number and cross reference all the other vehicles that use that alternator.
I found there was a 80A alternator as an option and purchased a new ND alternator from Rock Auto.

GTSSportCoupe · Feb 27, 2019

CharlesHS said:
Sorry no experience with Kuhner….
My LC also came with a 55A alternator, but the PZJ doesn't have much of an electrical load until the winch is used.
I used ToyoDIY to find the factory part number and cross reference all the other vehicles that use that alternator.
I found there was a 80A alternator as an option and purchased a new ND alternator from Rock Auto.

Do you have a part number for the alternator you bought? 80A would be even better!

CharlesHS · Feb 27, 2019

27060-17170 which cross references to a wide variety of LC vehicles 01/1990 - 12/06 .

GTSSportCoupe · Feb 27, 2019

CharlesHS said:
27060-17170 which cross references to a wide variety of LC vehicles 01/1990 - 12/06 .

Thanks! Is it hard to mount the vacuum pump on the front? Or did you install a different vacuum pump?

CharlesHS · Feb 27, 2019

GTSSportCoupe said:
Thanks! Is it hard to mount the vacuum pump on the front? Or did you install a different vacuum pump?

Mine truck does not have a vacuum pump attached to the alternator...
According to the picture of the vacuum pump installed on my PZJ75 (29300-17010); the pump appears to be driven directly off the engine. I would need to look at the engine to see exactly where the vacuum pump is located.

GTSSportCoupe · Feb 27, 2019

CharlesHS said:
Mine truck does not have a vacuum pump attached to the alternator...
According to the picture of the vacuum pump installed on my PZJ75 (29300-17010); the pump appears to be driven directly off the engine. I would need to look at the engine to see exactly where the vacuum pump is located.

Ahhh, didn't realize you had a PZJ75. Yeah, the L series has no vacuum pump on the engine block like the PZ and HZ.

Sounds like the 70A is still my best bet then.

GTSSportCoupe · Sep 16, 2019

Thought I'd update here. The vacuum pump on my OEM rebuilt 55A alternator was starting to make some very unhappy noises on morning cold starts. So I broke down and bought this alternator. Price was really quite reasonable thanks to the hurting british pound. I installed it on Saturday.

Alternator (70 Amp) for TOYOTA LAND CRUISER 2.4L Turbo Diesel - 5 door - 1/1990 to 5/1993

A Replacement part. Complete with fixed twin pulley and vacuum pump.Voltage 12Amperage (AMPS) 70Plug code 24Note.

www.milneroffroad.com

The body is substantially longer than the original, but I can say the alternator fit well. It does come within a few mm of the oil feed fitting on the engine which feeds oil to the vacuum pump.

The only issue was my original alternator has a round plug, but the new one was oval. I swapped the plug/regulator between the two which was simple and seems to work just fine. I did have to trim the cover a bit (soft aluminum) to fit the round plug.

This swap was a great investment. The extra current is very noticeable, and my voltage gauge doesn't dip at idle with high electrical load anymore. I think I've got better vacuum too, as my brakes feel much better than they were. I think the extra current will be good when I tow (charge) my RV next summer again too.

Some pictures: