z24 alternator replacement/upgrade options.

[ElliotV]

So yesterday I was driving down the highway and we were having some crazy rain and I think my alternator might be having some issues now. It got splashed pretty good and the belt started squealing for a few seconds then stopped and at the time the voltage was reading just like normal at 14.1-14.4v depending on how much I had my wipers and blower cranked up. After I left my destination the belt squealed when I went from idle on the gas in neutral so I figured probably ruined the belt no biggie I will drive home and get a new one but the alternator was only charging to 13.6v at 2500rpm going down the road which is less than normal for me only having my headlights on. After that I went to a party so a few hours go by then I drive home and after I got off the highway I checked to see if the belt was still squealing which it wasn't but the alternator would only charge to 13.9v going down the highway with just my headlights on(and I have leds so they really don't draw much). I have been wanting to upgrade alternators since the stock one is only 50 amps. I know that there is a quest alternator upgrade which seems to take a bit of work to make it fit like custom brackets and they are over 100 amps which I don't really need that much and I know that it pushing serpentine belt terittory. I have seen a KA alternator swap mentioned on here before and figured it came from one of the vehicles nissan made with a ka24? I noticed that the 240sx with a ka in it uses a 80amp alternator which sounds like it would be a nice uprade for charging without getting to ridiculous and looking at pictures it looks like it just bolts right in and uses the same mounting method as mine. Curious if anyone has any insight before I start experimenting.

[banzai510(hainz)]

I think your fine myself

On my Jeep it would be higher if not driven then later its lower( i think when the battery charged up.

I would not panic yet

[ElliotV]

33 minutes ago, banzai510(hainz) said:

I think your fine myself

On my Jeep it would be higher if not driven then later its lower( i think when the battery charged up.

I would not panic yet

Not really panicking but I just don't want it to fail on me while I am far from home and have been wanting to upgrade to a bigger alternator for sound system stuff and a dual battery setup. I am leaving for vacation this weekend so I have some time to think on it since I won't be driving much more than 10mi from home the rest of this week I do know it needs a new belt though since either the one that is on t just has stretched that much or it's the wrong size cause the tension is good but it is maxed out on the adjustment.

[datzenmike]

The 240sx KA alternator has a serpentine belt pulley. The V pulley fits right on but the external fan rubs. I made a spacer but this reduces the threads the nut has for holding it on. I managed 2-3 turns on and then MIGed a small spot so it couldn't come off.

 

Now I see the KA alternator has an internal fan on the rotor so the external fan could be cut off. Didn't know this at the time. The Car KA is 80 or 90 amp. Truck KAs are V belt but only 50/60 amp

 

 

[banzai510(hainz)]

Key is making sure the one you put in is good as the orginal.

I havent been impressed with rebuilds from anywhere. its a crap shoot

[ElliotV]

1 hour ago, banzai510(hainz) said:

Key is making sure the one you put in is good as the orginal.

I havent been impressed with rebuilds from anywhere. its a crap shoot

Yeah that's seems to be the deal with some stuff I honestly can't remember if the current alternator is original I do remember that it has a pink tag on it. I started the truck up and drove it to work today and it's charging at 14.1-14.2v now so I really don't know.

[ElliotV]

2 hours ago, datzenmike said:

The 240sx KA alternator has a serpentine belt pulley. The V pulley fits right on but the external fan rubs. I made a spacer but this reduces the threads the nut has for holding it on. I managed 2-3 turns on and then MIGed a small spot so it couldn't come off.

 

Now I see the KA alternator has an internal fan on the rotor so the external fan could be cut off. Didn't know this at the time. The Car KA is 80 or 90 amp. Truck KAs are V belt but only 50/60 amp

 

 

Other than that though did the alternator bolt right in? Did you have to do anything for the connections?

[Thomas Perkins]

I use Gate belts.7365 is for the alternator/fan.Rock Auto Parts has them for 9.95.I also use a 60 amp in my  85 4x4.I also use a black magic marker and mark a line on alternate and bracket that let's me know if the  belt has moved.I also put a nut behind the tension screw with lock washer to keep alternator from moving.I have a new Nissan Alternator bracket in case I ever need one.

Edited May 22 by Thomas Perkins

[ElliotV]

47 minutes ago, Thomas Perkins said:

I use Gate belts.7365 is for the alternator/fan.Rock Auto Parts has them for 9.95.I also use a 60 amp in my  85 4x4.I also use a black magic marker and mark a line on alternate and bracket that let's me know if the  belt has moved.I also put a nut behind the tension screw with lock washer to keep alternator from moving.I have a new Nissan Alternator bracket in case I ever need one.

Will probably pop mine off and compare it it's only 8 bucks at AutoZone so if it is a little shorter that's perfect. I will probably still look at doing the ka alternator mod and experiment with my parts truck to see what fits on it so I can keep driving mine.

[Thomas Perkins]

2 hours ago, ElliotV said:

Will probably pop mine off and compare it it's only 8 bucks at AutoZone so if it is a little shorter that's perfect. I will probably still look at doing the ka alternator mod and experiment with my parts truck to see what fits on it so I can keep driving mine.

Auto Zone's belts are not good.I bought one  and it is cheaply made.Gates are the best.You get what you pay for.

[ElliotV]

6 minutes ago, Thomas Perkins said:

Auto Zone's belts are not good.I bought one  and it is cheaply made.Gates are the best.You get what you pay for.

I haven't had any issues with them before and usually I can get a Continental version of the belt.

[banzai510(hainz)]

I got a vatozone belt for my Toyota pick up said made in India 9$

then went to Napa for my other Toyota same velt 6$ made in USA GATES  what the Fuck!!!!!!!!!!!. Bought American

[Thomas Perkins]

2 hours ago, banzai510(hainz) said:

I got a vatozone belt for my Toyota pick up said made in India 9$

then went to Napa for my other Toyota same velt 6$ made in USA GATES  what the Fuck!!!!!!!!!!!. Bought American

Napa and advance sell the same parts.Gates is heavy duty.Their are fake parts out there.

[Thomas Perkins]

Auto zones belts are thin and stretch.

[Stinky]

I went through this.

 

I decided to just replace my stock alternator w/a stock alternator.

 

I got an Autozone unit...after a few years, maybe as many as 5, they replaced it.

[Stinky]

OH....you can change pulleys on an alternator.  Once you break the nut loose, no problem.

[datzenmike]

On 5/22/2024 at 2:01 PM, ElliotV said:

Other than that though did the alternator bolt right in? Did you have to do anything for the connections?

 

Well that's the thing... because the V pulley had to be shimmed it didn't line up with the other's so I ground down the block mount. I bet if you cut off the fan blades (you don't need them anyway) it likely will fit.

[ElliotV]

19 minutes ago, datzenmike said:

 

Well that's the thing... because the V pulley had to be shimmed it didn't line up with the other's so I ground down the block mount. I bet if you cut off the fan blades (you don't need them anyway) it likely will fit.

I will probably have to experiment with that then my parts truck doesnt have ps pump on it so the alternator is right there will probably work on making it work on there without having to grind anything on my truck then just translate it over. Mainly curious about whether or not the connectors need changed.

[bottomwatcher]

Connecter "T" shape did change over the years but standard spade connectors plug right into the back eliminating the need for a special shaped plug. Just make a couple of jumper wires with male spade on one end and female on the other and you can run whatever bolts up.

Edited May 24 by bottomwatcher
Spelling

[datzenmike]

The plug certainly changed in '86.5 with the D21 Hardbody. I think it may have changed with the Z24i in April '85 but I can't find it. Tommy has an '85 carburetor, what does he say?

[ElliotV]

13 hours ago, datzenmike said:

The plug certainly changed in '86.5 with the D21 Hardbody. I think it may have changed with the Z24i in April '85 but I can't find it. Tommy has an '85 carburetor, what does he say?

Maybe mine is the same then but I don't remember what my build date is.

[Thomas Perkins]

I have a alternator plug if you need one.You can have it for free.Do you want me to take pictures of it.It is like new.

Edited May 25 by Thomas Perkins

[datzenmike]

This style

 

[ElliotV]

30 minutes ago, Thomas Perkins said:

I have a alternator plug if you need one.You can have it for free.Do you want me to take pictures of it.It is like new.

Might have to take you up on that if I need one. I'm leaving for vacation tomorrow but when I return I will probably start on the alternator upgrade and add in the charging system for the deep cycle battery I plan to put under my toolbox to run my air compressor and any other extra stuff.

 

 And Mike my door tag says 4/85 so it might have the newer connector.

Edited May 25 by ElliotV

[Thomas Perkins]

I believe this came off  my 50 amp old alternator and my fitting connects onto the big end and little end goes into alternrltor.On my 60 amp alternator my fitting on mine truck goes into the alternator and this cable is not used on my 60 amp alternator.

Edited May 25 by Thomas Perkins