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Bolt-in EA series Alternator upgrade. Nissan Maxima alt installation guide.


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does anyone know what the case size of the maxima alt is?I have an ej22 and I am looking for a bigger alt.I tried test fitting a EA series alt on the ej and it wouldnt fit because the case is bigger on the EA alts, even though they have the same bolt pattern for mounting.

 

it would be great if there was a junk yard option for a 100+ amp alt for EJ's.

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does anyone know what the case size of the maxima alt is?I have an ej22 and I am looking for a bigger alt.I tried test fitting a EA series alt on the ej and it wouldnt fit because the case is bigger on the EA alts, even though they have the same bolt pattern for mounting.

 

it would be great if there was a junk yard option for a 100+ amp alt for EJ's.

 

the Maxima alt won't work on the EJ22's, it's pretty much the same size as the stock EA82 alt, maybe even a hair bit bigger

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Considering that the 1980s wiring was done for 50/55 amp alternator, would installing 90 amp alternator burnout wires/start engine bay fire?
..a higher amp alt gives you the ability for example to add on more accessories or to have your stock set-up being provided with 12+volts from the alternator rather then have the system under heavy load being helped out by the battery...however,you will burn wires, switches if you "increase" the amp draw on any stock device that may be on the vehicle without making changes first....for example putting in 100 watt head lights when stock is 45 watt..new wireing and relays will have to added..one of many reasons to have a 90+ amp alt..
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Your problem isnt the alt.

 

Its the drop in RPM. Either something like your heater fan is on its way out and is drawing too many amps, or you simply need to bump the idle up a bit.

..over the last couple of days I believe my problem is more related to a sloppy regulator and a problem with the ECU by not providing enough voltage to the "idle control valve"... if I had a carbed vehicle, bumping up the idle would be a good simple solution..but this is a FI conversion and the idle is already set at 900rpm (150 above stock setting)...overall I am very happy to have known about this alt conversion because the car has AC and upgraded cooling fans and is great for idleing over rocky terrain..but all is not perfect..if I had to do this again I would probably buy a new alt. rather then rebuilt/reman...my observations of this morning are thus..the voltage regulator works but is sluggish to change fast enough to maintain adjustment..when cold the voltage is rock steady at 14V and will increase as load is provided..once the alt gets hot, voltage drops to 13.6V by the time the engine is warmed up..all in all very respectable, but when loaded up it will drop closer to 13V ... I will not see 14v+ again until the next day when it is cold..( it was only yesterday that I became aware that remanf. alt do not have new regulators installed..if the old one works within their sloppy specs, the rebuilders use it or replace it with a newer inferior part) ...the "idle control valve" gets under 12V, and is unable to maintain steady voltage to control a steady idle once the electrical system is placed under a heavy demand of amps..in other words the voltage to the idle control fluctuates ,even under the slightest load...same goes for my fuel pump..wire from the ECU to the fuel pump provides only 12.33V with engine running ..not enough when the system is placed under load..ran a wire with a new relay and used the ecu just as a trigger and now it works perfect...when I get around to it, I will exchange the ECU and see what happens.. Edited by Petersubaru
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Yep, like I said, the alt isnt your problem.

 

Sound like you are on the right track though. You have some tuning to sort out to keep the idle high enough.

 

And really, 13V at idle with accessory load on it is just fine. Most vehicle spec a minimum of 13.5 - 14.5 at idle with NO load.

 

And normally optimum voltage output is read at 2k+rpms

 

 

That said, most rigs have an idle bump to take into consideration heavy electrical loads, to maintain proper charging voltage and keep the engine from stalling at idle.

Edited by Idasho
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..a higher amp alt gives you the ability for example to add on more accessories or to have your stock set-up being provided with 12+volts from the alternator rather then have the system under heavy load being helped out by the battery...however,you will burn wires, switches if you "increase" the amp draw on any stock device that may be on the vehicle without making changes first....for example putting in 100 watt head lights when stock is 45 watt..new wireing and relays will have to added..one of many reasons to have a 90+ amp alt..

 

So are you saying that as long as I dont change anything (lights etc) but the amp, it wont ruin anything?

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So are you saying that as long as I dont change anything (lights etc) but the amp, it wont ruin anything?
..as long as you don't install items to "draw" more amps "useing" stock wireing switches etc,..your good to go... this applies to any vehicle, new or old..
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Actually thats not completely true. A partially drained battery is a bottomless amperage pit. The battery will draw the alt at max capacity and overload the wiring. You always need to upgrade the main output from the alt to the battery even if you are otherwise completely stock.

 

GD

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Actually thats not completely true. A partially drained battery is a bottomless amperage pit. The battery will draw the alt at max capacity and overload the wiring. You always need to upgrade the main output from the alt to the battery even if you are otherwise completely stock.

 

GD

Glad you stepped in..to upgrade that stock wireing to be on the safe side ..does one just add another wire to what is already there or just replace with a single heavier gauge wire..
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Yep - a supplemental 10 AWG wire from the alt to the battery with a fuse at or near the battery is essential to insure the alt can't burn up the wiring and connections between itself and the battery.

 

If your battery is good you may never need it but the potential to overload 55 amp sized wire with 20+ year old connections is there even if you get away with it for years without a failure. It's really not that hard to install either.

 

GD

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Yep - a supplemental 10 AWG wire from the alt to the battery with a fuse at or near the battery is essential to insure the alt can't burn up the wiring and connections between itself and the battery.

 

If your battery is good you may never need it but the potential to overload 55 amp sized wire with 20+ year old connections is there even if you get away with it for years without a failure. It's really not that hard to install either.

 

GD

will do ..thanks

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  • 2 weeks later...

my utmost apologies if this is an already answered question: i am currently parting out a 92 maxima vg30de (quad cam). i noticed GD, that you said any sohc vg30 alt will work on my ea82. am i correct in assuming that in fact the alt in this car will not work for me? thanx for your time and again,sorry if i missed an earlier post on this.

 

 

RV

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Yep - a supplemental 10 AWG wire from the alt to the battery with a fuse at or near the battery is essential to insure the alt can't burn up the wiring and connections between itself and the battery.

 

If your battery is good you may never need it but the potential to overload 55 amp sized wire with 20+ year old connections is there even if you get away with it for years without a failure. It's really not that hard to install either.

 

GD

 

The fuse is only needed if the run of wire is longer than 18", to be technical. The fuse will not hurt anything if added and it's always better to be safe than sorry, but if the run is 18" of less, I don't bother with the fuse since it's not really needed and is just a wasted expense and something else to corrode and fail or at the very least it's something you need to check every so often. Either way it's something else to check/fail. Even the "nice" fuse holders will eventually corrode and start to fail at some point. I spent $50 on a "nice" fuse holder only to have it fail within 3 years. Circuit breakers have less of a problem with corroding and failing, but they still will, and they cost more money but are much better overall than a fuse holder. I will never install another fuse/fuse holder under the hood of my car again. Only circuit breakers.

 

I run circuit breaker for my stereo in my car with an upgraded alt but no breaker/fuse from the alt to the batt since the run is about 18", and I have had no issues for the last 3-4 years :)

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  • 4 months later...
Yep - a supplemental 10 AWG wire from the alt to the battery with a fuse at or near the battery is essential to insure the alt can't burn up the wiring and connections between itself and the battery.

 

If your battery is good you may never need it but the potential to overload 55 amp sized wire with 20+ year old connections is there even if you get away with it for years without a failure. It's really not that hard to install either.

 

GD

 

im assuming a 125 amp fuse? or should it be smaller?

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my utmost apologies if this is an already answered question: i am currently parting out a 92 maxima vg30de (quad cam). i noticed GD, that you said any sohc vg30 alt will work on my ea82. am i correct in assuming that in fact the alt in this car will not work for me? thanx for your time and again,sorry if i missed an earlier post on this.

 

 

RV

 

Update: having not received an answer to my previous query i ventured forth on my own. answer: no the alt from a vg30de will not work. upon further noodling ive now seen that GD in fact said "sohc", the DE is DOHC.......

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thanks for the info GD also did we ever get a final conclusion on whether or not this was bolt on for the xt turbos? and to clairify according to the FSM they are 55A stock also the alt size difference is for hood clearence issues same reason the XT6 one is wonky. ill be trying this while i change out my oil pump this weekend and IF there is modification nessisary for the XT turbo ill document it here if thats alright with GD

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"The fuse is only needed if the run of wire is longer than 18", to be technical."

 

Incorrect. The length of the wire has absolutely nothing to do with using a fuse or not. You add an electrical accessory, you add the appropriate sized fuse on that circuit unless it is hooked to a correctly fused supply. Distance makes no difference. A short to gnd can occur at the source or inside the component, especially with the alt or batt. You can have a short in the windings, the regulator or inside the batt. YES, inside the batt! I see 3-5 of these a year. Degree in electronics and 20+ years in automotive electrical and electronics. There is NO correct or logical argument for not using a fuse. You wanna ruin components or burn your car to the ground, be my guest. It's not worth it. Oh, and the corrosion.... Put dielectric grease on all your connections. Problem solved. Going on 15 years with my utility trailer with no issues. :D

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Incorrect. The length of the wire has absolutely nothing to do with using a fuse or not.

 

Wrong dude.

 

Wire length and wire size are both used when determining the capacity of a wire.

 

Length most certainly matters.

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