Author Topic: Engine Bay Electrical Revamp  (Read 2315 times)

jaccox

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Engine Bay Electrical Revamp
« on: February 17, 2018, 11:51:38 AM »
Lets face it most people who buy Montero's for camping/wheeling/overland purposes plan to have quite the electrical demand put on their charging system. Well I haven't seen much on this forum about electrical upgrades or no-no's, so I figured I'd get the ball rolling on the topic. Let it be known my experiences are only with my very own 99 montero so Gen2 can take all I have to say to pretty well match up to their chassis. For the rest of you folk it should be quite similar maybe a few variations that other members with some more experience with those chassis can chime in with some knowledge. I want to cover Lighting/alternator/battery and maybe add on to that as my boredom grows at work. I will provide links to products I have used along the way of my trial and error of owning and modifying my truck.

Lets start with the Alternator and work our way out from there, since it's the heart of the operation.
So you got your montero and you're quickly realizing how amazing these gems are. Well it starts to creep in the back of your head all the things you want to put on your truck to make it flashier and more reliable off the pavement (winch, lights, dual battery, chargers for all your forms of communication). In terms of the Gen2 our trucks are equipped with a 100 amp alternator from the factory, which is really really good for the time period they were released in. Haven't looked it up but I'd be willing to bet that trumps factory jeep and 4runner outputs of the same period, because Mitsubishi wasn't lacking in engineering at these times. You still are certain you will exceed the parameters of the 100 amp output and want more? Again from the perspective of gen2 your alternator hot wire is only an 8awg wire and the routing of this wire can easily be goofed during regular maintenance in regards to where it passes near manifolds and EGR (especially on the SOHC in my case). 8awg is enough to carry the 100amp of the factory wiring but after many years of heat cycles wires chaff and rub on things and break through the protective covers of your factory wires. Lets consider the wire to be the hallway that directs your people (amps in this case) to their destination (the battery in this case), and think if it is easier to move 100 people down a 4' hallway or easier to move them down an 8' hallway. Makes sense that the wider hallway would make travel much easier right? Well Mitsubishi designed our charging systems to be perfectly suited for the 100 amp max and sometimes the congestion of the 8awg can be a bit of a hinderance and can make your alternator struggle to get all the amps its making to the battery. The less an alternator has to make max output the less heat it will generate, and heat aside from oil soaking is a leading cause of alternator deaths. In my case I chose to go up in alternator output capacity to be able to have the more than needed in reserve for when i really need to use it. I will STRONGLY suggest that before you ever replace your alternator that you first off upgrade you wiring of the charging system. I did a ton of research on this before taking any action, and I read countless threads on off road forums and even competition sound system threads where people are searching for every amp possible in their charging systems. In the world of sound systems a common upgrade is something they refer to as "the big 3", they essentially upgrade all their grounds and charging wires correlated to their alternator and battery. I cannot urge you enough to do your own research on this as well. In my application I chose to upgrade all of my wires with 4awg (which is rated for up to 150amps) as well as leaving all stock wiring in place as overkill. Electricity is like water in that it will take the path of least resistances so leaving the stock wiring gives the system more breathing room (but please remember this also leaves more contact points for tracking down gremlins if you ever end up having them). I used the pre-made kit from CEautoelectricsupply (tons of knowledge on this website as well as the most top notch products) out of the wonderful land of AZ that I will link below. I strongly suggest this kit for anyone planning to do this, and the most important piece of this kit is that it comes with an extra ground for proper grounding of the alternator. Everyone always stresses the upgrade of the hot wire but the ground doesn't seem to gain as much attention. All alternators ground through rear portion of the case, so in a montero that means from the rear case out to the back most ear then to the face plate of the timing assembly and through the engine block and out of the ground wire/strap at the AC bracket and to the frame. Now that is so many transition places for your charging system to have to pass through just to acquire a proper ground is it not? I mean look at the different qualities of metal the current has to pass through to make the loop to your battery to make it possible for the alternator to do its job. This kit comes with a ground wire that goes directly from the rear of the alternator directly to the negative post on the battery, and that eliminates so much of the struggle of completing the loop for your alternator. The Another thing you will hear in the montero community is OEM alternator or you will have all kinds of problems. Well I've never had the pleasure of having my OEM unit as I'm sure it died an oily death long before I got the truck, but I can tell you that yes aftermarket units will be far from the quality of the OEM but they are not as bad as everyone would have you believe. I am solely convinced that aftermarket units work perfectly fine when you provide them this upgraded ground included in the kit I suggested. The kit also comes with more than enough hardware to get any job done as well has highly detailed instructions for installation. I will say that instead of drilling and tapping the rear of my alternator case i simply ground down my rear tab to fit the ground between the case and tab on the timing cover, I can snap pics and post them later if need be. Now most will say to have your OEM unit rewound for a higher output, which I can say will be your best bet for upgrading the output, but I didn't have an OEM to get that done to and live in the Southeast where they are more than scarce to find. I decided to go a less traveled and budget friendly route and purchased a 150amp aftermarket unit I found on wonderful Amazon by a company called Lactrical out of California. It is an under drive pulley so a different size belt is required and I can provide that info later as well if someone is interested in this route as well. I asked and this alternator is to produce around half of the max output at around 1200RMP and the full 150 at around 2400RPM which knowing the montero most of you driving RPM's are dead on in that range and even when offroad in low range you hover around those RMP as well.

Here is the wire setup I used, I chose the longest one offered I believe 5': https://ceautoelectricsupply.com/charging-system-upgrade-kits/
Here is the alternator I am currently running: https://www.amazon.com/gp/product/B00AY2A3XS/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1
1999 Montero. 33x10.5x15 General X3's. 4.90's w/rear locker. Full armor. ADD idler arm. ADD 1.5" complete lift. Siberiean Bushings everywhere. 150W alternator with upgraded 4 AWG leads and grounds. 2nd Battery in the rear for camping stuffs to come.

jaccox

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Re: Engine Bay Electrical Revamp
« Reply #1 on: February 17, 2018, 11:56:10 AM »
Alright lets move on the the battery portion of this rant. The battery is a bit like the lungs of the operation under the hood. For the gen2 peeps just do yourself a favor and upgrade from your group 34 stock sized battery to a group 27, the battery tray is perfect for this sized battery. I've seen a few pics of some trimming the battery tray and fitting two group 34s into the tray perpendicular to the way your stock battery sits for a dual setup, but a dual setup is something for an entirely different thread all-together. I'm not here to argue types of batteries, but I haven't had much experience with them as I bought a new group 27 deka hybrid starting/deep cycle and it has been nothing but wonderful to me. Not much else to be said about batteries, rule of thumb is fit the largest you can possibly get into your battery tray. The more CCA the better in my opinion, and then you can step into the realm of adding second batteries and solar if you see it fit to do so.

Finally lets talk about lights and accessories. Look at all the draws you have from your charging system and look at them like thanksgiving turkey you need to trim the fat from. From the factory Mitsubishi saw it fit for your 100amp charging system to power all the accessories equipped on your truck. They accounted for you riding with the AC fan blowing, radio jamming, hazards on while holding the brakes, windshield wipers on and at night with the high beams at idle. But for anyone looking to add other things in the form of communication devices, chargers, fridges, lights, winches, or any other electrical parasites you run the risk of taxing out your alternator and battery and shortening their lives drastically. I would urge anyone hunting to trim down the amp usage to first start with updating all of your interior lights to LED. It is simple and somewhat inexpensive with the price of LED's nowadays, and I'm sure you have a few bulbs out on your 20ish year old dash now. Now on the Gen2 i know from experience if it has a green or red filter over the light the LEDs just won't pierce through so you gotta stick with the filament bulbs. You can save quite a bit by just doing this and save your battery and alternator a lot of strain in the long run. For any LEDs I suggest checking out superbrightleds.com as they have everything you could ever imagine and they are super quality products. Another place people go to save on the amp draw is switching their headlights to LED... I know touchy subject and I can admit I went there, but alas I'm back to halogen and never ever plan to go back for personal preference. My montero headlights are leaps and bounds better than any other vehicle I've ever driven and I feel silly for even trying the LED's. I couldn't aim them the color was horrendous and glare was even worse, I lied to myself at first and got by for a few months but went back to halogen and never plan to leave again. I will say that adding relays to my headlights was also a game changer with the halogens and I would suggest it to anyone looking for that tiny bit more performance to look into it. I used a piggy back setup for a jeep and haven't had a problem in over a year and a half of using it, also check out danielsternlighting.com for any questions involving headlights/relays. Hell if it did break i'd pull over and hook it back up to the stock pigtails and be on my way. Auxiliary you can save on by going with LED vs halogen or HID, but I know some people need the heat and/or prefer old school looks. If you don't want the LED then you still have the option of doing everything i've mentioned thus far for more capacity with charging and battery to help with the higher draw. With the winch you really just want to make sure your battery is in decent condition as the winch puts a large strain on it very quickly, but seeing as how most duty cycles are relatively brief you can get away with stock everything as long as you don't have every accessory know to man on at the same time. If you need to winch for long periods just do yourself the favor of going hydraulic, again topic for another thread. If you haven't already go LED for your reverse lights. It's cheap easy and way better in every way imaginable. Just splice directly into the factory wires and mount them and you're good to go. As for all the other exterior lights I looked into replacing those with LED's and either cost was going to be far too much or the LED's just didn't perform as well as the stock filament bulbs. LED has come a long way but with something like a brake light that needs illumination in all directions its hard when LEDs are just a lot of small lights joining together and they haven't figured out how to make ones that small put out as many lumens as an equal sized stock bulb. Plus between purchasing the proper relays or splicing in new pigtails it was just a job I didn't want to undertake at the time. All in all cut down on amps where you can and splurge where you want, juggle it around and try to keep it as reasonable as you can.


Hope this long rant/informative article helps someone. I just wanted to share some of my trials and errors up to this point since I'm happy with where my charging system is at this point. This will be a great place for others to following along in the time to come, and for others to share their own discoveries and failures in this area.
1999 Montero. 33x10.5x15 General X3's. 4.90's w/rear locker. Full armor. ADD idler arm. ADD 1.5" complete lift. Siberiean Bushings everywhere. 150W alternator with upgraded 4 AWG leads and grounds. 2nd Battery in the rear for camping stuffs to come.

Crumb

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Re: Engine Bay Electrical Revamp
« Reply #2 on: February 18, 2018, 10:07:21 AM »
Dude. Well done. (Clapping hands emoticon)

S298WP

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Re: Engine Bay Electrical Revamp
« Reply #3 on: March 09, 2018, 06:14:31 AM »
Hell yeah Josh. Good write up!
So in basic summation....add the 4AWG line to the battery, while retaining the 8AWG original line. Then replace the stock ground with 4, and add the extra 4 to the timing area off the rear case of the alternator?
I know I've read on the FB group before about rerouting the stock 8AWG positive away from the intake/GET. Any insight to that?
I think I may dive into this tomorrow or Sunday. I need to get things up to par for adding my auxiliary battery in the rear.

Well done man!

jaccox

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Re: Engine Bay Electrical Revamp
« Reply #4 on: March 09, 2018, 07:57:00 AM »
Hell yeah Josh. Good write up!
So in basic summation....add the 4AWG line to the battery, while retaining the 8AWG original line. Then replace the stock ground with 4, and add the extra 4 to the timing area off the rear case of the alternator?
I know I've read on the FB group before about rerouting the stock 8AWG positive away from the intake/GET. Any insight to that?
I think I may dive into this tomorrow or Sunday. I need to get things up to par for adding my auxiliary battery in the rear.

Well done man!
I left the stock 8AWG ground in place as well and just put the new side by side with it. As for the EGR section I believe the mistake commonly made is routing it under the EGR rather than around the outside next to the brake booster. I zip tied mine to something to ensure it cannot bounce down and hit the EGR, my plastic sheath had signs of getting close to it when I bought the Monty. As for the ground from the alternator yes I ground on the rear ear of the alternator ear to sandwich the eyelet between the timing case and alternator ears, then directly to the negative terminal.
1999 Montero. 33x10.5x15 General X3's. 4.90's w/rear locker. Full armor. ADD idler arm. ADD 1.5" complete lift. Siberiean Bushings everywhere. 150W alternator with upgraded 4 AWG leads and grounds. 2nd Battery in the rear for camping stuffs to come.

S298WP

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Re: Engine Bay Electrical Revamp
« Reply #5 on: March 09, 2018, 08:01:00 AM »
Nice man.
I'd say definitely post some pics for future reference!

jaccox

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Re: Engine Bay Electrical Revamp
« Reply #6 on: March 09, 2018, 08:06:42 AM »
Nice man.
I'd say definitely post some pics for future reference!
Will do once I get the timing cover back on and everything buttoned back up. She's deeeeeep under the knife right now lol. Also when you do this upgrade its an awesome time to hit grounds with the wire wheel and a squirt of white lithium grease for good measure.
1999 Montero. 33x10.5x15 General X3's. 4.90's w/rear locker. Full armor. ADD idler arm. ADD 1.5" complete lift. Siberiean Bushings everywhere. 150W alternator with upgraded 4 AWG leads and grounds. 2nd Battery in the rear for camping stuffs to come.

jaccox

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Re: Engine Bay Electrical Revamp
« Reply #7 on: April 09, 2018, 10:52:05 AM »
After this last week's trip I put my electrical system through its paces. Between running my dual battery setup, hours of lower RPM crawling and less airflow, running the 1500watt inverter to charge all my stuff along with other people's things. Was able to run chargers and even a fan. I OBD' d my voltage for a majority of the off road portions and the charge stayed rock solid I have 0 problems whatsoever. I'm extremely happy with where things sit at this moment. Also I have the pics of my ground wire. I cut it to make it where removal is not necessary to remove the bolt from the ears but it slides in and is held in place by the pressure of alternator and the bracket. Also ignore any oil you see in this pic. I have finally fixed my cam shaft seal leak with a speedi sleeve.
1999 Montero. 33x10.5x15 General X3's. 4.90's w/rear locker. Full armor. ADD idler arm. ADD 1.5" complete lift. Siberiean Bushings everywhere. 150W alternator with upgraded 4 AWG leads and grounds. 2nd Battery in the rear for camping stuffs to come.