Yes, all good points. I recognize the dual battery set up needs to be planned. My truck is a 1992 so I have to be careful I'm planning right. I already have the spare battery tray and Ive figured out the Blue Sea gear I need. I hadnt considered the wires from the alternator. I'll add that into my list. Thanks for taking the time!
Upgrading stock alternator to 130/150 amp
- Thread starter Photoman
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Yes, all good points. I recognize the dual battery set up needs to be planned. My truck is a 1992 so I have to be careful I'm planning right. I already have the spare battery tray and Ive figured out the Blue Sea gear I need. I hadnt considered the wires from the alternator. I'll add that into my list. Thanks for taking the time!
Hello everybody.
I just installed this excellent product from @Photoman he was super help full with all my questions and was a perfect fit.
I have a question that maybe som one can answer me.
Installed is the 150Amp alternator from a Sequoa, I have a dual battery system (2 yellow top Optima) controle by a Bluesea AL-MRC (highly recommended). I also have a Ironman dual battery display that shows me the volts for the batteries, its a simple one so its just lights with a specific voltage under each one.
Here goes my question. With the stock alternator the voltage was always over 14.1 volts, with normal driving and night driving with my lights on, it rearley went under 14.1 volts during normal car use.
Now with the 150Amp alternator when i start the car its over 14.1 Volt and then after a couple of minutes of driving around (the car already warm and normal idle) not the voltage stays at 13.8 Volts, unless im cruising at about 3000RMP. but its mostly at 13.8Volt
Funny thing is during the first 3 min of the car when i turn it on, on idle (700RPM) it sits over 14.1 volt and then after that time at the same idle not it sits on 13.8Volt
I was reading that this Alternators have a voltage regulator that lets it give the voltage the batteries actually need, but it seams odd since the old one was just at full blast all the time, maybe its just a better technology because the symptom does seem like a switch changes from over 14.1 to 13.8 Volt.
Im just concerned that is not that when the Alternator gets warm it starts lacking in performance.
ALSO, If any one has any question on the install or want to see pics of the set up im more than happy to post them, I also put a 150amp relay on the instal for security and the car is supercharged to i can show how to fill everything in the tight space.
I just installed this excellent product from @Photoman he was super help full with all my questions and was a perfect fit.
I have a question that maybe som one can answer me.
Installed is the 150Amp alternator from a Sequoa, I have a dual battery system (2 yellow top Optima) controle by a Bluesea AL-MRC (highly recommended). I also have a Ironman dual battery display that shows me the volts for the batteries, its a simple one so its just lights with a specific voltage under each one.
Here goes my question. With the stock alternator the voltage was always over 14.1 volts, with normal driving and night driving with my lights on, it rearley went under 14.1 volts during normal car use.
Now with the 150Amp alternator when i start the car its over 14.1 Volt and then after a couple of minutes of driving around (the car already warm and normal idle) not the voltage stays at 13.8 Volts, unless im cruising at about 3000RMP. but its mostly at 13.8Volt
Funny thing is during the first 3 min of the car when i turn it on, on idle (700RPM) it sits over 14.1 volt and then after that time at the same idle not it sits on 13.8Volt
I was reading that this Alternators have a voltage regulator that lets it give the voltage the batteries actually need, but it seams odd since the old one was just at full blast all the time, maybe its just a better technology because the symptom does seem like a switch changes from over 14.1 to 13.8 Volt.
Im just concerned that is not that when the Alternator gets warm it starts lacking in performance.
ALSO, If any one has any question on the install or want to see pics of the set up im more than happy to post them, I also put a 150amp relay on the instal for security and the car is supercharged to i can show how to fill everything in the tight space.
Cruiserdrew
On the way there
Sounds normal. I think there is some temp compensation built into most Toyota alternators.
I have the same 150 A unit, it usually runs in the mid 13 V range, I don't think I have ever seen 14 V. With the output of this alternator it doesn't take long for your battery to reach full charge and the voltage to drop off a bit. Wow, dual batteries and supercharged, that is a full engine bay.
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The Sequioa 150a alternator was a direct-fit (including square connector) on my 2003 LX470. I didnt need to buy the connector or pins. Just an FYI.
Could it be the higher alternator amperage output at low engine rpm is requiring just a bit less voltage than the stock alternator? The more likely cause is a different voltage regulator within the new alternator.
Thanks all for the replays. I have had a good experience with the alternator. I have a problem but it's on me that one of the batteries is not charging well. So I got a second one and that's why I put the dual battery Sistem. I noticed after a month of use the Auxiliar baterry(the one that wasn't charging and I Thoight I fixed) is not lasting long while camping with the alternator on.
So I checked and the bad battery as not letting the good battery charge.
Took both out. The newer one charged correctly with the NOCO charger. The old one charged but lost voltage over night. Down to 11.56V. Tried several days and it never worked.
So now I only have one battery hooked up and the alternator battery is working great. Charges up to 12.9-13.1V after I turn the car off.
Now I'm trying to figure if I should buy another optima or try a different AMG battery. My oddissey or similar. Any thoughts are welcome.
So I checked and the bad battery as not letting the good battery charge.
Took both out. The newer one charged correctly with the NOCO charger. The old one charged but lost voltage over night. Down to 11.56V. Tried several days and it never worked.
So now I only have one battery hooked up and the alternator battery is working great. Charges up to 12.9-13.1V after I turn the car off.
Now I'm trying to figure if I should buy another optima or try a different AMG battery. My oddissey or similar. Any thoughts are welcome.
Worth noting that most aftermarket alternators are far too tightly wrapped in too-small housings, achieve their supposed output at RPMs these rigs will never see, and tend to overheat and burn out prematurely. Also worth noting is that heavy duty Application OEM alternator set ups often use two standard size alternators rather than one huge one.
As to AGM batteries, they require a very specific charging routine if they are to reach maximum performance and lifetime. Very few companies make chargers capable of properly tending to these batteries. Unfortunately, Battery minders and such just won't cut it. Without a proper charge every 60 to 90 days, AGMs literally begin to slowly die the moment you start using them. Make no mistake, they will kick ass while they live. But they'll live longer with proper charging
I see. But what would be a proper charger in the car that works with the alternator? The NOCO I have has a special routine for this specific baterry but I never take it out of the car unless I really drain it.
To my knowledge the only chargers that work in-vehicle are very spendy, and sold into law enforcement and first-responder markets. So what you'll likely wind up with is something you plug in at home and attach to the battery after disconnecting it. (Which saves you lifting an 80-pound battery twice.) Last I heard, Odyssey was working on one, to be built by (if memory serves) Pro Mariner. Somewhere on the Odyssey site is a list of approved chargers for specific batteries. The biggest Odyssey you can fit is the 31M-PC2150 (look it up here; needs to be slightly modded to fit), so you want a charger that can handle that. Most can't, and your alternator can't properly charge it either. Ideally, you want a charger that will blow fuses before electrocuting you. Just in case.
Pro Mariner is an excellent brand, though most of their appropriate models are designed to be hard-mounted in boats. I had someone make a custom charger with jumpers and fuses, based on one of their boat models. It does only one thing: charge these batteries.
Maybe a little late but with the battery charging at 13.8 volts vs. the 14.1 volts, (and on my really old cars 15.6 volts), this is why batteries last longer. Charging at a higher voltage "wears them out" quicker, but the older batteries were smaller and needed to charge faster to be up to 100% so when you made that short hop to the store it would have enough volts to start the car. Long ago, a battery with 300 amps was a big deal!
Cruiserdrew
On the way there
Completely wrong @hikermike
Batteries need to be FULLY charged to live the longest possible life. Full charging slows sulfation. Charging at 13.8 volts is marginal to fully charge a battery. About 14.4 volts is nearly perfect but most of our Toyota's don't do that either, and even then at 14.4 volts it takes an hours long absorb stage.
Though I agree, charging at 15.6 volts is too much.
I really hate to start this again, but after doing this upgrade my idiot light is on. I can't find an additional white wire, am I missing something? Any input?
- Thread starter
- #375
Sorry, I just saw your post. If the wiring was still stock, the wire that goes on the "B" alternator post has two white wires crimped in the connector. When you put the stock "B" alternator connector back on you were connecting both white wires so that part should be good. I would double check the small wires to make sure they are in the correct places. A couple folks ended up with them in wrong. Post #24 on page 2 has some pictures. If that is correct, to test the alternator, I would start the cruiser and have someone rev it to 1800 rpm's or so. Put one lead of a multi meter set to volts on the alternator "B" post and the other lead touched to the engine block for ground. The meter should read .5 to 2 volts above the static battery voltage. Somewhere from about 13.6 to 14.4 volts.
I am assuming a new 2 gauge or 4 gauge wire was run from the "B" post through a fuse to battery positive.
Bill
I am assuming a new 2 gauge or 4 gauge wire was run from the "B" post through a fuse to battery positive.
Bill
Thanks Bill, I thought about emailing you but I didn't want to bother you. I bet the wires are switched. I bought the whole set up used from a guy and I tried to copy his wiring but I may have got it wrong or maybe he did (the plug still had 80 wires attached) . As always, thank you for your help. I have been waiting to do this for about two years and bought a pulley from you. Everything has gone very smooth. Yes on the #2 wire from b to positive.
what is the secret to depinning connectors for the swap? I am poking around with a small screw driver and pick with no luck and dont want to break the connector.
NLXTACY
Wits' End
If its a screwdriver its too large. Needs to be 1mm x .6mm
its like a jewlers screw driver...slim. fits in the slot but I am not really sure how to release it...
NLXTACY
Wits' End
Here is a Metri-pack terminal which is similar. There is a tang down the center that needs to be pushed flat with the tool
