1982 FJ40, installing a 120 amp alternator and bypassing stock voltage regulator........ (1 Viewer)

[ColdTrails]

I have what I think is a stock alternator on my 1982 FJ 40, but it doesnt keep up well if I wanna run AC, lights etc, not to mention winch. My question, how difficult is it to bypass the factory voltage regulator? I have bought a new 120amp alternator that is a direct fit. Any help would be appreciated.

 

[hobbes]

@Coolerman built a bypass for my 1974 when I went to a 1987 alternator.

Lots of info in this link: Alternator altering

Coolerman’s website: Cruiser Wiring

That’s a lot of amps.

 

[ColdTrails]

Great!

Thanks

 

[Living in the Past]

Have you have the alternator out to verify is putting out require amperage? Would think will A/C you would have the 50 amp and not the 40 amp were are the two I show for your model. Winch I can see being a problem but electrical system operating correctly would think could keep up.

Are you doing long hard pulls with your winch? If so would look into dual oversize batteries. Heavier alternator will help but still won't keep up with the draw from a winch for very long. Once the voltage drops the winch motor heats up only compounding the problem.

 

[ColdTrails]

My alternator is a stock 40 amp, and is working. When I shut the engine off with AC on its slow on starting. I rarely use the winch but want the extra HP. Im a Texas guy but live in Bali and island hop on the ferrys here. These islands have few repair shops and mostly mom and pop type.

Last week I was traveling in West Java and my cruiser shut down in the middle (and I cant speak Bahasa so Google Translater is amazing) of no where. Turned out to be the electronic ignition inside the distributor. About 8 hours later at 2am I was installing original points, condensor etc to get back on the road. It was a real nightmare finding the kit.

Not sure I will ever go back to Electronic Ignition unless I can keep a complete spare in the back of the cruiser which is a completely different topic. Points are so easy, so what is the advantage of Electronic Ignition over points?

Thanks for your insight in helping me

 

[hobbes]

Can your ammeter handle 120 amps? What happens to the ammeter and wiring if that alternator goes to full output?

To answer your question on the Electronic Ignition, generally the 1981 to 1987 dizzies (NA market years) are considered the cream of the OEM crop. From @Coolerman website again: Dizzy FAQ. The NA ones assume NA emissions, so as the emissions are removed it is generally recommended, though not necessary, to get them recurved.

 

[ColdTrails]

The local shop says it can handle. I hope it can. These guy are Bali Jeep one of the better shops around bc not many exist.

This cruiser is SE Asia 1982 FJ40 with no emissions (Im American). Been living on the islands here for a few years.

I appreciate your reply. I hope the alternator doesnt go full bore!

 

[Solace in Solitude]

How often do you expect to run the AC and the winch simultaneously?

That’s a lotta amps... have you considered adding a 2nd battery and an isolator, to allow the new alternator to charge both batteries?

That would give you a bit of a failsafe and you could wire the winch to the 2nd battery... along with other accessories.

I wouldn’t give my DUI up for anything... I carry spare DUI modules.

A lot of people seem to talk up points, for potential EMP events... but, points won’t work either when you can’t buy fuel.

Good luck out there!! Sounds fun!!

 

[ColdTrails]

Probably never to be honest, in regards to running winch and AC together.

Where would I install a 2nd battery? Great idea but your thoughts?

This is a really nice cruiser. I would never take it through the brush like I used to do with the scouts and broncos in Texas. The winch is really for emergencies, such as when we park and camp on the beach here. The sand here will pull u down even though I'm running 12" wide 33's.

Thanks

 

[ColdTrails]

I was at the GM Power this morning. Its an incredible Cruiser custom shop and they do things right, so many sweet cruisers.

 

[Solace in Solitude]

Probably never to be honest, in regards to running winch and AC together.

Where would I install a 2nd battery? Great idea but your thoughts?

This is a really nice cruiser. I would never take it through the brush like I used to do with the scouts and broncos in Texas. The winch is really for emergencies, such as when we park and camp on the beach here. The sand here will pull u down even though I'm running 12" wide 33's.

Thanks

I can’t tell you where to install a 2nd battery, I have no idea what’s under your hood.

Adding a second battery may be as simple as installing a dual battery tray and wiring it in... or may require moving things around to make room under the hood.

Some have installed a second battery in the back... if it were me, I would want both batteries under the hood.

There are a number of threads, related to dual batteries and alternator upgrades... just search them out. Unfortunately, the two FJ40-specific examples, in “Cruisertech” now point to available domains (@Poser )... the articles are no longer available.

I don’t even know if you really need a second battery, or a higher output alternator.

I don’t have AC, but a number of members do and I doubt they are running 120amp alternators. I’m more inclined to believe your current alternator may be failing... or your voltage regulator (internal or external??) needs adjusting.

@GA Architect and @Honger come quickly to mind... both have AC. Rick and Joel: did either of you upgrade your alternator, when you added AC? To what?

Be very careful how you add that 120 amp alternator... don’t use the old harness wiring... don’t chance burning your truck down.

@Josie'sLandCruiser has great advice in post #7 in this thread —> Alternator conversion options for 78 FJ40

Carefully read @Cruiserdrew’s excellent insights, in post #16, of the thread above, as well.

@Coolerman can provide excellent insights, if he has time. He also sells oem (or near oem connectors, wiring, fusible links, etc.

Bottom line: be very careful that any associated wiring changes are done correctly and are properly protected... you have a very nice 40...

Good luck!!

 

[Honger]

I did not upgrade my alternator with the addition of the AC. I remember evaluating the current draw on the AC blower motor and figuring that I was okay with stock. This thread has me thinking more about the idea of upgrading though. Now that I’m in the States there are more upgrade options...

You are gonna have to bypass your voltage regulator and ammeter... the threads Danny linked too are the right place to start.

Do you have a build thread I’ve missed?

 

[Living in the Past]

Where would I install a 2nd battery? Great idea but your thoughts?

Yours being a RHD not sure. On LHD I've seen a larger battery box option that puts two batteries in line. Also seen where a second battery was mounted on the opposite side of of the engine compartment. But if you rarely use the winch may not be worth the effort. Would not install one for lights and A/C. Would never run without a voltage regulator. I've had a original Nissan Pathfinder that the voltage regulator was going out while driving on the highway. Turned on everything I could that would draw power and slowed down to get home. On a nice day if your windows are down and lights are off what going to happen of all that amperage your 150 amp alternator is producing.

 

[GA Architect]

@GA Architect and @Honger come quickly to mind... both have AC. Rick and Joel: did either of you upgrade your alternator, when you added AC? To what?

I still run the original OEM alternator. However, it was reconditioned/rebuilt a few years back.

 

[Solace in Solitude]

My guess for a while finding fuel will not be a problem. All the vehicles full of electronics won't be needing the fuel in their tanks. Early crude vehicles will be the ones moving. Guessing the simpler the easier to keep running. Don't think passing emissions would be a issue.

We disagree

Unless you are planning to steal fuel from other vehicles, or poke a hole in a fuel tanker... good luck locating an old fashioned, manual pump fuel station.

I’m not an EMP expert, nor do I concern myself with the possibility. But, many seem to worry.

If an EMP event occurs, it will likely knock out all things electronic. By “knock out”, I mean “destroy”.

Who knows what we would have left?

No access to money... no working computers, networks, atms, etc.

No where to spend any money you have available... except drug dealers and stores, that revert to paper tabulation, until they run out of merchandise.

No access to running water, electricity, etc.

My Sisters are cheering for what they envision as end-of-days and are trying to get me to repent my sins and prepare to shed my “earth suit”.

I’ve tried to convince them that I’m more inclined to welcome extraterrestrials.

But, they keep trying...

Hijack over. Sorry!!

 

[hobbes]

The gas stations are dry in a few hours around here if a hurricane threatens. The siphon trick isn't gonna last long. It isn’t exactly a secret.

 

[Solace in Solitude]

I seem to have struck a nerve!!

If you plan to siphon, why not have fun with it.

I frequently use one (for gas and one for water) of these... they work really well!!

Amazon product ASIN B07C5RVT4W
Just insert the metal end into the siphonee (source) and the tube end into the siphoner (receiver), then grab the tube, just outside the siphonee and make a few mastabatory motions (to prime it), then relax and watch it transfer about 3.5 gallons of gas per minute.

Of course, your level of success depends entirely on the quality of your priming technique.

 

[ColdTrails]

I did not upgrade my alternator with the addition of the AC. I remember evaluating the current draw on the AC blower motor and figuring that I was okay with stock. This thread has me thinking more about the idea of upgrading though. Now that I’m in the States there are more upgrade options...

You are gonna have to bypass your voltage regulator and ammeter... the threads Danny linked too are the right place to start.

Do you have a build thread I’ve missed?

The ones Danny sent is all. I plan to bypass the regulator

 

[ColdTrails]

Finally finished the 120 amp alternator install on the stock 1982 FJ40 today. I can say it went flawless, started up and charged at 14.5 for a few minutes then dropped to 13. No fires, smoke or anything.

Now when I turn on the AC, lights etc the engine never pulls down with the extra load. Gonna take the ferry to Lombok in a few days which is a 4 hr journey from Bali. Cruise around that island for a month before taking the ferry back west to Bali, then 4 hr drive to gillamanook then ferry again to Java 1 hour where the pretty girls live.

 

[Living in the Past]

Finally finished the 120 amp alternator install on the stock 1982 FJ40 today. I can say it went flawless, started up and charged at 14.5 for a few minutes then dropped to 13. No fires, smoke or anything.

Now when I turn on the AC, lights etc the engine never pulls down with the extra load. Gonna take the ferry to Lombok in a few days which is a 4 hr journey from Bali. Cruise around that island for a month before taking the ferry back west to Bali, then 4 hr drive to gillamanook then ferry again to Java 1 hour where the pretty girls live.

Guessing the 120 amp alternator has a build in voltage regulator. That explains the need to bypass the one on the firewall.