165 Amp Alternator

[jrou111]

I picked up a 165a Alternator from the local u-pull-it for $12

It came from an old ambulance with an IDI. There are two huge lugs on it, but no other plugs that I saw, at least not like how it looks in the FAQ on the 130a writeup.

It's got the same bracket and twin v-belt pulley as mine, so it looks like it'll bolt in. I'm just wondering how I'm supposed to wire it?

 

[riotwarrior]

go and look at the wiring on the one you took it off of....then duplicate or purchase that wiring.

 

[jrou111]

The vehicle I took it off of is long gone. It's okay, because I did some research and found that it's internally regulated and internally excited.

So all I have to do is run 4ga from the + to the isolator, and 4 ga from the - to ground.

What about the plug that I have? Should I just leave it disconnected? Guess I need to trace them back.

 

[Mr_Roboto]

The biggest factory alternators were 130 amps. What you have is probably either a Leece-Neville or a Delco. It should have at least one more connection on it, and may have had an external voltage regulator.

In my experience the high output alternators have very low output at idle and low speeds and you may get more useable power out of a factory 130a 3G. The ambulances have idle-up solenoids to get the engine speed up to where the alternator actually makes power.

 

[Al_E]

Does your alt look like this? This is a 165amp leece off a 90E-350 ambulance. The small black wire is power with key in run. Your alt wouldnt have the diode going to the batt terminal. The small red wire is my tach signal.

 

[jrou111]

Al - mine looks just like that, but it has a regulator where those three screws are.

Mr. Roboto - It's a Leece-Neville. I HAVE this 165a, and I don't have a 130a 3G. I found a pdf about my specific model, and it still puts out considerably more power than my stocker. It only has 2 big lug connections for power and ground.

 

[Mr_Roboto]

Al - mine looks just like that, but it has a regulator where those three screws are.

Mr. Roboto - It's a Leece-Neville. I HAVE this 165a, and I don't have a 130a 3G. I found a pdf about my specific model, and it still puts out considerably more power than my stocker. It only has 2 big lug connections for power and ground.

You're not getting what I'm saying.

The ambulance I had with a 230a Leece-Neville did not start charging until probably 1100 RPM. That's the way they were designed.

What you are looking at is maximum output - Most people want a larger alternator to charge at low RPM's to run inverters, equipment etc. I can't imagine what you would use 165a for running down the highway...

 

[FordGuy100]

So how much does a 3G alternator run? I'm thinking I might have to upgrade when/if I upgrade the stereo, more running lights, ect...

 

[redneckaggie]

i wouldn't see why you would need a bigger alternater to run your system I have the stock alt and run a 1.5 farad capacitor, a 200 watt head unit, a 250 watt amp running 4 6 1/2" mids and a 1000 watt amp with two twelves hooked to it. I also have neons and a cb

 

[redneckaggie]

my friend has ran a flatbed with 24 lights(not led), a 2500 wat amp running 4 twelves, a 180 watt head unit plus all of the stock stuff off of a stock alternator

 

[FordGuy100]

my friend has ran a flatbed with 24 lights(not led), a 2500 wat amp running 4 twelves, a 180 watt head unit plus all of the stock stuff off of a stock alternator

Well thats pretty re-assuring. Its just during school on the short drives to lunch, I can tell that I drain my batteries when I go to start the second time. With only a 2-3 minute drive, it just isnt enough time for my alternator, so I'm thinking a more powerful alternator, such as the 3G would cure most of that.

 

[MIDNIGHT RIDER]

Well thats pretty re-assuring. Its just during school on the short drives to lunch, I can tell that I drain my batteries when I go to start the second time. With only a 2-3 minute drive, it just isnt enough time for my alternator, so I'm thinking a more powerful alternator, such as the 3G would cure most of that.

It sounds to me that you lack battery-power, more than alternator-power.


The next time you need batteries, put in a pair of Group-30/31s, instead of the called for Group-27Fs; although much larger, they fit nicely.

The Group-30 and Group-31 are exactly the same battery, with the difference being that the 30 has the posts located offset/closer-to-one-side, whereas the 31 has the posts centered on the top.

I prefer the 31s centered posts, but have used both with equal success.



One other thing you can try that will help a bunch is to hook up a locking throttle-cable, with the tail-end having a ball-chain, such that the foot-pedal can easily over-ride it.

I have never fully understood the wisdom of having a diesel engine idle so low to begin with, unless it has something to do with the functioning of an automatic transmission; everything about a diesel fares much better when idling around 1200-RPM, instead of the usual 5-700-RPM.

With the locking throttle-cable, you can kick the RPMs up quite a bit, giving your alternator a better chance of charging things up; with an added advantage being a much better functioning A/C.

 

[jrou111]

Yes, but I don't idle very long. I crank the truck up, let it warm up ~2-3 min at 1100rpms. Then I take off on my 5 min commute @ 2000 rpms in 5th. There are no lights or turns so I stay at a constant ~50mph Then I pull into my space and I let it sit idle for 30sec, and shut her down.

So every day I idle maybe 1 or to mins. I have a short drive and I need to charge the batteries back up as quickly as possible.