How long will a HDJ80 run without an alternator? (1 Viewer)

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I swear I must not be doing a good search because I am sure this is a constant question but I cannot find anything good. Has anyone done a draw down on a stock diesel 80 that could tell me what I am pulling? I am waiting for an alternator pulley and thought it still might be driveable with two group 31's and a deep cycle AGM. I figured this would be every tenth question. I know I am running the fuel pump and solenoid. And any screaming lights on my dash. Brake lights. What else is running? I can pull the radio fuse. I could even roll start it since it is manual.
 
Truck will stay running for hours and hours with that much battery on board. No electric fuel pump to run, lift pump (which draws fuel from tank) is built into injection pump. Diesel life for the win.

I once drove my LN106 hilux with two batteries around 600 rainy miles with no charging system. That included occasional use of wipers, radio, and by the time it got dark headlights also. Wasn't awesome, lights were very dim by the time I got to where I was going but truck didn't shut off until I hit the key to do so.

This being said, I suspect it would be possible to daily the truck just fine, get to work or whatevever needs doing within reason. Throw a charger on it at night.

What happened to your original alt pulley? If your concern is about swapping it over, I didn't require a puller or any such thing when chaning the alternator in my '92 jdm HDj81. Also interesting, there are a variety of stock Toyotas that use a very similar if not identical alternator, certain years of Tercel come to mind, quite a few others also I believe. Lots of info about that here on mud.
 
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Great info thanks. Didn't know that about the pump but even better. I had it in my head because of my old gas F80. As for the alternator, I mangled my pulley trying to remove it from my original alternator. It was total impatience on my part. The bolt just would not free up and just spun. I tried to put positive pressure on the pulley and it snapped. I definitely was not being careful enough. I bought a new Tercel high output 130 amp alternator and the pulley that came with it wasn't going to work. Only place I could find one was UAE. But now I am looking forward to driving around and trying this out.
 
Very little electrical draw on a mechanical diesel, especially if you don’t have daytime running lights. I had a voltage regulator fail on an LN106 and the DRL’s drained the battery pretty quickly. I pulled the fuse on the headlights and after an hour stopped at an auto parts store to get the battery checked, it was at 3.4v. I drove for another 200mi until it started to get dark.
 
You do need to spin the water pump.
In an emergency an old timing belt will work, just can't drive to fast.
Now if someone was to make a manual override of the fuel solenoid you could drive forever!
 
You do need to spin the water pump.
In an emergency an old timing belt will work, just can't drive to fast.
Now if someone was to make a manual override of the fuel solenoid you could drive forever!
the manual override is pretty simple - just remove the plunger / pin from the fuel cutoff solenoid and you're good to go forever

but, in this case without the alternator v belt there is nothing to drive the waterbody
 
But the solenoid would work with batteries though right?
 
Yes it will work.
 
Hey buddy, maybe I can help? If the alternator pulley is still manufactured and in the Toyota system I can ship you one. Tell me what you need on a PM.
 
I got about ~700 miles out of my HDJ81 with a failing alternator… this was all highway driving.

Regulator failed, but mine was overcharging. Might be different in your case. Replaced the batteries a few months later for good measure.
 
2 days in the bush
 
Great info thanks. Didn't know that about the pump but even better. I had it in my head because of my old gas F80. As for the alternator, I mangled my pulley trying to remove it from my original alternator. It was total impatience on my part. The bolt just would not free up and just spun. I tried to put positive pressure on the pulley and it snapped. I definitely was not being careful enough. I bought a new Tercel high output 130 amp alternator and the pulley that came with it wasn't going to work. Only place I could find one was UAE. But now I am looking forward to driving around and trying this out.
 
I was told today you need an impact wrench to get the bolt undone I'm in the UK a company called unipart in London are being very helpful.
 
In a pinch the timing belt will run the water pump.
Fish a timing belt over the fan onto the water pump pulley and over the crank pulley. Now you can't drive very fast, 60kph seems the limit because the fan creates resistance which causes slippage, which creates heat. But damn does it get you out of a jackpot.
 

I was told today you need an impact wrench to get the bolt undone
No doubt it makes it easier, but I have gotten 2 off without one.
 

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