down in Texas "where its warm"
Builds 1990 LJ78 in Montana (2 Viewers)
- Thread starter AirheadNut
- Start date
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yep! Global Warming at its finest.... 
Maybe we need an ice age to warm things up again!
Maybe we need an ice age to warm things up again!
We made another texas -> montana run a couple weeks ago, and are now back north. Camped in New-mexico and Wyoming, and the truck is doing great. I feel like I am finally relaxing to the point I can actually enjoy myself finally after all the crap the engine-swap kicked up. The rebuild seems to have done its job, the new npr alternator is feeding so many amps.. The injection pump still flutters a bit at around 1100-1200 rpm, so I'm not sure I'd recommend "M&D distributors" for your ip/injector rebuild needs, but I need to check out some other 13bt's maybe this is just how they run.
I will be turning my attention to the fun stuff next, intercooler, suspension, and potentially a re-gear, but probably not for a while.
Night 1: clayton lake NM
Night 2: Dugway Campground WY
I will be turning my attention to the fun stuff next, intercooler, suspension, and potentially a re-gear, but probably not for a while.
Night 1: clayton lake NM
Night 2: Dugway Campground WY
Another two... 
or three? round-trips between Texas and Montana trucks been great, the new alternator has been working excellently. I have a new problem to ask about, but first some travel/camping pics...
This was Hicks-Park campground on the main boulder road outside livingston mt, we were doing some agate hunting in the boulder river.
some wheeling on the forest roads north of cooke-city montana..
And here's a short video of us up above the stillwater mine outside nye mt on our way to the west fork of the stillwater.
Looking back at the last several months, I'm realizing I need to do a better job of taking pics at our campsites. When I'm out in it, seems like I don't really think about my phone.
or three? round-trips between Texas and Montana trucks been great, the new alternator has been working excellently. I have a new problem to ask about, but first some travel/camping pics...
This was Hicks-Park campground on the main boulder road outside livingston mt, we were doing some agate hunting in the boulder river.
some wheeling on the forest roads north of cooke-city montana..
And here's a short video of us up above the stillwater mine outside nye mt on our way to the west fork of the stillwater.
Looking back at the last several months, I'm realizing I need to do a better job of taking pics at our campsites. When I'm out in it, seems like I don't really think about my phone.
So yesterday my 4wd was working fine. Today, when I started up the truck, the hublock light came on, but no 4wd light. I took it out and made a hard turn with it, to see if it would do the 4wd-skip thing and it isn't, so I'm pretty sure it's not just a bad indicator light. In the threads I've read though in the past, seems like hublock is what most guys have trouble with, but my hubs are locking fine, just no engagement from the 4wd button. Suggestions welcome.
I had thought this at one point, but it just ended up being the bulb in the cluster. I could hear the actuator working, and the click, so this made me think it was working fine and just the bulb.
At another time, it was stuck in 4wheel and I could not get it out when pressing the 4wd switch on the dash. Turns out that time it was the plug on the back of the switch had vibrated loose.
If neither of those is the culprit, then I would check your plugs/wires/vacuum hoses and the VSV on the firewall that controls the actuator. Best of luck, hopefully it is one of those simple things!
will they click with the key in acc/ig or does the motor need to be running?
- Thread starter
- #249
The VSV's will activate with the key in the IG position, though there may or may not be enough vacuum to actuate the transfer case diaphragm. I don't know how audible the VSV's are, I've never heard them actuate.
welp they click. does the whole vacuum system work off the pump on the rear of the alternator? I'm guessing yes.
- Thread starter
- #251
That's correct, yes.
helpful threads.
seeking vacuum transfer case info - https://forum.ih8mud.com/threads/seeking-vacuum-transfer-case-info.1312666/ nice diagrams electrical to vsv
LJ78 JDM 4WD Problem - https://forum.ih8mud.com/threads/lj78-jdm-4wd-problem.224293/ troubleshooting steps, labeled pics of the vsv's
I can't seem to find good pics of the lines going into the t-case. I think I'm looking for something like this, but those lines look a lot larger than the hoses coming off my vsv's...
seeking vacuum transfer case info - https://forum.ih8mud.com/threads/seeking-vacuum-transfer-case-info.1312666/ nice diagrams electrical to vsv
LJ78 JDM 4WD Problem - https://forum.ih8mud.com/threads/lj78-jdm-4wd-problem.224293/ troubleshooting steps, labeled pics of the vsv's
I can't seem to find good pics of the lines going into the t-case. I think I'm looking for something like this, but those lines look a lot larger than the hoses coming off my vsv's...
- Thread starter
- #253
I can grab some photos for you tomorrow if that would help. Those are the correct lines, I can’t remember if the hoses step up in size from the VSV.
I found 'em
The hoses off the vsv's go into hard-lines toward the bottom of the firewall very similar to what the fuel lines do, then they break back out into larger hoses before entering the tc.. I tested both the 2wd and 4wd lines at the vsv and everything had suction when it should have suction. I swapped the lines as suggested in some other posts and still no 4wd light.
I also tried disconnecting each line one at a time from the TC and feeling for suction, and also leaving one line connected and checking the far end to test for a broken diaphragm both ways and again everything seems fine to me. I don't have a way to measure the force of the suction, but I would think, if the system was under-powered I'd also be having break trouble, which I am not.
It's snowing up here so I couldn't really get a good angle on the wiring harness coming down into the tc going to the three switches on the TC, but I did find some dangling wires, which, I'm PRETTY SURE? should be going to one of those three switches. It looks possible the wiring might have gotten drawn into the front-driveshaft and ripped apart.
So I think that might be my problem, but I'm gonna have to get someplace warm and well lit for a better look. If that is my problem, and these wires should be connected to the 4wd indicator switch on the tc, then the 4wd itself should be operational correct? It'd just be an indicator problem in that case?
The hoses off the vsv's go into hard-lines toward the bottom of the firewall very similar to what the fuel lines do, then they break back out into larger hoses before entering the tc.. I tested both the 2wd and 4wd lines at the vsv and everything had suction when it should have suction. I swapped the lines as suggested in some other posts and still no 4wd light.
I also tried disconnecting each line one at a time from the TC and feeling for suction, and also leaving one line connected and checking the far end to test for a broken diaphragm both ways and again everything seems fine to me. I don't have a way to measure the force of the suction, but I would think, if the system was under-powered I'd also be having break trouble, which I am not.
It's snowing up here so I couldn't really get a good angle on the wiring harness coming down into the tc going to the three switches on the TC, but I did find some dangling wires, which, I'm PRETTY SURE? should be going to one of those three switches. It looks possible the wiring might have gotten drawn into the front-driveshaft and ripped apart.
So I think that might be my problem, but I'm gonna have to get someplace warm and well lit for a better look. If that is my problem, and these wires should be connected to the 4wd indicator switch on the tc, then the 4wd itself should be operational correct? It'd just be an indicator problem in that case?
- Thread starter
- #255
That could very easily be your problem. If that's the case then yes, the 4WD will work fine but the indicator light in the dash will not. That switch on the transfer case basically grounds the indicator light circuit.
so what I'm hearing is, if I rub those two wires together, and they are what I think they are, my light will turn on.
- Thread starter
- #257
Yes, as long as your hubs are locked and those are the wires going into the harness and not coming out of the switch. Here is the applicable diagram:
the plot thickens still inches deep in snow up here but couldn't resist checking those wires. They do not appear to be the wires going to the 4h indicator switch, I put eyes on the switch today and it's still wired up. Not sure what those dangling wires are.
One of the other threads was talking about the 4L bypass, so I tried to throw it in 4L and to my surprise the stick felt loose, as if the other end wasn't connected to anything and it won't remain in position when I pull it all the way into low. Then I tried to shift out of neutral and found I was unable to. When I put the truck in park it makes a gears-grinding noise, and won't engage in any gear now. heh.
One of the other threads was talking about the 4L bypass, so I tried to throw it in 4L and to my surprise the stick felt loose, as if the other end wasn't connected to anything and it won't remain in position when I pull it all the way into low. Then I tried to shift out of neutral and found I was unable to. When I put the truck in park it makes a gears-grinding noise, and won't engage in any gear now. heh.
- Thread starter
- #259
Sounds like you may have lost the pin that connects the transfer lever with its pushrod, or perhaps the bolt connecting the pushrod to the transfer case has come loose. Would also be worth checking the bushings on the transfer lever pivot on the side of the transmission.
Yep pin gone. Threw a new one in there. That seems... coincidental. I think the two dangling wires might be from my ect button from the original tranny
