Builds 1992 LJ78 build/refresh (2 Viewers)

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I was thinking about something Nick. I bet you are spot on that my issue is fuel related.
If the truck sits overnight, it starts hard and smoky. If I kill it and restart within a few minutes, it fires immediately. If I let it sit for a couple of hours but the engine is still warm it takes it a second longer to catch. No smoke and roughness, but a bit slower to catch.
It makes sense if I have a small amount of air getting in through a hose or the primer pump. It get's progressively worse the longer the truck sits because more air is allowed into the system. It's never enough to make it not crank and really is only blatantly obvious on a cold start.
I drove the truck a lot today and shut if off for various amounts of time throughout the day. Starting speed is related to how long it was shut down ,I think, now that I was really paying attention to each start to see how it behaved.

I agree that it's a very high chance it's fuel related. The big clue for me was that glowing longer made no difference, however I think you observations about it getting worse when sitting longer are likely correct. As the vane pump in the front of the injection pump draws in fuel when the engine is running, it's also sucking air in where ever the leak is (probably primer pump). When the truck sits, that air which is probably mixed in pretty good in the fuel will rise and turn into larger bubbles (in injection lines). This will cause the worst issues on start up.
 
Well, we were both wrong. You had me convinced. Not that it was hard. The symptoms pointed that way.
2 of the new glow plugs I had installed were bad. Which is also why the second cycle made no difference. I still had 2 cold cylinders. So, those 2 were stumbling and dumping unburned fuel on initial start.
I pulled them all to test on the bench and found 2 had high OHM values. I guess those plugs are just crap. They have about a 1500 miles on them and have been getting progressively worse. I went through the Superglow system again to make sure it wasn't staying on and burning them. It all seems to be functioning correctly. Which was my finding when I first started checking it, but thought I would check again.
I will probably order a set of the Bosch ones and keep as spares.
I had a second set of the ones I was running. They are working perfectly for now. So, at least I am getting clean starts with no smoke again.

I did go through and replace all the spring clamps on the fuel system yesterday. It's not like it was a waste. Those old spring clamps weren't as tight as I like and were starting to corrode. And, ordered the cheaper fuel primer from Australia. I really want that to be working anyway.

I also ordered extended brake lines. I have left my anti sway bars in place to keep from stretching my existing lines, but they seriously limit flexibility in the stock location.
 
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Well, we were both wrong. You had me convinced. Not that it was hard. The symptoms pointed that way.
2 of the new glow plugs I had installed were bad. Which is also why the second cycle made no difference. I still had 2 cold cylinders. So, those 2 were stumbling and dumping unburned fuel on initial start.
I pulled them all to test on the bench and found 2 had high OHM values. I guess those plugs are just crap. They have about a 1500 miles on them and have been getting progressively worse. I went through the Superglow system again to make sure it wasn't staying on and burning them. It all seems to be functioning correctly. Which was my finding when I first started checking it, but thought I would check again.
I will probably order a set of the Bosch ones and keep as spares.
I had a second set of the ones I was running. They are working perfectly for now. So, at least I am getting clean starts with no smoke again.

I did go through and replace all the spring clamps on the fuel system yesterday. It's not like it was a waste. Those old spring clamps weren't as tight as I like and were starting to corrode. And, ordered the cheaper fuel primer from Australia. I really want that to be working anyway.

I also ordered extended brake lines. I have left my anti sway bars in place to keep from stretching my existing lines, but they seriously limit flexibility in the stock location.

Nice work!! Glad it turned out to be pretty simple. The Bosch plugs will be a good investment. When my old short block was at it's worst I had to triple glow to get a clean start. The plugs took it and are still going strong after years of use! The new primer and hose clamps are definitely a good investment too! An ounce of prevention is worth a pound of cure as they say....
 
Not much new to report.
I put my longer brake lines on and removed the sway bars. That made the truck a tremendous amount more flexible. I can get out to about 26" height on my retaining wall before it lifts a tire. Close to the same forward and backwards. The truck was like a rigid board with the sway bars in. I am happy enough with that for my purposes. I have had much more flexible trucks, but I no longer have the need to drive over every boulder I see now. I am lazy, I just go around.
I am contemplating a rear bumper build, but haven't really decided what I want to do yet.
I have a stack of 3/8"/10MM aluminum plate. I have considered building a bumper out of that. But, I want to do a swing away tire carrier and haven't quite worked out how to do the pivot yet in an aluminum bumper. I know it's possible, but I am concerned about my abilities to get it so that it doesn't stretch the aluminum and get loose, but also not be some ghetto setup to build it up enough to take the stress.

Aftermarket extended brake lines for the LJ78 are :
Bendix 78575
or
Dorman H380535
or
Raybestos BH380535
or
Wagner BH138042

I know the Dorman are available on Amazon

This is cross reference for Toyota 96940-34705 brake line



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Not much new to report.
I put my longer brake lines on and removed the sway bars. That made the truck a tremendous amount more flexible. I can get out to about 26" height on my retaining wall before it lifts a tire. Close to the same forward and backwards. The truck was like a rigid board with the sway bars in. I am happy enough with that for my purposes. I have had much more flexible trucks, but I no longer have the need to drive over every boulder I see now. I am lazy, I just go around.
I am contemplating a rear bumper build, but haven't really decided what I want to do yet.
I have a stack of 3/8"/10MM aluminum plate. I have considered building a bumper out of that. But, I want to do a swing away tire carrier and haven't quite worked out how to do the pivot yet in an aluminum bumper. I know it's possible, but I am concerned about my abilities to get it so that it doesn't stretch the aluminum and get loose, but also not be some ghetto setup to build it up enough to take the stress.

Aftermarket extended brake lines for the LJ78 are :
Bendix 78575
or
Dorman H380535
or
Raybestos BH380535
or
Wagner BH138042

I know the Dorman are available on Amazon

This is cross reference for Toyota 96940-34705 brake line



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View attachment 1847571

View attachment 1847575

How does it perform on road without the sway bars? I’ve been contemplating taking mine out to gain some flex, but am not sure given that it will be my daily and see a lot of highway travel.
 
Honestly, can't really tell the difference.
The Land Cruiser is a way stiffer truck than any of my Land Rovers, and I have ran every one of those I have ever had without. Some I daily drove.
I have had a few really built trucks I would not have enjoyed daily driving, but I think the Prado would be fine.
Actually my biggest complaint with the Toyotas I have driven is the slightly vague steering. Every one I have driven in both stock and modified form had vague steering in my opinion. Body roll is pretty minimal however it seems.
 
Haha, that brick wall is perfect for testing your flex! Truck looks excellent! Thanks for the flex pictures.

I've often run without front and rear sway bar. I just drive a bit slower to compensate. I think the only time I'd be concerned is if I had to do a quick evasive maneuver to avoid an accident. Having sway bars on might make the difference in this case.

When I tow my camper trailer I run with both sway bars on for better stability.

Currently, I've been running only a rear sway bar. I've found the rear seems to always flex better than the front, so I'm trying to even it up a bit to force the front to flex better. Also, I've found it much more comfortable to drive this way. The front sway bar seemed to really pull the truck down into every uneven dip in the road.

Thanks very much for those brake line part numbers! This is something I've been meaning to do for years now.
 
Also, I've found it much more comfortable to drive this way. The front sway bar seemed to really pull the truck down into every uneven dip in the road.

Oh, that's interesting. My wheels tend to want to follow every groove and frost heave in the road. That, coupled with the vague steering, tends to make driving very interesting at times. I hadn't considered that the problem might be caused by the front sway bar. Thanks.
 
Oh, that's interesting. My wheels tend to want to follow every groove and frost heave in the road. That, coupled with the vague steering, tends to make driving very interesting at times. I hadn't considered that the problem might be caused by the front sway bar. Thanks.

The problem you are describing might be a bit different. When I replaced my knuckle bearings (king pin bearings) they were worn oval, and made the truck really just want to go straight and follow ruts (how you are describing). The other thing that can cause this is a lift if you have not done castor correction. Might want to look at ball joints too...

What I was trying to describe is the front sway bar was so tight it would pull the whole truck into a hole rather than just let the axle tilt down into the hole while I was driving. It gives a tippy feeling at the truck rocks side to side into dips. That said, I had given my truck a lift, but not put in sway bar extensions, so my sway bar was probably tighter than normal.
 
The problem you are describing might be a bit different. When I replaced my knuckle bearings (king pin bearings) they were worn oval, and made the truck really just want to go straight and follow ruts (how you are describing). The other thing that can cause this is a lift if you have not done castor correction. Might want to look at ball joints too...

The problem isn't as bad as it used to be. I've got about a 2" OME lift, but haven't done anything about caster. I've rebuilt my right-side steering knuckle, but didn't notice any unusual wear in the bearings. Getting set to do the left side and I'll be sure to check. I've replaced all of the tie rod ends. It tracks truer than it used to, but I still need to pay close attention when there's any degree of uneven pavement.
 
The problem isn't as bad as it used to be. I've got about a 2" OME lift, but haven't done anything about caster. I've rebuilt my right-side steering knuckle, but didn't notice any unusual wear in the bearings. Getting set to do the left side and I'll be sure to check. I've replaced all of the tie rod ends. It tracks truer than it used to, but I still need to pay close attention when there's any degree of uneven pavement.

It's probably the caster. I drove for quite a while with a lift and no castor correction, and it took quite a bit of concentration to keep the truck on the road. I put in offset bushings, but wish I'd done something different, as the offset bushings limit articulation as well. The bushings did make all the difference to the steering though.
 
It's probably the caster. I drove for quite a while with a lift and no castor correction, and it took quite a bit of concentration to keep the truck on the road. I put in offset bushings, but wish I'd done something different, as the offset bushings limit articulation as well. The bushings did make all the difference to the steering though.

Well okay then. I'll put that on the (large and growing) list of things to do. Thanks Nick.
 
Well okay then. I'll put that on the (large and growing) list of things to do. Thanks Nick.

I agree with the caster correction. With my 3" dobinsons lift I put in a caster correction (offset from them) and it helped the steering. I need to do my kingpin bearings and knuckles next as I still have a slight pull to the left and I think it's related to kingpin bearings being worn (there's nothing else to replace for me in my suspension and steering). I'm considering taking off my front swaybar now as well after reading this. I have added sway bar extenders after my lift on the front and back. For wheeling I definitely felt limited by my sway bars, but was reticent to remove them as it is also my daily driver. Thanks for the feedback guys, that's great.
 
So, I haven't posted anything on this thread in a while.
Back around May my head finally gave up the ghost and I had far too many projects to deal with over the summer to get into this.
Last Tuesday after work I pulled the Cruiser into the shop and tore it down to see what I might find.
I am cracked in 3 of the 4 cylinders. And, I suspect, it had been cracked as long as I have had the truck. The erosion in the head does not correspond to the amount I have ran the engine, so I suspect it had started to crack before I even had it in the country and all my mods to keep the truck cool had prolonged the head a little longer than if I had been running stock. I had lingering doubts about the head all along, but it hadn't catastrophically failed, so was being very hard to pinpoint with any degree of certainty.
When it finally went in the spring I suspect it was due to a faulty Tridon Tstat. It ran up to 220F right down the road from my house and it had never broken 200F prior to that, I caught it quickly as my Madman gauge has warnings set on it at 205F. However testing my tstat led me to discover it was barely opening. And, because I took my sender out of the filler neck and put it inline in the hose so I could keep my factory gauge operational, it likely got hotter than that before the Madman was able to sense the temps and light up a warning.

I have spent all summer going back and forth about which way I was going to go with repair. I was pretty much set on putting a 1UZFE in it. After talking with several members and various others about the swap, I knew I would be happy with the end result. I was just reluctant to get into a motor swap with some other projects I have ongoing. It's pretty easy and straightforward as far as motor swaps go, but I knew it would take me much longer to get it wrapped up to my satisfaction. So, this week me and @GTSSportCoupe have talked quite a lot about various options and ways to go with it and I have decided to repair it and get the truck back on the road. Besides waiting on parts and and and other things I will do while I am in there, it's basically 1 more day of work as opposed to weeks of fabbing and wiring to get the 1UZ dialed in and looking factory.

I am taking this opportunity while I wait for parts to run all the misc pieces through the blasting cabinet and repainting them so everything looks good when I reassemble. I am going to have my injectors rebuilt while they are out.
After taking everything apart and inspecting the cylinders, they are actually in outstanding condition. #4 does have corrosion in the top ,but fortunately its all above the ring lands, so I should have no compression issues. #4 always had slightly low compression, but after disassembly it's because the seat of the exhaust valve has some corrosion on it, so it was never sealing correctly. Fortunately I have never had any water make it past the rings, so no water in the bottom end like a lot of poeple find. I am actually surprised I have never found any moisture in the bottom end.

I haven't done anything yet except start repainting parts, but I will keep the pictures coming as I get parts in.

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