Need help diagnosing an issue with my Toyota 3B diesel — appreciate any input! (1 Viewer)

[Ginger ale]

Not long ago, I became the proud owner of my first Land Cruiser — and at the same time, my first diesel vehicle.
After the purchase, I immediately set off on a trip and drove it for 1,600 km. Every 400 km (at each fuel stop), I checked the oil level — and it never changed. The engine doesn’t burn oil: the level stayed consistent the entire time.
Fuel consumption during the trip home averaged around 12–13 liters per 100 km, which I think is ok for 3B.

But to fully understand the situation, I need to share a bit of the vehicle’s background.
This Land Cruiser was originally purchased new in Toronto in 1985 and stayed with its first owner until 1991. During that time, it clocked 122,000 km. Then it was sold to a second owner, who drove it only 22,000 km over the next 26 years, using it exclusively during the summer months.
In 2017, he gave the Land Cruiser to his neighbor, who also worked for him. According to the last owner, he wasn’t really a fan of the model — he simply kept the car as a sentimental gift, taking it out for a short drive once a year.
Finally, in May 2025, the vehicle came into my hands. The last owner mentioned that ever since he got it, the engine had trouble starting cold and would blow out a cloud of smoke — a mix of gray, white, bluish, and black — right at startup. However, it never consumed oil.
After the purchase, I drove it home without any issues — another 1,600 km — and once again, there was no oil loss.
After a bit of rest, I started working on the interior, fixing a few annoying little things. Now that all those are sorted, I’m ready to tackle the cold start issue.

I’d really appreciate hearing the community’s thoughts — feel free to share your opinions and say exactly what you think. Where would you start the diagnosis? Which steps make the most sense, and in what order would you approach the issue?
Thanks so much for your time and attention!


Video Overview:


In this video, I want to highlight a few issues and observations about the operation of my Land Cruiser (1985, diesel) that I have some questions about.

1. Clock and interior lighting dimming:
When I turn on the parking lights or low beams, the clock backlight slightly dims. The brightness adjustment knob doesn’t affect this at all.
Is this normal behavior, or should I be looking for an issue in the electrical system?

2. Engine behavior after a cold start:
The video shows the engine shortly after a cold start. After running for 4–5 minutes, a grayish-white-blue smoke appears with light throttle.
When revving harder, the smoke turns gray-black.
What could be causing this?

3. Injection pump:
I also show which type of injection pump is installed — maybe that will help with the diagnosis.

4. (Coming in the next video) Cold start:
Unfortunately, I forgot to record the actual cold start, but I’ll definitely film it tomorrow and upload it separately. The smoke is even more noticeable during that moment.

5. Engine shutdown:
In the second clip, you can hear how the engine shuts off — not smoothly, but with a few jerks or thumps.
It feels like one of the cylinders was about to fire, but the combustion was suddenly cut off.

Additional note:
The final video was recorded during my trip home. At that point, the engine was fully warmed up and wasn’t producing any smoke — neither at idle nor under throttle.


Video 1


Video 2


Video 3
Video 3 - https://youtube.com/shorts/0UBzn9dP_zs

 

[CRZR45]

Clock dims when headlight are on as to not be too bright at night in a dark cab.

 

[Ginger ale]

Clock dims when headlight are on as to not be too bright at night in a dark cab.

Good, so its normal. Thanks for your respond

 

[Behemoth60]

Ah... vintage 3B's. This is the extremely narrow topic on which I am a world leading expert. I've been wrenching on these engines since the 90's. Owned several, rebuilt a few. driven many 100's of thouhsands of kms on as far back as 1987.

In short, your engine is fine. Drive it and enjoy.

the long story... all 3B's smoke when cold. It's unburnt fuel from the cold engine. If it still smokes once it gets up to operating temperature... well, that's is also normal, but the 'white/grey' smoke should go away once up to temp. These machines are going on 40 years old.. no computers compesenting for temp, O2 levels or nuthin. Squish fuel, burn, move on. Absolutley no nonsense. Even a nuclear EMP blast will not stop this engine from running. zero bull**** going on under that hood.

The start up and shut down are also totally normal. No concerns there. On shut down, it take s rotation or two for all the fuel to run out of the lines and stop running.

The 'missing' needle on the oil guage is also surprisingly common. I've got 2 trucks with the oil guage needle has committed suicide. Wierdly, it's only ever the oil presssure guage too. I've never bother to see if that can be fixed/replaced, I am sure it can. But I usually end up with an aftermarket guage of some sort.

You have the inline injection pump. That's the good one. It will outlast the truck. When you push that lever forward and the engine stumbled, that is the fuel control lever. The EDIC <Electric Diesel Injection Control - Sounds fancy, but trust me, it's not - its the electric motor connected to that arm with a little rod) turns on/off the engine my moving that arm forward/back. Forward cuts fuel off. Middle is run, and Full back is 'over-inject' for starting. There is also a little pressure piston that pushes on the arm... that is supposed to be the high altitide compensator, in theory, at higher altitude, it reduces the fuel a bit so there is less smoke. I am not convinced it actually does anything. But screwing it forward/backward is how you adjust the 'fuel'. Burning black at full throttle... screw it back a turn. Want to roll some coal... roll it forward some.

Fun factoid about that EDIC.. sometimes, when it gets wet, it goes whacky and starts doing what I call the funky chicken... the motor just starts spinning, and as it turns, it pushes the fuel control arm from off, to run, to over inject, then back again in about 1 second increments. Makes it kind of hard to drive. If that happes to you, just pop that connecting rod off. You won't be able to turn the truck off with the key... stall it in gear, or pop the hood and pull that arm forward to kill it, but at least is will get you home.

If that is a genuince Canadian original BJ70, then you got a real rare truck. I see from the guage it is a 12V, so that make is a 1985. (The 86-87's that came to Canada were 24V) In the 3 years Toyota Canada brought them in, they only sold ~650 of them. Take care of that thing. It should be in a museum. I have an '86... bought it from the original owner. I 'retired' it with 640,000kms on the odometer, the body was totally rusting away from 30+ years of daily driving in Canada. Drivetrain was still perfectly fine to power on. Zippo I called it. Why? well, it would catch fire from time to time.

Hit me up if you have any questions. Or maybe need a few parts, I may have a few kicking around.

 

[Ginger ale]

Ah... vintage 3B's. This is the extremely narrow topic on which I am a world leading expert. I've been wrenching on these engines since the 90's. Owned several, rebuilt a few. driven many 100's of thouhsands of kms on as far back as 1987.

In short, your engine is fine. Drive it and enjoy.

the long story... all 3B's smoke when cold. It's unburnt fuel from the cold engine. If it still smokes once it gets up to operating temperature... well, that's is also normal, but the 'white/grey' smoke should go away once up to temp. These machines are going on 40 years old.. no computers compesenting for temp, O2 levels or nuthin. Squish fuel, burn, move on. Absolutley no nonsense. Even a nuclear EMP blast will not stop this engine from running. zero bull**** going on under that hood.

The start up and shut down are also totally normal. No concerns there. On shut down, it take s rotation or two for all the fuel to run out of the lines and stop running.

The 'missing' needle on the oil guage is also surprisingly common. I've got 2 trucks with the oil guage needle has committed suicide. Wierdly, it's only ever the oil presssure guage too. I've never bother to see if that can be fixed/replaced, I am sure it can. But I usually end up with an aftermarket guage of some sort.

You have the inline injection pump. That's the good one. It will outlast the truck. When you push that lever forward and the engine stumbled, that is the fuel control lever. The EDIC <Electric Diesel Injection Control - Sounds fancy, but trust me, it's not - its the electric motor connected to that arm with a little rod) turns on/off the engine my moving that arm forward/back. Forward cuts fuel off. Middle is run, and Full back is 'over-inject' for starting. There is also a little pressure piston that pushes on the arm... that is supposed to be the high altitide compensator, in theory, at higher altitude, it reduces the fuel a bit so there is less smoke. I am not convinced it actually does anything. But screwing it forward/backward is how you adjust the 'fuel'. Burning black at full throttle... screw it back a turn. Want to roll some coal... roll it forward some.

Fun factoid about that EDIC.. sometimes, when it gets wet, it goes whacky and starts doing what I call the funky chicken... the motor just starts spinning, and as it turns, it pushes the fuel control arm from off, to run, to over inject, then back again in about 1 second increments. Makes it kind of hard to drive. If that happes to you, just pop that connecting rod off. You won't be able to turn the truck off with the key... stall it in gear, or pop the hood and pull that arm forward to kill it, but at least is will get you home.

If that is a genuince Canadian original BJ70, then you got a real rare truck. I see from the guage it is a 12V, so that make is a 1985. (The 86-87's that came to Canada were 24V) In the 3 years Toyota Canada brought them in, they only sold ~650 of them. Take care of that thing. It should be in a museum. I have an '86... bought it from the original owner. I 'retired' it with 640,000kms on the odometer, the body was totally rusting away from 30+ years of daily driving in Canada. Drivetrain was still perfectly fine to power on. Zippo I called it. Why? well, it would catch fire from time to time.

Hit me up if you have any questions. Or maybe need a few parts, I may have a few kicking around.

Thank you very much for your reply!
About 15 minutes ago, I performed a cold start. At first, the engine was misfiring slightly — I kept cranking the starter until I felt the engine had fully caught and wouldn’t stall.
There was quite a lot of smoke during the start. The misfiring lasted for about 30–40 seconds, then the engine started running smoothly, but the smoke remained.
This kind of cold start behavior happens every time.
What would you recommend checking first?

Video 4 (Cold Start)

 

[Behemoth60]

There was quite a lot of smoke during the start. The misfiring lasted for about 30–40 seconds, then the engine started running smoothly, but the smoke remained.
This kind of cold start behavior happens every time.
What would you recommend checking first?

What was temp outside when starting? On a warm summer day it probably should start slightly better than that... but not a lot. This is life with an old diesel... they are hard to start, smoke on cold starts, and make the neighbours nervous. This is just what it is. This will never start as simple, smooth and clean as a modern vehicle. ever.

A few things to check... make sure your glow plug system is healthy:
1. check glow Relays... there is a big glow relay on the port side fender... it should click on/off when the glow plug lights are on.
2. Test for voltate at the glow plugs immediately after turning the key. Should start at 12ish volts briefly, then drop to about 8, then to zero when they time out. Time of glow is based on engine temp... there is a dedicated temp sensor in the thermostat housing just for timing the glow plug cycle. There is a chart in the FSM how long each stage should run based on ambient temp.
3. No voltage? Check fusable links. I think the glow plugs 'fuse' through fusable link at the 12V battery terminal.
4. Test each glow plug... there should be a certain amount of resistance through them. Too much/little, it is burnt out and needs to be replaced. replace them all if one is bad.

BUT>>>>>>

overall... seriously, this is kind of just how they work. Some start better than that, but it does start after just a few cranks <- that's a win. The direct injected variants (like the 12Ht and the 13BT) are excellent at starting, and they spring to life, but the indirect injected diesels like the 3B... this is just how they work. it will never not smoke on a cold start. Remember, modern diesels are 5 generations newer than this. The 3B represents really the most basic of 2nd generation of commercially produced diesels. That engine was engineered in the 1970's. Smoking was very popular back then, even for engines. I would run those tests I suggested, and if they pass, then you got nothing to worry about. Just enjoy that vintage technology.

 

[Behemoth60]

 

[Behemoth60]

 

[Behemoth60]

 

[Behemoth60]

 

[CRZR45]

I had similar cold start on my 3b in my bj73. I did the “Wilson Switch” basically a momentary button on the dash directly wired to glow plugs. I glow it 10 seconds then release and another 10 seconds and it fires right up no smoke as it did when my glow system failed. As stated above the 13bt I have starts after barely 1 revolution of the motor. Not rockets but fun easy to work on simple workhorse reliable motors. Nice BJ70!!

 

[bj70bc]

Hey there.
I own a '86 canadian 3b bj70.... had two of em.... sooo
1) You need to turn the thumb throttle up about 2.5 full turns and glow it to start flawlessly, mines on a momentary 'wilson' switch so i choose glow duration.
Summer, winter, whatever itll start the same if you do this
2) almost certainly you have a very minor amount of air getting into your fuel system after you shut it off from contraction of the hot fuel pulling air into the system, chances are it is coming from the fuel primer on the injection pump, you should replace this with a bosch unit, like 50 bucks just screws on... just do it. There may be other air intrusions, address this after replacing the primer pump.
3 Your glows are probably having a minor issue, old glows or the glow controller is at the end. My 'Best' solution is a wilson switch, some want original functionality but i am of the school that the driver choosing glow duration for the starting situation is the best solution as start conditions vary and you can continue glow or feather the glow after starting to smooth it out. Look up wilson switch in google under 'wilson switch bj70, ih8mud forum'

do all of these things and she will start with no smoke whatsoever and with very little starter input ( mine is almost zero smoke on startup)

 

[Ginger ale]

What was temp outside when starting? On a warm summer day it probably should start slightly better than that... but not a lot. This is life with an old diesel... they are hard to start, smoke on cold starts, and make the neighbours nervous. This is just what it is. This will never start as simple, smooth and clean as a modern vehicle. ever.

A few things to check... make sure your glow plug system is healthy:
1. check glow Relays... there is a big glow relay on the port side fender... it should click on/off when the glow plug lights are on.
2. Test for voltate at the glow plugs immediately after turning the key. Should start at 12ish volts briefly, then drop to about 8, then to zero when they time out. Time of glow is based on engine temp... there is a dedicated temp sensor in the thermostat housing just for timing the glow plug cycle. There is a chart in the FSM how long each stage should run based on ambient temp.
3. No voltage? Check fusable links. I think the glow plugs 'fuse' through fusable link at the 12V battery terminal.
4. Test each glow plug... there should be a certain amount of resistance through them. Too much/little, it is burnt out and needs to be replaced. replace them all if one is bad.

BUT>>>>>>

overall... seriously, this is kind of just how they work. Some start better than that, but it does start after just a few cranks <- that's a win. The direct injected variants (like the 12Ht and the 13BT) are excellent at starting, and they spring to life, but the indirect injected diesels like the 3B... this is just how they work. it will never not smoke on a cold start. Remember, modern diesels are 5 generations newer than this. The 3B represents really the most basic of 2nd generation of commercially produced diesels. That engine was engineered in the 1970's. Smoking was very popular back then, even for engines. I would run those tests I suggested, and if they pass, then you got nothing to worry about. Just enjoy that vintage technology.

Thanks for the tip!
I have those PDF manuals — @Felde sent them to me. I'm actually going through them right now, really interesting stuff.
I'll definitely start by checking the glow plug system — seems like the most logical first step.

 

[Ginger ale]

I had similar cold start on my 3b in my bj73. I did the “Wilson Switch” basically a momentary button on the dash directly wired to glow plugs. I glow it 10 seconds then release and another 10 seconds and it fires right up no smoke as it did when my glow system failed. As stated above the 13bt I have starts after barely 1 revolution of the motor. Not rockets but fun easy to work on simple workhorse reliable motors. Nice BJ70!!

The truck is still pretty new to me, and I haven’t figured everything out yet.
It looks like I have a switch similar to the Wilson one installed, but I’m not sure if that’s actually what it is.
When I bought the truck, the previous owner told me to just hold the switch for 5–10 seconds before starting — so that’s what I’ve been doing, but I had no idea what it was for.
I’ll record a video tomorrow — maybe you guys can help me identify it.

 

[Ginger ale]

Hey there.
I own a '86 canadian 3b bj70.... had two of em.... sooo
1) You need to turn the thumb throttle up about 2.5 full turns and glow it to start flawlessly, mines on a momentary 'wilson' switch so i choose glow duration.
Summer, winter, whatever itll start the same if you do this
2) almost certainly you have a very minor amount of air getting into your fuel system after you shut it off from contraction of the hot fuel pulling air into the system, chances are it is coming from the fuel primer on the injection pump, you should replace this with a bosch unit, like 50 bucks just screws on... just do it. There may be other air intrusions, address this after replacing the primer pump.
3 Your glows are probably having a minor issue, old glows or the glow controller is at the end. My 'Best' solution is a wilson switch, some want original functionality but i am of the school that the driver choosing glow duration for the starting situation is the best solution as start conditions vary and you can continue glow or feather the glow after starting to smooth it out. Look up wilson switch in google under 'wilson switch bj70, ih8mud forum'

do all of these things and she will start with no smoke whatsoever and with very little starter input ( mine is almost zero smoke on startup)

For example, if it’s around +10 °C outside, would it really start that poorly without the glow plugs, or should it still start reasonably well?

 

[OGBeno]

For example, if it’s around +10 °C outside, would it really start that poorly without the glow plugs, or should it still start reasonably well?

It should start no problem. Without glow.

 

[Squash]

Typical 3b.
Good glow plugs lessen the smoke and allow colder starts.
Your IP has a leather diaphragm which eventually needs some luv'n. Use 100% Neatsfoot oil to keep the leather supple.
I picked up a Toronto 1985 bj70 in 2019 and drove her to Alaska, Dawson, Arctic Circle. Drove solo while flying my son to Anchorage so we could backcountry ski. Minor issue of losing the alternator at the ArcticCircle. I unplugged the EDIC, and drove her like an old farm tractor. Stall out on a hill, and pop the clutch in the morning to start.

 

[CRZR45]

The truck is still pretty new to me, and I haven’t figured everything out yet.
It looks like I have a switch similar to the Wilson one installed, but I’m not sure if that’s actually what it is.
When I bought the truck, the previous owner told me to just hold the switch for 5–10 seconds before starting — so that’s what I’ve been doing, but I had no idea what it was for.
I’ll record a video tomorrow — maybe you guys can help me identify it.

Pull your glow plugs and replace them. Sounds like you already have the Wilson switch. I always base line consumables like that when I get a new truck .

 

[Felde]

Hi
Your first vids on running the engine: All total normal and fine.
Ful consumption: Absolutely normal. Mine also uses 12l/100km. Always.
Blowby: Actually good!
I second @Behemoth60 on all his comments on this.

Cold start: Not that normal. Mine (same config, except 24V) starts much better. But it's not the cranking. I see it starving for fuel..
In general:
- Make good use of the 'choke' screw (actually it's a manual accelerator).
- Make sure your glow plugs are good. (They are wearing items and need replacement after a while, probably never done on your truck. While those are out, it's the perfect time to do a compression test, too).
I can't recommend the 'Wilson switch' in your case: The glow system is quite Ok, when all parts are in good working order. What I can see from the instrument lights at startup: No indication that your glowing relais might be faulty. Start with the easy and probable thing: Replace glow plugs.

I'm with @bj70bc. I made the same note in my comment on your introduction post: Probably a very tiny air leak that makes the fuel run back when parked and causes air in the line on startup.
Those things are generally hard to diagnose. Recommend to check the condition of your fuel lines (i.p. the rubber sections) and your fuel pickup pipe on the tank (the bend on the top is notorious to rust). I briefly also saw the priming pump on the IP. Is it wet? (Maybe I'm mistaken). Anyways it appears to be old. The priming pump also is notorious to leak and let air in at old age.
Next time the truck had been sitting for 1-2 days: Try to actuate the priming pump before starting the engine. You shouldn't be able to move it much. If you can move it, there's air in.
Altogether: Very nice find. Just needs some TLC (as to be expected as per its recent history). Enjoy it !
Cheers Ralf

 

[fjc-man]

How about some basics, check and ajust the valve clearances. I know it’s a little more involved on a diesel but a compression test might not be a bad idea.