2L diesel swapped 1986 4Runner

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Is it still summer diesel in the tank? That definitely won't help. Does the glow system work? Cold starts will always be a bit tough, but much harder with a poor glow system. Also, it does take time for air to work it's way completely out of the fuel system. Air can cause weird stumble issues.

Heres a vid of mine at -8c with 10sec glow a few days ago. No block heater or anything used there. Running 10w30. It starts like that down to -15c. Below that I plug in block heater. Usually only if I'm in the interior. Island stays warmer.

Oh wow that starts right up. Okay yeah I will test all the plugs lol. I installed a brand new fuel tank a few weeks ago and filled it with pump diesel, I would assume they switched over to winter diesel here already. One thing to note, I'm still running the fuel filter from the summer that probably has some old biodiesel in it still. I've only run it for about 10 minutes total so it is possible its still burning oil fuel nd might have some air.

I might turn the fuel screw down a bit as it is very black coming out the tailpipe while its falling over itself trying to start. I'll have to take a look in the manual to see if it tells you how many turns out is factory.

Another thing, I don't know how well the video picks it up, but the diesel knock is quite loud, I notice a distinct knock that sounds different, I can't really pinpoint what it is though. The machine shop put in new wrist pins and checks all the tolerances so nothing should be making weird noises.

Merry Christmas! LJ is very clean, I'm a bit jealous haha.
 
Oh wow that starts right up. Okay yeah I will test all the plugs lol. I installed a brand new fuel tank a few weeks ago and filled it with pump diesel, I would assume they switched over to winter diesel here already. One thing to note, I'm still running the fuel filter from the summer that probably has some old biodiesel in it still. I've only run it for about 10 minutes total so it is possible its still burning oil fuel nd might have some air.

I might turn the fuel screw down a bit as it is very black coming out the tailpipe while its falling over itself trying to start. I'll have to take a look in the manual to see if it tells you how many turns out is factory.

Another thing, I don't know how well the video picks it up, but the diesel knock is quite loud, I notice a distinct knock that sounds different, I can't really pinpoint what it is though. The machine shop put in new wrist pins and checks all the tolerances so nothing should be making weird noises.

Merry Christmas! LJ is very clean, I'm a bit jealous haha.

Merry Christmas to you too. And thanks for the comments on the LJ. It does have some rocker rust you can't see....lol. But I do love the truck and it does run great.

Don't remove your glow plugs. Just disconnect the glow rail and test resistance of each one against the factory manual spec. Once you've confirmed they're good, then have someone glow the engine, and check that you're getting 11V or so to the rail for at least 7-8 seconds. I'm not sure if your motor has after glow or not, but if so, you'll see 6V or so after the main glow for quite a bit longer.

If your glow system isn't working, you could try manually glowing from battery to glow rail with some jumper cables for 10 sec before starting.

Definitely the old diesel in your filter could be causing challenges until it flushes back to the tanks. The rotary pumps use fuel to cool themselves and the injectors, so pull more fuel than they need and circulate back to the tank. So it will eventually get thru. If you have a spare filter, you could fill it with fresh diesel and install in place of the other one though.

I found it takes a couple days of driving to really work the air out. So definitely you're still going to have some in there for a while causing you starting grief and weird stumbles and noises.

If the truck was running ok with the fuel screw where it is before you rebuilt, then just leave it!! Other wise you're just adding more variables to the equation. Very little turn on those can make a big difference. I'd say don't touch it for now.

If you look at pump specs, they give full fuel below a certain rpm. The way your motor was stuttering away, it makes sense that the pump was putting out full fuel and you're getting black smoke. It was just trying to get up to idle rpm. I would not worry about that yet.

Loud diesel knock is to be expected when there is still air in the system. But also, I found new injectors are always louder. Means a faster cleaner fuel burn making more of a diesel 'knock'. It's a good sign as long as the engine is running fine. Too much advance makes a bad diesel knock also, but is accompanied by no power and tons of white smoke. That is obviously not a good thing.
 
Well today was.... eventful.
It still has a bad miss and blows white smoke, it feels 100% like a fuel starvation issue. You floor it and it just falls on its face.
Here is a video of how it was

I went ahead and put a brand new fuel filter in. When I drained the water separator, what came out was very rusty and brown. After filling the new filter and priming it, it ran the same. However, I turned it off and let it sit for a minute, then fired it up again, and it started like how it should! no miss at all, very minimal smoke out the tailpipe!

So I took it for a drive, it didn't have as much power as it should, it ran clean for about a minute, then started blowing white/blue smoke so I turned around. I noticed I was losing power and the pyro was going up to 600 degrees, then it died on me. Felt exactly how it felt back in the summer when I would clog fuel filters with rust and biodiesel...

I let it sit for a minute, then cranked for about 20 seconds with my foot to the floor. It fired up with some very thick black/white smoke. I tried driving back home again but only made it about 20 meters until I lost power again. This time I didn't have enough battery to crank it. So I walked back home and got my truck and tow strap.

Back home, I jump started it and it blew clean. I eased it nicely back into its parking spot but it was defiently down on power. Not too much white smoke this time. And thats where we sit now.

I've verified the fuel timing many times, even advanced the pump slighlty. Fuel filter and tank are brand new. Injectors are brand new from the shop (I assume they were pop tested). My only thought now is to replace the injector pump.
 
Drain your filter again into a clean container, see what comes out, let it settle carefully for a few minutes, watch for water. I realize tank is new, but what did you fill it with..? Guessing a jerry can probably filled from local station that may have nasty junk in their tanks, you never know.
 
Just drained got a sample from the filter. Diesel looks clean. There were some particulates mixed in so the lines could have some residue in them. I just noticed I had a hose clamp missing on a part of the fuel line. I put a new clamp on and the engine seems to run clean now. Idles smooth. I took it up the driveway a few times and it was fine. Went for a quick lap to my neighbors driveway and back and as I was coasting down my driveway it wanted to die again. No smoke but high pyro temps. I’m too tired to even try and figure this one out. Tomorrow I’ll see if the fuel hoods prime still.
 
I just tried firing it back up and it definetly lost its prime. Although would and air leak cause the engine to just up and die while driving?
 
After reading up a bit on the issue, I think air is getting into the fuel. This issue seemed to start in the summer before I rebuilt the engine but I was just shrugging it off as clogged filters. I'm gonna go over all the fittings and see what I can eliminate. It's also possible the fuel filter housing could be leaking too. An input on this would be helpful.
 
After reading up a bit on the issue, I think air is getting into the fuel. This issue seemed to start in the summer before I rebuilt the engine but I was just shrugging it off as clogged filters. I'm gonna go over all the fittings and see what I can eliminate. It's also possible the fuel filter housing could be leaking too. An input on this would be helpful.

My primer/filter unit was leaking air at one point. I bought a generic 'hilux' one off Ebay and it's been good since. Something like this one I think: Diesel Fuel Filter Primer Pump for Toyota Hilux 2L & 3L 23301-54410 | eBay - https://www.ebay.ca/itm/132091034139?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=kgkctxI_T92&sssrc=2047675&ssuid=&widget_ver=artemis&media=COPY

Until you solve the air problem, it's hard to troubleshoot anything else.

If your injection pump was fine before the engine overhaul, I doubt it's failed in the mean time. Usually when they wear out, hot starting becomes very difficult, as the hot fuel passes by the plunger in the head.
 
My primer/filter unit was leaking air at one point. I bought a generic 'hilux' one off Ebay and it's been good since. Something like this one I think: Diesel Fuel Filter Primer Pump for Toyota Hilux 2L & 3L 23301-54410 | eBay - https://www.ebay.ca/itm/132091034139?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=kgkctxI_T92&sssrc=2047675&ssuid=&widget_ver=artemis&media=COPY

Until you solve the air problem, it's hard to troubleshoot anything else.

If your injection pump was fine before the engine overhaul, I doubt it's failed in the mean time. Usually when they wear out, hot starting becomes very difficult, as the hot fuel passes by the plunger in the head.
Just bought that now. Pretty cheap. For now I’ll check all the fuel lines. It’s kinda a pain in the ass to tell if I’ve fixed it because it runs fine in the yard, I can drive it around, only way to tell is to drive it on the road and get into the gears.
 
I just put some clear line to the injector pump. It’s a bit of along video. There’s a little bit of air going through occasionally. But as soon as I turn it off, a ton of air comes out of the injector pump.
 
I just put some clear line to the injector pump. It’s a bit of along video. There’s a little bit of air going through occasionally. But as soon as I turn it off, a ton of air comes out of the injector pump.

love what you have done. you will get there. can't help but laugh upon the contrast of weather, does it always snow there?! we have been over 30c everyday for awhile down here..
 
love what you have done. you will get there. can't help but laugh upon the contrast of weather, does it always snow there?! we have been over 30c everyday for awhile down here..
From October to April it’s miserable up here😂 then in the summer it’s stupid hot. It’s both extremes here. I don’t know how I keep doing it, but I’m always pulling engines in the snow.
 
From October to April it’s miserable up here😂 then in the summer it’s stupid hot. It’s both extremes here. I don’t know how I keep doing it, but I’m always pulling engines in the snow.
at least you know you want to do it! If I ever want it to rain here I just open my bonnet. but geez, work in snow! 😁
 
Good idea to use the clear tubing. I was going to suggest that you put it in the return line but as long as you can see the bubbles you should be good.

I'm not familiar with your engine at all but I worked many years as a diesel mechanic. 15 year of those at a Caterpillar dealership so I can offer some basic knowledge that may help you.

Keep your fuel CLEAN, CLEAN CLEAN. Don't cheap out on filters. Use a water separator. Don't fill your new filters with unfiltered fuel. Use the priming pump or a filtered source. Use an anti gel additive if needed.

Find your air leaks and fix them. Air cannot be in the system. Big leaks and the engine will die. As you know. Small bubbles retard your injection timing. White smoke usually.

Black smoke is PARTIALLY burned fuel. Could be advanced timing, over fueling, plugged air filter, lugging, etc.

White smoke is FUEL VAPOR ( aside from a coolant leak into combustion chamber) Raw fuel for numerous reasons. Could be as simple as your cold temps at startup, bad nozzle(s) over fueling, late timing, etc.

You need to fix your fuel supply first off or you're going to chase your tail. Get clean fuel to your injection pump with no air bubbles.

When you have no bubbles in your supply line, put the clear tubing on the return. Some engines have injection pumps that can suck air at shaft seals. (throttle shaft on some engines) I don't know if your pump is one of them. Also, some fuel systems can get combustion gasses into the system at injector seals. Again I don't know your system. Just something to be aware of.
If you have no bubbles into the injection pump but you have them in the return, find out why.

Late injection timing can give you high EGT's. The fuel is still burning as it's going out the exhaust.

This is just general info. Like I said I know nothing about this engine. I just thought it may help you with your troubleshooting. You have a fresh rebuild so focus on getting your fuel system squared away.

You're a Baddass (or crazy) working in those temps.

Scott
 
I thought of something else. Many old mechanical injection pumps have delivery valves. Basically a check valve at each pump plunger outlet where the fuel line connects. They maintain a minimum pressure in your injection lines so you don't get a delay before firing. You don't want the fuel line to have to fill up on every stroke.

I remember some old pumps that I think the delivery valve would lift at 200 psi. If they are not holding or if you get air in the system, you get problems like you are seeing. You may have to get your pump in for service if you fix your air leaks and still have problems.

Good luck.
 
I thought of something else. Many old mechanical injection pumps have delivery valves. Basically a check valve at each pump plunger outlet where the fuel line connects. They maintain a minimum pressure in your injection lines so you don't get a delay before firing. You don't want the fuel line to have to fill up on every stroke.

I remember some old pumps that I think the delivery valve would lift at 200 psi. If they are not holding or if you get air in the system, you get problems like you are seeing. You may have to get your pump in for service if you fix your air leaks and still have problems.

Good luck.
lots of good info thank you. I should clarify, the clear line is on the inlet side of the injector pump. I will try and source a new pump, I need one with a boost compensator for the future turbo install anyways.
 
I might attempt to rebuild the pump if I can find some information on it.
 
Rebuilding the pump is one thing. Setting it accurately requires some pretty expensive equipment. Each individual pump gets set to deliver exactly the same amount of fuel at the same time (basically) Getting harder to find people that know the mechanical pumps.

There may be backyard methods out there?? I'd just find a good pump shop and let them know your setup/expectations.

Never forget, CLEAN FUEL!! The tiniest debris will sand your pumps and nozzles. You need a jewelers loupe to see the damage but the engine will feel it.
 

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