White smoke 1HZ - solved

[mudgudgeon]

Assuming you have OEM sub tanks? ^^^

Does the issue occur on main and sub tank? Or only one?

IF it only happens on one or the other, you may have an issue with the in tank pick up? Or hose from tank to change over solenoid valves

 

[janyyc]

As I mentioned, any input, however obvious, is very appreciated and welcome.
No, @mudgudgeon, I haven't replaced those (and would rather not think about dropping the tank). There is only one tank on the 76-series.
Though I'm not discounting anything, I have a hard time believing that it's an air leak - if so, why would it only manifest itself sporadically? And why would a cetane booster/fuel additive generally get rid of the problem? When @gnarlynick2072 & @veiloctane came over, we ran a jar of diesel purge and cleared up all white smoke/hesitation (which at that point was horrendous, even at startup).
Relative to replacing those lines above the tank (eek), replacing injectors is a one-banana job, and it doesn't hurt to take those out and inspect anyways.

 

[bcsteel]

Throwing darts here but any chance your fuel tank is pressurizing slightly. If so maybe that’s causing another weak point to suck in air? I’m reaching pretty hard here. Hope you get it sorted.

 

[Squash]

You could try a weighted fuel hose(chainsaw pickup) into a clean fuel container directly to the IP and then go for a rip.
We know that you are smart enough to secure the fuel container....
This will eliminate any guess work. It's either towards the tank or the IP.
I'm guessing towards the tank.
I have also tried using the return line for intake and the feed as a return on some diesels, actually first time was accidental.
Before dropping the tank i would send in a little camera either from the filler or via the tank drain. Sometimes weird s*** does get in.

 

[mudgudgeon]

I had fuel lines sucking in air on my hzj105.

I would say it was sporadic at the start. It was daily driven.
First noticed as occasional power loss, stumble in engine RPM, but otherwise drove fine.
It became more persistent to the point i swapped injectors. Truck ran slightly better overall, but the stumble persisted and was worse in some situations, and white smoke appeared.
I was ready to have the IP rebuilt but was baulking at the cost.
At that point, i did a test with clear hose and found air.

I used a piece of house long enough to go from filter to pump with a loop poking out the side of the hood. Then half latched the hood.
Then took it for a drive. I could clearly see air bubbles in the hose from the driver seat.
Driving it allowed me to replicate situations where it was stumbling. I wasn't really seeing any air with it sitting idling, or revving it with no load.

Mine was stumbling under load. Heav acceleration, heavy throttle on an incline etc

I had a video on YouTube with the hose visible, but its no longer there.

Dropping the tank to change $15 hose sounds better than $600 on injectors and a couple of grand on pumpwork

 

[mudgudgeon]

And why would a cetane booster/fuel additive generally get rid of the problem?

Sometimes we want these things to be the solution so we convince ourself they are.

Maybe they cleaned up injectors a little, and there was an unrelated improvement in his the engine ran.
My guess is it's coincidental that an intermittent air leak stopped while you were messing about with stuff.

Personally, not a fan of additives in general. I'm sure some have their place occasionally, but most are marketed heavily on bullsh¡t.
You buy a sizzle, not a sausage.

 

[sodafeld1]

Guess I'll chime in, my experience is only on a 2h . Once I had a very bad fuel line leak, it was so obvious the engine stalled, could not drive it 5km. Rubber hose replaced, prime, hey presto.

In Oz I only use known good fuel bowsers. From over here I suspect bad fuel or maybe your compensators, they would add another opportunity for air.

It does make a pleasant difference when changing injectors, but I save it for close to the 100k km mark. But i get 9-10l/100km and no smoke so let her go for longer. Liquid moly is lovely , but on new injectors should not be necessary really.

I think it is difficult to work on a car which is not driven regularly, to iron out, fine tune and get a feel for things. You have to try things out, drive it, fiddle around, drive it until you find constant predictable behaviours. Regular, aiming at clockwork predictable. Be methodical.

I would guess if liqui moly works for a while it rules out air leaks. Either bad fuel if you are letting the diesel sit around for months, especially if bad to start with from the bowser. Can just drain the tank and get some clean diesel, look at the stuff before putting it in. If your tank is half full over months moisture in the air in the half empty shall turn to water. Which could be another factor. Always leave tanks full or empty, I prefer full with diesel, empty for petrol on chainsaws for example..

Or at the very least look at what your injector nozzles look like. Fresh nozzles are good for 100k kms, so once done you can rule it out too. When were your nozzles changed out last? Densos are beautiful finely machined things for the price really.
Also, have you just touched with your finger any of your hard fuel lines whilst the car is running? If an unusual pulse can be felt not consistent on the 6 lines, that could be a suspect injector, or leaking line or washer. Diesel works on pressure.

Sorry if I come across as a smarty pants, but you seem to be struggling for awhile with this, so trying to help.

 

[JDM Journeys]

I do wish they'd made the fuel pickup accessible from the back like the fuel level sender. Dropping the tank isn't a lot of fun.

But if you want to do it, I'll give you a hand. Ratchet straps helped a lot...

But I'm still inclined toward injectors esp given that DP helped. When mine was producing "the great smoke show" it was always on cold startup, after sitting, when air got drawn in (from the fuel pickup).

 

[janyyc]

I’m still chasing the white smoke devils…
Haven’t driven it much over winter, but the weather has improved and snow has melted. Drove 170km, mostly on highway at around 100km/h. No smoke or stuttering.
Parked up for an about 6 hours. Fire up, puff of white smoke and then more smoke when pulling away. Highway driving on the way back fine, no stuttering or noticeable smoke, including downshifting for hills. But accelerating from a stop at the first set of lights, smoke show and stuttering at mid-RPM’s until past about 2K (I don’t have a tach but know the 1HZ from my other vehicle).

OK time to fix the problem.

Together with @JDM Journeys we set up a course of action to eliminate causes one by one.

Firstly I put a 3/8” ID clear hose between the main fuel tube and the injector pump, bypassing the filter entirely. Go for a drive and run some errands. First drive goes off without a hitch. Then the second one the stuttering and smoke returns - open the hood, verify that even at full throttle there is 0 air in the line.

Second step, drain some fuel from the tank to see if there’s any sediment. Managing to make only a little bit of a mess on my driveway, I verified the fuel is clear and there is no sediment present. Not as conclusive as dropping the tank but at least something…

Third step then is to replace the injectors, which I had already ordered as a preventative measure. Tonight I managed to remove them and inspect. The worst is #3, with #1 and #2 also being dirty and wet.

From 1-3 in order.

A close up of #3 in hand:

Tomorrow I’ll install a full set of fresh Denso injectors. Tonight I’m saying my prayers this solves my problems

Oh and on a more positive note, here’s a picture from my drive the other day.

 

[veiloctane]

Pump timing? Run more hotshots thru it?

 

[janyyc]

Pump timing? Run more hotshots thru it?

The problem goes away when I run LiquiMoly or similar, yes. But just a little in the tank actually isn’t enough.

Also I should add my fuel economy is pretty bad. 13.7L/100km. My Troopy gets about 12, even when fully loaded…

But remember @veiloctane when you visited you listened to one of the injectors with a wrench and said it didn’t sound right. IIRC it was #3…

 

[bj70bc]

could you be getting air post clear tube....

 

[janyyc]

could you be getting air post clear tube....

That would mean injector pump… and that’s next on the list I suppose. But I hope I don’t have to go that far.

 

[lowenbrau]

That would mean injector pump… and that’s next on the list I suppose. But I hope I don’t have to go that far.

I have a rebuilt pump that I can loan you for troubleshooting if it comes to that. If you love it, you can buy it, if not I'll know it has been tested.

 

[veiloctane]

The problem goes away when I run LiquiMoly or similar, yes. But just a little in the tank actually isn’t enough.

Also I should add my fuel economy is pretty bad. 13.7L/100km. My Troopy gets about 12, even when fully loaded…

But remember @veiloctane when you visited you listened to one of the injectors with a wrench and said it didn’t sound right. IIRC it was #3…

Well you can replace or rebuild maybe crack test the pressure on #3 I’m curious maybe a broken spring or it’s clogged. Good luck.

I just did a rebuild of my pump and injectors. And mine still smokes on occasion depends where I get fuel from.

 

[janyyc]

OK, injectors swapped. Did a test drive, not very long, but everything seems to be good. Probably confirmation bias, but engine seems to crank faster, pull better, sound quieter... Tomorrow I'm going to the airport early morning, my dad will drive me and back so that'll be a good test if things have improved.

Got all the old seats and washers out using a hook tool I had back from the days I would repair my own iPods (!).

Nice to have the "bible" in front of you when working!

All buttoned up...

Gratuitous test-drive shot...

@veiloctane which stations give you "better" diesel?

 

[veiloctane]

OK, injectors swapped. Did a test drive, not very long, but everything seems to be good. Probably confirmation bias, but engine seems to crank faster, pull better, sound quieter... Tomorrow I'm going to the airport early morning, my dad will drive me and back so that'll be a good test if things have improved.

Got all the old seats and washers out using a hook tool I had back from the days I would repair my own iPods (!).

View attachment 3881137

View attachment 3881152

Nice to have the "bible" in front of you when working!

View attachment 3881144

All buttoned up...

View attachment 3881147

Gratuitous test-drive shot...

View attachment 3881150

@veiloctane which stations give you "better" diesel?

You can try premium diesel at shell or husky. But don’t forget to add your lubricant because of ultra low sulfur diesel.

And don’t fill up when there is a tanker at the station. I was told that when the pumps are refilling it stirs up the sediment.

Since you’re going to the airport there is a shell station up there.

 

[janyyc]

I mean, we’re speaking of a 1HZ. It should run on melted plastic bottles for heaven’s sake.

 

[veiloctane]

I mean, we’re speaking of a 1HZ. It should run on melted plastic bottles for heaven’s sake.

Just because It can doesn’t mean it will run well.

 

[veiloctane]

What troubles me about yours is yours has very low KMs last time wasent it around only 25,000km

Every 150,000 to 200,000 km is injector service. And your is so far from that.

So what caused this issue water in the fuel or contaminated dirty fuel? Would be nice to know the root cause.