help diagnose weird excessive smoking. (1 Viewer)

[brisveganbj42]

hi guys, some might recall that i recently replaced a 3b-t with a 15b-f. since then its been running pretty good with the only issues being a leaky top seal on the inj pump. ive also fiddled with the fuel screw but pretty much put it back to where it was originally.i say pretty much because even now it is overfueling a bit. its not rolling coal but noticable in the side mirror under load.

today i pulled the first real load of about 1ton of firewood. everything was going ok and i was taking it easy. theres a 2 long hills to get up to the house as we live near a ridge line. The last bit of the drive way is a right angle at the top of a long sweeping uphill bend.

I kept it in 2nd since the start of the first hill and it smoked a bit more than usual getting up there.. speed was pretty moderate up to the last corner but as its loose gravel just made sure the rpms were up...

the engine seemed to have a bit of a tick coming up to the corner, it then dumped a big plume of black smoke followed by a real dense while smoke which lingered in a large cloud.. i popped the hood to blip the throttle trying to see if i could reproduce it but couldn't.

Water temp was about 185f on a 82c themostat at the top of the hill, didnt check the oil pressure tho

I fumbled with my phone to try and get a photo of the cloud but it had dispursed a bit by the time i took this photo

from what i know about smoke colors, black is over fueling.. bit confused about the sudden onset of white though, always thought it might be a air in the fuel or a head gasket?

I still need to adjust clearances, confirm the timing and check radiator for oil, etc. not sure what else it could be something munted in the injector pump..

I did refuel this morning too but not sure if it could be related.

Any ideas would be appreciated.

 

[brisveganbj42]

Research suggests its all fuel related, white smoke is raw unburnt diesel. I'll get a dial gauge so i can do timing, then all the other bits i need to check.

 

[ozcrusier]

I'm thinking head gasket problem

 

[brisveganbj42]

I'm thinking head gasket problem

How would i verify that?

 

[lostmarbles]

Refresh my memory... What did you do with the fuel-return line back to the tank?

I'm just wondering whether somehow your fuel system is over-pressurising and this is somehow responsible..

(Shot in the dark)

PS. Certainly is a tad smokey...

Edit (and hour or so later): Bit of a brain fart here really because I can't see how excessive pressure inside the IP could have any effect on the quantity of fuel being injected anyway.

 

[brisveganbj42]

No bubbles or oil in the coolant. Seemed to operate normally this morning.

 

[brisveganbj42]

Refresh my memory... What did you do with the fuel-return line back to the tank?

I'm just wondering whether somehow your fuel system is over-pressurising and this is somehow responsible..

(Shot in the dark)

PS. Certainly is a tad smokey...

Ran a 7mm hose all the way back to the vents at the filler neck.

 

[RufusTheDufus]

Did you happen to install a ProVent oil separator/catch can? I had an engine smoke like that after a similar driving situation and it turned out to be the ProVent failed. I think it wasn't able to drain back to the sump and crankcase pressure built up/ There's supposed to be a one-way valve and pressure relief but it failed allowing engine oil to make it into the intake. It was like flipping the smokescreen switch on the dash, except I don't have a smokescreen switch. Oil in the intake can seem like unburned fuel.

 

[Wheelingnoob]

Sorry your engine temp got to 185c? That is supper supper hot if not a type o.

 

[elkaholic]

Agreed ... That's even a bit on the warm side for oil temp.

 

[lostmarbles]

Ran a 7mm hose all the way back to the vents at the filler neck.

Never mind. I don't think it could really cause this smoke issue even if you had no return at all.

(I rushed into that post without thinking enough.)

I like Rufus's idea above though. That sounds very plausible to me... (and I'm assuming 185 oC was meant to be 85 oC (or else you were thinking in Fahrenheit to suit those in the USA).

 

[brisveganbj42]

Sorry your engine temp got to 185c? That is supper supper hot if not a type o.

Typo sorry! 185F!

 

[brisveganbj42]

Also on the way home I dropped down to second gear with no load up the first of the two hills and was able to reproduce the smoke.. I'll get the go pro sorted and attempt to get some video

 

[brisveganbj42]

Did you happen to install a ProVent oil separator/catch can? I had an engine smoke like that after a similar driving situation and it turned out to be the ProVent failed. I think it wasn't able to drain back to the sump and crankcase pressure built up/ There's supposed to be a one-way valve and pressure relief but it failed allowing engine oil to make it into the intake. It was like flipping the smokescreen switch on the dash, except I don't have a smokescreen switch. Oil in the intake can seem like unburned fuel.

Wouldn't that be similar to blue smoke.

The 15b-f has a vent tube on the rocker cover going into the intake. No catch can. I can verify via the intake hoses if there is any oil there..

 

[brisveganbj42]

got a video but my upload speed is poo.. i was doing about 3000rpm in 2nd when it happened. i trired in first and couldnt reproduce it up to 3500rpm.. oil pressure and water temps both normal

 

[brisveganbj42]

the bit im curious about is about the 45sec mark.

 

[BEE-JAY42]

Just to clarify and it may help you out, black smoke is fuel burnt with a lack of oxygen (too much fuel or not enough air), white smoke is the result of low cylinder temperatures. White smoke can be caused by many different things but the most common causes are injection timing ( injecting too early before the cylinder temp is high enough or too late after the cylinder temps have peaked and dropped off), low compression or massive over fueling.

When people post smoking issues you get heaps of people jumping on here with random guesses at the issue and they are usually pretty bloody scary for the original poster, unless someone can give you an explanation of why they think it is what they are saying it is and how you can test their theory I would shy away from following their suggestion.

Back to the actual problem, is there a noticeable loss or sudden increase in power when it happens (also I can't see your video, could you post a link please)?

 

[Wheelingnoob]

OK so not a Toyota engine but on my Isuzu 4bd1t when I got it running after a rebuild I ran it. It would idle totally fine and when I reved it quickly it was fine. If I slowly raised the Rpm though it would start doing that. It was kind of like a popping miss and tones of white smoke. I ended up having the pump looked at and it was found that a barrel was out of sync with the rack. The injection shop said it was my problem and it's not done it since.

Not sure if that is your issue but it sure looks like the same thing mine was doing.

 

[lostmarbles]

Watching the video it sure sounds to me that it is missing (not firing) when the plumes of white smoke appear (which would explain the white smoke as unburnt fuel).

It could be compression-related with an exhaust valve somehow sticking open only at those high revvs (which seem rather unlikely).

I don't know exactly what the person advising Wheelingnoob means by "barrel out of sync with the rack" but if something is happening inside the IP that suddenly retards the injection timing of one or more cylinders this would certainly cause the white smoke.

But let's look at the simple solutions............

A clogged fuel filter will produce white smoke at high rpm (2000-3000) according to Toyota:

 

[brisveganbj42]

Watching the video it sure sounds to me that it is missing (not firing) when the plumes of white smoke appear (which would explain the white smoke as unburnt fuel).

It could be compression-related with an exhaust valve somehow sticking open only at those high revvs (which seem rather unlikely).

I don't know exactly what the person advising Wheelingnoob means by "barrel out of sync with the rack" but if something is happening inside the IP that suddenly retards the injection timing of one or more cylinders this would certainly cause the white smoke.

But let's look at the simple solutions............

A clogged fuel filter will produce white smoke at high rpm (2000-3000) according to Toyota:

View attachment 1120881

Thanks. The filter is new however I've been told that the quality of diesel has been a bit suspect around here lately so it could be something to look at.

OK so not a Toyota engine but on my Isuzu 4bd1t when I got it running after a rebuild I ran it. It would idle totally fine and when I reved it quickly it was fine. If I slowly raised the Rpm though it would start doing that. It was kind of like a popping miss and tones of white smoke. I ended up having the pump looked at and it was found that a barrel was out of sync with the rack. The injection shop said it was my problem and it's not done it since.

Not sure if that is your issue but it sure looks like the same thing mine was doing.

THanks for the suggestion. I've got the diesel mechanic who did the top seals on my phone so i'll flick him the link to the video and see if he concurs with your proposal.