80 series turbo blown? (2 Viewers)

[Bonsnz80]

Hey guys,

Hoping you can help, I have a 1996
Land cruiser 80 series 24 valve. I've owned it for about a year now, when i purchased it it had high egts, puffed a lot of soot and was at 16psi boost but it had pretty solid power.
However, recently I've turned down the fuel and its egts are still pretty high and it struggles a lot up hills (slowing down but foot flat) its still boosting 16psi. The worst part about all this is it keeps getting slower.

When i say its slow 3L hilux surfs are pulling on it.

 

[mudgudgeon]

Are all the basics ok?

Clean air filter?
Clean fuel?
Clean fuel filter?
How many kilometres?
How recent was timing bent changed?

What EGTs are you seeing?
If you keep your foot buried in it, what's the EGTs peak at?

Is the EGT probe in the manifold? Or after the turbo?

Stock turbo?
Stock exhaust?

Describe when you see smoke?

 

[Bonsnz80]

Are all the basics ok?

Clean air filter?
Clean fuel?
Clean fuel filter?
How many kilometres?
How recent was timing bent changed?

What EGTs are you seeing?
If you keep your foot buried in it, what's the EGTs peak at?

Is the EGT probe in the manifold? Or after the turbo?

Stock turbo?
Stock exhaust?

Describe when you see smoke?

Timing belt hasn't been changed in my ownership so that could be it but the air filter and fuel filter are both clean,

Egts are after the turbo and peak at 650c

Kms are 345,000

3 stainless stripe exhaust however still on stock turbo, turbo definitely makes a bit more noise than it used to (could be bearings)

Smoke is if it gets revved after being on idle for a while. It will puff soot then make like a pop with white smoke (sounds almost like a hardcut)

 

[mudgudgeon]

A few things to look at

EGT probe after turbo is useless and gives a very deceptive/false reading
Your 650c after turbo could be anything from 650-900 measured in the manifold where it matters.
There's a big temperature variable across the turbo that is not constant. EGT probe is easy to install after turbo, but is really not the best. If 650⁰c was the highest EGT you were seeing measured BEFORE the turbo, I'd say fueling is OK. Measured AFTER turbo, could be borderline "cook the engine" too high. But, it's a guess at best.

Stock turbo.
At 16psi, you're pushing the friendship with the stock turbo. After 15psi, all bets are off! It's working outside its efficient range. It will be heating the intake air A LOT. And, they can self destruct ( BTDT) you're losing the compressor beyond what the material is designed for.

Noisy turbo
If the turbo had gotten noisier than normal, or is howling/whining at all, it's a plea for help. Stop driving it. Check the turbo compressor wheel for play. If bearings are worn, and the compressor touches the housing, your engine will be eating turbo fins for supper.
Start looking at replacement or rebuild options NOW! STOP DRIVING IT.
You're on a path to destruction ( BTDT)

Smoke
If it blows blue smoking after a blip of the throttle after idling for a while, it's most likely got leaky valve stem seals. A simple test for this is to coast down a long downhill grade (in gear), as you get on the throttle again after the road flattens out, is there a puff of blue-ish smoke? Blue smoke here suggests valve stem seals are on the way out.

If you're tuned correctly, you'll typically see a puff of black smoke when you come off idle. Example, with the car stationary, if you stab the throttle 2/3 of the way to the floor and release (1-2 seconds) you should see a puff of black sooty smoke, that clears up as revs come up, and turbo boosts a bit ( not blue smoke, not white smoke)

White smoke & hard cut
A puff of white smoke and the hard cut you describe, with almost 110% certainty says you have air getting sucked into the fuel system.
This could be a hard & loose or cracked rubber fuel hose connection that sucks in air without leaking fuel. Could be a badly fitted oring on fuel filter, or could be a leaking priming pump assembly. All very common.
The fuel system is under vacuum all the way to the infection pump. A small crack in a fuel line can suck air.

Do a search in Diesel Tech / 24 volts - https://forum.ih8mud.com/forums/diesel-tech-24-volts.24/ for "air in fuel" "clear pvc" " stumble" etc.

Air in the fuel messes up the fuel injection timing. The air compress in the injection libes, and delays the injector from crackingbopen when it should.
You'll be down on power, use excess fuel, feel it running rough on acceleration, and see stinky white smoke out the back.
The smoke will stink of raw diesel, because the diesel is being injected at the wrong time, and isn't being burnt effectively.