4JB Engine, black smoke.

[Davehillbo]

Hi all, thanks for the advise in the last thread, got the wastegate and hissing problem sorted!

Now im moving onto the black smoke problem im getting, basically as I increase throttle, the more black smoke I get, and it seems to get worse with engine load (higher gears). Ive checked the airfilter and its not that, what else could it be? No smoke when idle (does smoke white first thing, but not much at all, and clears when warm). Also, the fuel pump appears to be a HEP-02A, is this correct for this engine ?

Many thanks!

David.

[justinc]

I would say somebody has wound on some more fuel to get more power. Black smoke is excessive fuel delivery, not enough air.

This is very dangerous for diesel engines as the exhaust gas temperatures can become high enough to destroy pistons, turbochargers and cylinder heads.

There should be a tamper proof cap on the fuel enrichment screw at the rear of the pump, if you could post some pics of the pump where the fuel injector lines come out of the rear of it, we can show you the main fuel adjustment screw.

JC

[Davehillbo]

https://fbcdn-sphotos-d-a.akamaihd.net/hphotos-ak-ash4/1008663_10201521734393052_1059971282_o.jpg

[justinc]

Back of the pump would be more helpful....where the actual steel injector lines go in.


Here, try this;

Holden rodeo 2.8 td fuel screw - YouTube

JC

[Davehillbo]

https://fbcdn-sphotos-g-a.akamaihd.net/hphotos-ak-ash3/946431_10201521796794612_206480256_n.jpghttps://fbcdn-sphotos-f-a.akamaihd.net/hphotos-ak-ash4/1001841_10201521792834513_1690186887_n.jpg

[Davehillbo]

I couldn't get my bearings on that video lol, is he referring too the little screwhead next to the bigger one on the second pic?

[justinc]

See above link Dave, as you can see in your pics, someone has wound her up.... Start with unwinding it half a turn, and check smoke and boost pressure. I would really recommend fitting a pyrometer to the vehicle if you are intending on playing with fuelling etc. It is easy to overdo it.

JC

[justinc]

I couldn't get my bearings on that video lol, is he referring too the little screwhead next to the bigger one on the second pic?

Yes, the bigger one is a bleeder. And you really should tighten up your transmission throttle cable...:)

JC

[Davehillbo]

Do you turn it anti-clockwise with a flatheaded screwdriver? how far out is it meant to be?

[Davehillbo]

Haha, REALLY appreciate your help bud, never worked on these before, always been more modern engines :)

[justinc]

Yes, loosen the locknut and undo with a flathead screwdriver. Every pump is individually calibrated, so not all fuel screws will be in the same place.

JC

[Davehillbo]

Well well well, adjusted the nut, and the black smoke has reduced! Just taken her for a drive and it seems a lot better. First attempt I think I ran it a bit lean, didn't like being at junctions in drive, fine tuned and now seems a lot better!

[Davehillbo]

Well, It appears that overfueling wasn't the problem, still have black smoke on hard acceleration/load.

any other ideas? lol

BTW.
Boost pressure is about 12psi at full acceleration.

[Bush65]

Well, It appears that overfueling wasn't the problem, still have black smoke on hard acceleration/load.

any other ideas? lol

BTW.
Boost pressure is about 12psi at full acceleration.
Fundamentally black smoke results from incomplete combustion. There are a number of issues any one or all, may be your problem.

Usually not enough air to burn the amount of fuel that is injected. Over fueling can cause this, or on the air side, faulty turbo or turbo adjustment, boost leak, exhaust (turbo side) leak, restriction in air filter or intake, restriction in exhaust system.

Fault injector - spray pattern giving poor atomisation of the fuel.

Low engine compression.

[justinc]

Just how much black smoke???? Alll those earlier 4JB engines aren't very 'clean', especially under full noise, and I forgot to mention the fact that someone may also have adjusted the star wheel and boost enrichment inverted cone in the top cover of the pump....where that pressure line goes in that you teed into for the boost gauge. You can remove that cover and take a gander to see if the diaphragm has been rotated round. Just mark its position before removal.

JC

[Davehillbo]

Well, it pumps out black smoke (dissipates quickly) when traveling at speed (70mph+), can see it out of wingmirror, and extents for about a foot maybe before its disopated? Also does it if I boot it at a junction :)

David.

[justinc]

how far is your foot down at 70mph???? if it is near the fuel max delivery position then yes, you should expect some smoke. try reducing the fuel screw setting a bit more, if there is a bit of an idle issue after that just adjust the idle stop screw to bring it up.

it sounds like someone has done a lot of fiddling with the pump.

jc

[Davehillbo]

It depends on the situation, but usually with my foot down it will do 90mph, as soon as you let up off the accelerator the smoke dies down. What idle RPM should the engine be set at? I don't think it could really be set down any lower, the engine starts to judder at junctions when in drive.

David.

[justinc]

some of the problem is the torque converter it is to suit a petrol v8, so has a low stall speed. in 'drive' at rest you will need to increase the idle speed via the throttle stop screw, and it is also more than likely why the fuelling was altered in the first place.

jc

[Davehillbo]

Haha, many thanks!
Ive noticed it smokes when it gets to about 8psi upwards if that's any use.
Thinking I may take it into a diesel specialist and see what they think, im not confident to really start fiddling lol.
where is the throttle stop screw?
David.

[justinc]

sounds like the boost compensator on the pump has been adjusted, too. this adds extra fuel under load/ boost. if you rotate the diaphragm it is attached to an inverted eccentric cone that the fuel governor pin runs against inside the pump. as the diaphragm is forced down under boost, it enrichens the fuelling. this is very adjustable and allows lots of performance enhancements. will cause smoking if rotated too far, and the spring that the diaphragm pushes against is adjusted via moving its seat (commonly referred to as the star wheel) down to bring in boost fuelling earlier.

this is an instruction pdf from thermoguard instruments. Ian, thank you:))

http://www.landroverweb.com/Pdf-files/Tuning_Land_Rover_Tdi_engines_Rev_2.pdf

this is basically exactly the same as your pump, at least the adjustments are the same type and do the same things:)

jc

[Davehillbo]

Haha, I think that's beyond me now!
Im ok with the basics but anything else , don't want to bugger anything!

Really appreciate the thought u put into this for me bud.

David.

[Davehillbo]

One last thing, How do you adjust idle RPM?

[justinc]

There is a screw that sits against the throttle lever at rest, it is long and has a locknut. Just opposite it the other side of the lever is the full travel adjustment, do not touch that.:D

JC

[Shingleback]

There is a screw that sits against the throttle lever at rest, it is long and has a locknut. Just opposite it the other side of the lever is the full travel adjustment, do not touch that.:D

JC

Mine revs high at idle too, have adjusted throttle stop as above all the way off but still revs high, now what? Are thinking it may be a side effect of the fuel screw being all the way out? Any ideas?
Cheers, Andrew.

[flagg]

Mine revs high at idle too, have adjusted throttle stop as above all the way off but still revs high, now what? Are thinking it may be a side effect of the fuel screw being all the way out? Any ideas?
Cheers, Andrew.

The fuel screw usually only comes into play in terms of how much fuel is delivered at max throttle.

For a 4bd1 at least you need a higher than normal idle or you will get your teeth shaken out at the lights.

[Davehillbo]

Tachometer says im idling at 500rpm, but I have no idea if its accurate!