leaning out my 13B

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Apr 16, 2014
So i am very new to owning a diesel LC. I have an 85 BJ74 that i feel is running a bit rich. It has black smoke at start up which I've read is normal but as i drive it i can still smell unburnt fuel. Is there something i can do to lean the mix?
Get an exhaust opacity test done before you trust what you think you smell. Any competent diesel shop should know how, and they can make the necessary adjustments if required. The ND IP is a Bosch clone, so most diesel mechanics are familiar with the fuel adjustment.
Is the air filter clean? As it's a new to you truck, thought I'd ask.
If u can smell diesel maybe u have a leak somewhere thats only present once the fuel is under significant pressure. Check fuel lines, soft and hard. Unions on injectors and fuel rail etc
everything on the truck has been redone. this is the truck i bought and the build thread. Not saying there are not a few gremlins here and there that need to get smoothed out though..

Diesels don't run a mixture like a petrol engine does, Every stroke a diesel takes in a full "breathe" of air then fuel is added (the amount of fuel injected is independent of the amount of air taken in, generally speaking). More fuel = more power, if you reduce the amount of fuel injected you decrease the power output so less fuel has the same effect as letting the accelerator up a bit.

As for your smoke, fuel pumps go to full fuel position for starting so don't get concerned about the initial black smoke.

The smell is a bit harder, all diesel exhaust still smells of diesel a bit. Without driving the car it will be hard for us to help much. Sorry.
everything on the truck has been redone.
Does that include the injectors? Once the nozzles are worn nothing can stop them from making black smoke. Its around $600 so if anyone is selling its unlikely they would do them before they sell.
When they are worn, they dribble drops of fuel onto the piston causing black smoke as the throttle is depressed
Its a 100000klms service interval .They are removed from the engine ,spray pattern is observed and cracking pressure is noted. Then are reconditioned with new parts and retested. Usually the injector pump settings are adjusted as part of the service if they remove and instal the injectors. My shop also dynos the engine to check the HP.
Most shop in Australia can do these with their eyes closed.
injectors were redone. not sure on the other adjustments.

I'll find a good diesel shop here and have them go over it. Right now I'm trying to get a damn Voltage reg which is damn near impossible.
Not sure whats available over there.. would it be easier to find a 24V internally regulated alternator?
I've read that there is one out of a Isuzu trooper that would fit in but there are some modifications to be done.

Users who are viewing this thread

Top Bottom