Thread: BJ73 Landcruiser

Originally Posted by veitnamcam

Has it always smoked or just started doing it?

Black smoke is poorly combusted fuel due to either poor atomisation or simply not enough oxygen in the chamber.

How bad is the smoke? It is an old school manual injection diesel and it should smoke lightly under full power,clouds of black smoke so thick people behind you cant see or breathe is another matter tho.

Bad smoking could be caused by restricted intake, worn/damaged injector nozzles or incorrect crack off pressures or if it has been like it since you got it?if so then most likely someone has adjusted max fuel for more power.

Its coming into summer and the air is less dense as it warms up, it makes a noticeable difference in power/smoke on old N/A diesels

Not knowing previous history I would.
Check/clean/replace air filter as required.
Go to a bigger pipe between those silicon fittings in the intake just in case that is restricting it.
Replace fuel filter (you did that already?)
Pull the injectors and get them serviced.
Check/clean gauze filter in pump if so fitted.

Then when everything has been serviced and is as it should be clime a hill where it is working hard at highish revs in 3rd, on a sunny day there should be just a slight haze behind you, clouds of heavy black smoke is bad if you still have this adjust max fuel down....your Idle speed will drop if lessening fuel and raise if increasing fuel....1/8th turn should be noticable 1/4 turn is heaps.

I never noticed it smoking until I had the IP seal done, since then it's pretty bad - in both warm and cold weather.

I've changed fuel and air filters, and to check if it was due to restriction with the silicon intake hosing I pulled the intake piping and ran it with just an open throttle body, same result.

Valve clearances were the only other thing I could think of to check myself before taking it to someone to look at the injectors. I did notice that the idle is higher since the seal was done, so possibly the fuel was turned up? I'm getting noticeably worse economy than previously too