300 tdi -loads of smoke at 2500rpm

If I describe a sequence of events I would appreciate some opinions.

Disco 1 with 300tdi snapped the timing belt. Belt was replaced after which lots of smoke. Then checked and found conrods bent so replaced them with new.
Still lots of smoke .
Got a new old stock never fitted cylinder head so bought it as very cheap. New valves fitted as well. Found 2 cracked cam followers so they were replaced.
Still smoking.
Fuel pump timing checked and also timing cover removed to double check belt and although pump timing was very slightly out it was adjusted.
Still smoking.
It smokes really bad (seriously bad!!) at 2500rpm and on full throttle is almost clear.
Prior to belt snapping it was spot on.

Any suggestions?

Cheers....

Is the smoke due to fuel or oil?

Al2O3 said:

Is the smoke due to fuel or oil?

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Apologies for the delayed reply; i have been away!
The smoke is white/blue in colour

I assume you mean you replaced bent pushrods rather than conrods.
Does it start easy and tickover smoothly? And how well does it drive?

Kev12 said:

I assume you mean you replaced bent pushrods rather than conrods.
Does it start easy and tickover smoothly? And how well does it drive?

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Apologies, yes it was the pushrods!!
It starts no bother but for maybe 10-15 seconds it's a bit rough then takes revs and is smooth. At idle smoke is not too bad, revs held steady at 2500rpm and it's chronic but full revs there is no smoke

I am just back home after being away most of the past 3-4 weeks.
I started it up and fires into life instantly, runs smooth so assume that is after the fuel pump timing being set.
2500rpm loads of smoke and hold it at 3500rpm and literally no smoke.
I took the intercooler pipe off at the turbo and there is oil smeared on the pipe...

The oil is likely nothing to worry about, you always get some in there.
Its a confusing one as it must be related to the belt snap/replacement but you seem to have covered the obvious things.
Pump timing wouldnt cause as huge an amount of smoke like you described. Have you had rocker cover off again and checked valve clearances since it has been started?
Any chance when you reassembed the engine that you swapped over any banjo bolts? One of them has restricted flow

I know, that's my own thoughts that it's related to the belt snapping or replacement. It's a mate that's doing the job and we have had the rocker cover off several times and he has checked the valve clearances a few times now. It's strange how at the different revs the smoke is so different!! The smoke was the same after the belt replacement, then on getting a brand new unused cyĺinder head at a good price we fitted it with new valves and pushrods, new glow plugs and the smoke is still the same.

Is it impossible to drive due to the smoke you leave behind?
This is oil in my top intercooler pipe.
This is after everything has cooled down and the oil vapour has had a chance to condense, gather on the shiny silicone tube and settle up against the lip of the top intercooler tube. Pulling the pipe off the intercooler creates the oil lines. It's not always as bad as this. My turbo is passing a lot of oil. It doesn't collect much more oil that that shown. This is because it comes out of the turbo so atomised that it blows straight through the intercooler and in to the engine. As it heats up, which the turbo does quickly, the oil vapour blows through even easier. The intercooler doesn't cool it enough to make the oil condense and pool in the bottom of the intercooler. The exhaust is black and sooty, but the smoke that comes out of mine is quite light in colour.