Black smoke cure wanted

Hi, I am a newbie to this forum so bear with me if I am asking some stupid questions. I recently bought a 52 TD4 Freelander and after a month of having it, the slave cylinder went and costed me an arm and a leg to repair. Since being repaired, I have started to notice excess black smoke coming out of the exhaust when travelling so I went back to the garage and they recommended me to have a full service done on it so I did it but it still gives out black smoke. Can the recent clutch replacement have a cause in this as black smoke were never seen before until now? Keep in mind, this service was done at my local garage and not a LR specialist. I have treated the car twice with the recommended treatment additives but still without any luck. At the same time of driving around, I have noticed that the car is having some sort of an extra push for a fraction of a second and when that does happen a puff of smoke comes out of the exhaust pipe. Is there anything else simple I can try or do I need to go to a LR specialist garage in the Portsmouth to get this sorted?

Anyone got any recommendations on a 4X4 or LR specialist in Portsmouth? Any ideas on how much this would set me back to repair this?

All I want is for my new car to give me a hassle free driving so any advice on this will be much appreciated.

have you tried changing the crankcase breather filter ? won't do no harm, and might just cure it, and if it doesn't it's only £25 spent, and generally worth doing anyway. It's only recently been included on LR service schedules, and doesn't normally get changed on a service. Takes under an hour start to finish for the first time, I'm down to 20 mins now.

tubo inlet rubbers got a small hole/split. . . .youve got three