Replaing Tdi300 engine with TDi200 engine?

Hi, I have a Tdi300 whose engine has developed a high back pressure coming through the breather hose.

|I presume I will need to overhaul this engine. if so, I would rather look for a Tdi 200 engine which I find more quiet and reliable. Any place where I can get a used engine?

At the same time, I understand that a Nissan QD32 engine makes a good substitute and fits with minor modification.

Is it possible to get feedback on both options?

Regards.

The 300Tdi is generally considered more refined than the 200Tdi, so you must have been comparing against a particularly tired 200Tdi. The 300Tdi is very reliable indeed, so long as you keep on top of basic servicing, and don't let the coolant run low.

The 300Tdi has slightly more power and torque than a 200Tdi, and even more so if you get one out of a discovery automatic.

But, to replace a 300Tdi with a 200Tdi, there's a quite a bit of work
1) Engine mountings are different, including the brackets on the chassis
2) Exhaust arrangement is different, particularly if your trying to fit an ex discovery 200Tdi into a defender
3) Radiator is different (top hose entry is a different angle)
4) Intercooler might be different although offhand I'm can't be sure

Its all do-able, but really your far better off to try and find a replacement 300Tdi . The other thing to consider is that parts availability is better for a 300Tdi.