2002 316I Se Engine Replacement Advice

[jimmy3000]

Hey, just bought my first bmw after seeing how well family and friends cars run and look.
A 2002 316i se the car is very clean inside and out and the engine *looks* perfect. There is not even any rust in the arches.. it drove well with no problems for around 2 weeks.

Then the engine management light came on and it started leaking oil slowly from the bottom of the car. I replaced the oil and took it to my mechanic. He explained something along the lines of the timing tensioner screw being stripped, oil coming from behind the bolt, also there was silicone sprayed in where the timing chain is and it being a really big job any where from £200-£1000. He sealed the leak with chemical metal and told me it might do for a while. I drove it to work and back and on the way home the car lost all power and barely made it home, now with the oil light on and flashing on and off when the foot is put on the accelerator. There was also a noise coming from the left hand side of the engine, i think it is a vacuum pump.

I don't know much about the above but i do know the engine was already very weak in power and have read that this is an issue with the 316.
I'm, thinking of just replacing the engine and was wondering is it possible to put a bigger engine in with out changing the gear box or anything else for example? Or would it be better to get the same engine again fro cost and time etc.

Thanks for any help anyone can give, not really sure what do or if a repair is really a cost effect option compared to replacing the engine.

[jimmy3000]

saloon E46 September 2002 and its a 1.6 se i think thats 105 bhp