Hi, simwood91.
The invitation to Ukraine for repairs was like a joke, but if you came, I would have made repairs.
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A light smoke is a sign of late injection and / or a very high oil consumption.
How much oil does your engine use per 1000 kilometers or 500 miles?
Or a more correct statement of the question: how much oil does your engine use in relation to fuel consumption?
If the oil consumption is more than 1% of the fuel consumption, the motor needs to be repaired or changed.
All atmospheric motors MK3, MK4, MK5 have the same design and identical parts inside and are interchangeable.
On your MK3, no problem can be installed any Ford Transit MK4 or MK5 engine.
With some modifications, turbo engine MK3, MK4, MK5.
The engine MK3 from the subsequent MK4 and MK5 differs in that the oil pump has three fixing bolts, and the ones five.
There are three or five holes in the block, three or five bolt samples in the transition plate.
There is a difference in fixing the motors MK3, MK4 and MK5.
Other "paws" and pillows.
In very old MK3 motors may not be a place for the fuel booster pump.