Confirm My Smoking Diagnosis
Turbo Mini Forums

The Sprint has a terrible smoking habbit, here are the symptoms

Only when engine hot
only when at idle
Not when cruising or under boost
Not all the time (but more often than not)
Smoke is oil and lots of it (enough to make the car dissaper!!!)

All new rings, new valve stem oil seals, no excessive oil in IC tubing etc.
The turbo has no real play in any dierection, it's an IHI ballbearing turbo with no water cooling (that is it only has oil fitments on the housing)

So, My guess is that the oil seal to the turbine is FUBAR. My other thought is that the oil return is restricted, but I'd heva thought that if this was the case it'd smoke from start-up and continue. also I'd expect oil in the IC piping.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

I had exactly the same at Avon one year mate, was the oil seals in the turbine.

When under pressure the oil is obviously held back but when idling it looked like a smoke machine!

1/4 Mile 14.3secs 96Mph Terminal 10psi of boost.


Fibreglass Parts? - http://www.tdkracing.co.uk/
Split Rims? - http://www.force-racing.co.uk/

Ref: oil return, in the past I have found that unless it is severly undersize or restricted, it will smoke when cold and then stop once the oil warms up and thins out.

Yes you have it in one wil your prognosis is right,

Check toms advice Out first.

Has a quote for a rebuild £300, that twice what the turbo cost!!

Rebuild kit on the way. I've done a T3 before wuith success, so should be ok.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

Do you have a restrictor in line for the oil feed. Sure I have read somewhere that BB turbo's tend not to like much more than 25psi of oil pressure. Perhaps this could have contributed to premature seal failure.

If something is worth doing, it's worth doing half of.

when i was having my smoking issues (found out to be the oil return entering the engien below the oil level) it caused smoking at idle, never right away, and regardless of hot or cold. if ran for a while eventually the turbo oil seals gave out. Would defo fit a restrictor to the oil feat for a BB core, but be carefull as some cores have restrictive orifices in the inlet in the core.

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.