jvrenaudon
Well-Known Member
My Series 2 CSi VIN 4350022 was laid up outside in the open before I acquired it in 2014 at 87000 miles. The head was cracked and the injectors were missing. I have been unable to trace the previous owner but the bills which came with the car suggest that there had been an on-going overheating problem with the car before it was laid up. When I got the car I removed the head and the bores looked ok - a bit of ear on the thrust faces but I have seen far worse. I therefore fitted a replacement, re-conditioned, head. On start-up, after a few miles, the Compression test readings were N0 1 125, Nos 2,3,4 and 6 150 and No 5 155. However, it was pretty smokey at anything over 2500 rpm when under hard acceleration load. However, I noticed a gradual reduction in the smokeyness and so I persevered. Generally, my driving is sub-3000rpm.
However, now, some 12 months and 5000 miles after that first start- up, I find that the compressions have improved to 190 on all cylinders bar No 4 which is 185 lbs/ft. The smokeyness now kicks in at about 3500 rpm. In all cases of hard acceleration there has been a cacophony of rattles from the engine at high revs coupled with the smokeyness. The noise is reminiscent of piston -slap - more a rattle than a knock. There is a puff of smoke on overrun after hard acceleration. the smoke is blue.
Everything looks fine. The oil keeps its colour. The temperature holds steady. It uses minimal oil if I keep it below 3000 rpm. The car is not my daily driver but I do use it for long pleasure drives. I wonder whether I should strip the engine before such things as pistons, rings become NLA. The insides of the bananas have an oily black deposit. Free-revving the car when stationary brings light smoke above about 4000 rpm and then more, briefly , on overrun. The problem was steadily getting better for quite a while but now it seems to have plateau-ed out. What is the consensus? Would you leave well alone or would you re-build the engine if you were in my position? Any comments gratefully received. TIA. Best wishes, John.
However, now, some 12 months and 5000 miles after that first start- up, I find that the compressions have improved to 190 on all cylinders bar No 4 which is 185 lbs/ft. The smokeyness now kicks in at about 3500 rpm. In all cases of hard acceleration there has been a cacophony of rattles from the engine at high revs coupled with the smokeyness. The noise is reminiscent of piston -slap - more a rattle than a knock. There is a puff of smoke on overrun after hard acceleration. the smoke is blue.
Everything looks fine. The oil keeps its colour. The temperature holds steady. It uses minimal oil if I keep it below 3000 rpm. The car is not my daily driver but I do use it for long pleasure drives. I wonder whether I should strip the engine before such things as pistons, rings become NLA. The insides of the bananas have an oily black deposit. Free-revving the car when stationary brings light smoke above about 4000 rpm and then more, briefly , on overrun. The problem was steadily getting better for quite a while but now it seems to have plateau-ed out. What is the consensus? Would you leave well alone or would you re-build the engine if you were in my position? Any comments gratefully received. TIA. Best wishes, John.
