1966 LOTUS 41
Work performed: Our diagnosis is that the cylinders were "gas washed", meaning that the piston rings had lost their "bite" on the cylinder walls due to flooding the engine while trying to start it. The initial compression reading show this: Cylinder 1: 110 psi first reading, 116 psi second reading; Cylinder 2: 75 psi first reading/75 psi second reading; Cylinder 3: 85 psi first reading/88 psi second reading: Cylinder 4: 60 psi first reading/ 64 psi second reading.
When we performed a leak down test we found that air was escaping past rings and exiting through the 3 small holes in the oil sump vent cap. We believe that the carburetors are working as they should at this point in time and do not call for rebuild.
We performed oil change and filter. We were able to start and run the car 3 more times for a period of 10-15 minutes per time and we noticed that after we performed the later compression reading it drastically improved. This are the readings:
Compression check, cylinder 1: (front of engine/ facing forward): 200 psi; cylinder 2: 177 psi, cylinder 3: 172 psi, cylinder 4: 168 psi. Upon start up and running, oil pressure always maintained 40-70 psi on the car's oil pressure dash gauge.