The previous 18O4+/8+ run to TUDA-II finished midday yesterday. OLIS was prepared for 17O delivery from the Supernanogan source. Leak checking was done last night. The big offender was a failing metal seal on IOS:TP7. The pump will have to be replaced. Meanwhile the pressure is sufficient for 20nA of 17O3+ with 2.5mm (middle selection) apertures inserted. Present agreement is to leave TP7 as-is for this run.