The differences between the F340e and S340e are optimized based on their application.  Specific changes were made so the S340e is configured to handle Stucco/EIFS applications better.  You will need to convert the F340e to an S340e using conversion kit 25A178.

Reference ToughTek™ S340e Portable Stucco Pump Operation, Repair and Parts manual 3A3437, ToughTek™ F340e Portable Fireproofing Pump Operation, Repair, and Parts manual 3A3109, and ToughTek™ S340e Pump Lower Conversion Kit Instructions manual 3A3439.

Read, understand and follow all instruction manuals and warning labels supplied with all equipment.  Only trained and qualified personnel should perform repairs on the equipment.