To fine tune the timing, you do need a timing light. First, if you watch the video below, it shows one being installed in a larger engine. However, the procedure remains the same.
Here are the directions specific to your vehicle. The attached pics below correlate with the directions.
1998 Nissan-Datsun Sentra L4-1597cc 1.6L DOHC MFI (GA16DE)
Vehicle Powertrain Management Ignition System Distributor Service and Repair Procedures
For distributor removal and installation, refer to the following images.
Timing Mark For No.1 Cylinder TDC (Compression Stroke)
Hold down bolt torque: 16 - 19 ft. lbs.
I hope this helps. Let me know if you have other questions.
Take care and God Bless,
Images (Click to enlarge)
Saturday, March 13th, 2021 AT 10:03 PM