Datsun 240Z Driveshaft – phased correctly?
By Thomas Walter
What, there was a MISSING bolt on the driveshaft flange. The remaining three were LOOSE, also a surprise. Obviously I had planned on replacing them, but had overlooked that task. The three odd bolts were removed, and replaced with correct items, bought long ago. The 5/16 x 24 tpi bolts, about 1″ long, installed. Replaced them all, using loctite (242 blue) in the process.
What… it was clear the drive line u-joints were 30 degrees out of phase!!! $%^&! Previous owner strikes again.
Removed the bolts, dropped out the rear half of the drive shaft (2000 only, 1600’s have one piece drive shafts). Cleaned the splines, lightly regreased them. Inserted the drive shaft, happy that the U-joints where lined up. Bolts back in… #$%^!!! I installed it 90 degrees out! Sigh, hot humid days in the garage are not fun. Removed the bolts a THIRD time, reinstalled the driveshaft again. Once again replaced the bolts, using a little locktite on them. Last, looked to make sure the u-joint yokes – closest to each other -were “in plane” with each other. If the U-joints are installed “out of plane” so those inner yokes are at different angles, it will cause a “whipping” motion of the drive shaft… usually the vibration is very noticeable. Not sure how I missed it, thankfully the u-joints and
differential bearing seem fine.
Drawing would be worth a 1000 words: Draw a line through the center of each u-joint and u-joint caps — the two resulting lines should be parrallel to each other