LIFTER PLUNGER TRAVEL THE EASY WAY
Different brands of hydraulic lifters can have varying travel. Here’s how to measure plunger travel easily. We use a short length of pushrod chucked in our drill press, and a block of soft wood, to not mar the lifter face or roller. Take the slack out of the pushrod to plunger, lock the spindle, set a razorblade on the top of the lifter, against the pushrod, and turn the couch by hand until you have a good line around it. Blackening the rod with a sharpie first makes the line easier to see or use a blued pushrod. Next, using the drill press as an arbor press, and with a steady down pressure, compress the plunger and wait until oil stops flowing from the side port. Pump it a few times until all the oil is released. Now bottom out the plunger and lock the spindle again, and mark as before. With the oil cavity empty, you can take your time running a pattern on the valve tip without worrying whether the plunger has moved or using light checking springs. We bolt the finished head to the block before we collapse the lifter, and it doesn’t need to come back off. Subtract the plunger travel from the checking pushrod length and add .025 to .050 for desired preload.
Timm Jurincie
Tuf-Enuf Performance
Avondale, AZ
Jan, 2023
