Lifter Preload

[MOPARJ]

My 318 has an XE268 and comp lifters, with the rest being stock stamped steel rockers, shafts, and pushrods.

It has a slight tick at engine speeds above idle, but nothing severe. Just a light tick. Great oil pressure and lots of oil to the valvetrain. I am assuming that it is just the Comp XE lifter ticking, due to the fast ramp rate, but just to be sure.....

How does one measure the lifter preload properly on a setup like this? And is it even needed in minor situations like mine.

Other than a collapsed lifter 3000 miles into the rebuild of the motor, it was replaced and the motor has gone an addtional 12000 miles trouble free and strong.

It gets warm in Cali sometimes, so I run 20w50 VR1 oil for the extra zinc. Oil pressure at idle at its warmest temp does not drop below 30 pounds ever.

 

[Snake]

yep dam comp cams.I have the 280-h and it ticks,everyone here says we need different push rods and adjustable rocker arms,I think its crap that we have to go through this.On outher forums they say its normal because of the fast ramp live with it or go the outher route being spend more money.

 

[6dart9]

How does one measure the lifter preload properly on a setup like this? And is it even needed in minor situations like mine.

I went through this when building my engine and in the Mopar Engine Manual being it is hyd the pre load is adjusted on the lifter because it (the lifter) compresses / decompresses. I will look up the exact wording and put it in here. But i basically found out you dont have to do anything in terms of pre loar on the rocker shafts.

hope this helps

 

[moper]

This should be an assembly step for any performance build, kind of like lifter to bore clearance and lifter rotation. To check preload, you have to have the intake off, but the rest of the engine together and a set of feeler gages. Wirge gages are best if you can find them. I simply set #1 in TDC of the compression stroke, and start with the #1 lifters, then turn 90°, do #8, etc.. following the firing order. You measure the amount of distance between the bottom of each lifter's plunger retaining clip and the top of the plunger. With shafts and non-adjustable rockers this is critical to keep things together and quiet. Because if you need to adjust it, you have to buy pushrods. Things that can affect the preload are gasket, valve job, milling on the block and/or head surfaces, lifter bore clearance, camshaft manufacturer, pushrod length, and rocker/shaft manufacturer... and of course wear on any of those parts. So if any of that get's altered or worn, you should check preload.

 

[Snake]

well exsplained me got it now.