Quote Originally Posted by DennyW View Post
Guys, listen. The adjustments for these is all over the place. 1/2 turn is fine, how ever. The whole point of the adjustment is to put the lifter plunger in the center of the total travel, and not have the plunger come up and hit the plunger retainer. So, if you adjust them to light, you could pop the retainer out, and the plunger come up out of there, and possibly push a valve into your piston. To tight, and you put excessive load on the cam lobs. It is a hydraulic cushion, thats all. The basic adjustment is 3/4-1 turn. If the lifters won't adjust properly, change them.

PS: If you run high oil pressure, or a high volume oil pump, it's always a good idea to install Anti-Pumpup Lifters. Why ? At higher oil pressure, at high rpm's, it will actually over pump the lifter because of the bleed down rate of the lifter. This in turn, will pump up the lifter opening the valve more than normal. Also known as valve float.
Just trying to help.
After doing a piston ring installation, one exhaust valve on my pushrod hydraulic tappet 2 cylinder Polaris RZR 800 engine is not closing, as evidenced by a rough idle,carbon on the valve seat, and a cylinder compression of only 80 lbs (the other cylinder is 110 lbs).I've disassembled the top again and installed new rings on both cylinders. I've disassembled all four lifters and cleaned them, put in new oil in the plungers. Now, when I tighten down the rocker arm bolts to the recommended 22 ft/lbs, all the valves push open about an 1/8th inch. There is no adjustment on these rocker arm holders, just one center bolt tightened to 22 ft/lbs. Will these tappets pump down and allow the valves to close when I start the engine? Might a piston hit a valve and do damage? Should I remove the lifters and remove the oil and let them pump up on their own? Ah man! I surely liked the solid lifters and adjustment bolts on my chev 348.