I have a 302 that had some noisy lifters and when I pulled the valve covers it seemed some of the rocker arms rocked a little loosely...so I tweaked'em down a tad (really not much...maybe 1/8 turn o n most) aftrer that it seems to be down a bit on power and popping back just a touch and generally just not running quite right. So my conclusion is that it must have solid lifters...which I havenever had,so I am going to readjust the valves.....what should I set them at?
I dont think you do have solids. I you tweaked some tighter with the motor not running, you may have overtightened some. To set the lifters correctly, warm up the motor, then at the slowest idle you can make it run, (so as to not spray oil all over), remove one rocker cover at a time. With the motor running, loosen each rocker nut untill it just starts to click, then tighten 1/4 turn and go to the next. The reason some seemed loose with the motor not running is because those were at the base of the cam, while others were not. To find the lash for a solid lifter cam, you need to get a number off the cam, then call the manufacturer.
302 Ford or 302 Chevy?? Anyhow...try pushing down on one of the rocker arms right above the pushrod (with the engine OFF ofcourse...I shouldn't have to say that, but you never know! Ha Ha!) If the lifter plunger compresses at all, it has hydraulic lifters. A loose rocker arm can be caused by a bent pushrod, a collapsed lifter, a stuck valve, a broken valve spring and a broken rocker arm fulcrum...it doesn't neccessarily mean you have solid lifters. Also, engines equipped with solid lift cams tend to have pushrod guide plates installed, so that provides another visual clue. If tightening the one loose one down affected engine performance with popping back and such, it may be holding a valve open. Check for mechanical damage in the areas I mentioned above. Valve lash settings for mechanical (solid) lifter cams generally fall into a 'range' of what the manufacturer feels is acceptable, and can be different from one cam grinder to another. It's best to know what you have, and then look up specs for that given cam number. Check it out and see if you indeed do have a solid lifter cam. It's a good bet you have a hydraulic cam with an issue on one valve.
that makes sense...I really thought 1/8 turn should have been a small enough amount thet the hydraulic lifters would have compensated for it? So maybe it is just one a little overtight. As for adjusting the valves with it not running,I thought you were supposed to adjust them at the base of the cam?
are the rockers or pushrods adjustable? thats another good clue that you may have solid lifters. If there is no adjustability, its about certain you have hydraulics. on a hyrdo lifter, you should feel some compression when you press on em. -scott noteboom
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