Guest dvlax28 Posted December 23, 2003 Share Posted December 23, 2003 hey i just got my 240z back running. the problem i have now is that after adjusting to the specifications of .010" intake and .012" exhaust, when it runs it just seems a little rattly. kind of like a sewing machine. i adjusted them while it was hot, havent tried checking what they look like cold. i am wondering if the sound means that they are a little loose, because tightening them would not be a problem. its a p79 head on a f54 block 280zx L28 in my '73 240z. anyone know if the sewing machine "ticking" sound means too loose, or too tight? thanks, and any other help would be appreciated. Jason Quote Link to comment Share on other sites More sharing options...
JMortensen Posted December 24, 2003 Share Posted December 24, 2003 Are you good at adjusting valves on an L series? If not, by the time you got to the last one it was probably cold enough to throw your gaps off. Also, many aftermarket cams have different specs for lash. Mine is .006 and .008 hot. I've also seen .008 and .010. Maybe do an adjustment cold to .008 and .010 if it took you a while to get through it. The Snap-On crows foot tool for L series motors is pretty handy too, if you can stomach the price... Jon Quote Link to comment Share on other sites More sharing options...
Guest dvlax28 Posted December 24, 2003 Share Posted December 24, 2003 yeah i probably have an aftermarket deal, and yes the engine was still hot after checking/adjusting them, never cooled down. im just gonna adjust them a little bit tighter, cuz it sounds a little too rattly. Quote Link to comment Share on other sites More sharing options...
spotfitz Posted December 24, 2003 Share Posted December 24, 2003 I would try to find out if indeed you have an aftermarket cam, as mentioned. You could also reverse the order you adjusted them the first time. Meaning if you start from the front and worked your way back, now start from the back and work your way forward by rotating the crank the other direction. Should take care of the problem of it cooling down, if slow at adjusting. You can also adjust 4 at one turn of the crank to speed up the process. The lobe doesn't have to be exactly straight up for an accurate adjustment. As long as the rocker isn't on the "ramp" of the lobe, the base circle is the same. It's alittle harder to keep track of which ones you've done though. Hope this helps. Quote Link to comment Share on other sites More sharing options...
fl327 Posted December 24, 2003 Share Posted December 24, 2003 Took me a while to get the hang of it too. I used to have to do a cold adjustment, then warm up the car and adjust it again. After your third or so try, you should have that sucker humming, and not rattling. Quote Link to comment Share on other sites More sharing options...
Guest dvlax28 Posted December 24, 2003 Share Posted December 24, 2003 alright i'll probably tighten them up a little today, after i put in my new bushings, i swear every bushing was destroyed under the car. thanks Quote Link to comment Share on other sites More sharing options...
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