OK, i deleted my other post to be more specific with this... Thought i had some valve or other damage... but no. Here's a little background: Engine stalled, then turned over for about 45 seconds before it would start (due to an ignition problem that i already knew about). In that 45 seconds of turning over, the oil pressure was sorta low, i think. When the car started, it jumped in RPM to like 3500, then had a steady backfire through the carb. Got it home, pulled the valve cover, and noticed TWO pushrods (from different cylinders, 1 intake, 1 exhaust) were off their lifters. Just sitting there, hanging out. Not bent, no damage... just sitting there. SOOOOO... im thinking... could the hydraulic lifters been bottomed out due to the low oil pressure, allowing the pushrod to be thrown with that sudden jump in RPM (and little oil)? I put it all back together, but one lifter seems bottomed out. Not going to start the motor until this is sorted... Im aware that lifters can go bad... but unaware as to exactly what goes bad about them. Ive replace lifters that were sticky, and such... but have never seen one just bottomed out. Is that lifter BAD? should i just pull it apart and clean it? (um... not sure they come apart, do they?) Or should I just replace it? Or will it be fine just putting it back together and letting it pump up? take it out and bleed it? The engine is a '70 dodge 383, stock grind cam for a '68, stock mopar lifters, stock rockers... The motor is in my '55 plymouth... my daily driver, which has been treating me like most women in my life have... tempermental, lots of "the silent treatment... so i KNOW it's a "she" now...
you might have a couple of flat lobes on your cam.do you have adjustable rockers? i'm not a mopar guy really,but maybe they loosened up somehow?
well... just to check it out... setup my dial indicator, and turned the motor over... measuring each lobe. All within reasonable tolorance of each other, and nowhere near flat. This cam has maybe 1200 miles on it, so i'd be really worried if it were flat... Dropped in a known good set of lifters (although not used with THIS cam, before... the surfaces were polished before going in). Luckily it took maybe 30 minutes to swap out the lifters and put everything back together (didnt have to pull the manifold). Did a quick compression check, just to make sure all is good... and fired it up. Runs good. Would still love to know how the heck this happened in the first place, though.... Tomorrow the new mopar perfomance electronic ignition goes in, as well as an electric fuel pump (curing 2/3 of the car's issues). Pull the trans next week to replace one silly little seal... Then if i can just keep the car in one piece, it'll be great!
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