Monte72Carlo Posted October 12, 2010 Share Posted October 12, 2010 I was driving my car yesterday (fairly hard I must add). I know you probably wouldn't be able to come up with a diagnosis by me just explaining it but you may be able to point me in the general direction and whether or not it's serious. Anyways, it sounds kinda like a knock but not really a deep knock like a rod would make. It only happens when it's been driven for at least 10 minutes (it may be fully warm by then). It happens under low RPM and might happen under higher RPM but the exhaust is just too loud to hear over. It is most distinguishable under high idle. It sounds as if the pistons are coming in contact with the head or a valve perhaps? I can hear it on both sides of the engine and at the collectors. Or could it just be a valve lash problem? It has hydraulic lifters that I set myself (there is absolutely no way it could be a lifter problem, just throwing it out there). It doesn't really sound like the chatter of lifters. I really have no idea what it could be. All oils are sufficient, pressure is good. It defiantly sounds like an internal engine problem Thanks, Garrett. Quote Link to comment Share on other sites More sharing options...
kc8oye Posted October 12, 2010 Share Posted October 12, 2010 if it's more of a light tapping, you may have chewed up a cam lobe and got a lifter tapping away. I'd suggest you start by re-lashing the valves and see if it goes away. Quote Link to comment Share on other sites More sharing options...
Andy's Auto Posted October 12, 2010 Share Posted October 12, 2010 Garret, step one is check your torque converot bolts. When findind a noise, a "NO" answer is just as important as a "YES". That is how process of elimination is done. Andy Quote Link to comment Share on other sites More sharing options...
wallaby Posted October 12, 2010 Share Posted October 12, 2010 Converter bolts was my first guess too. Often times converter bolts will make noise at light loads, and tend to quiet when going uphill or under heavy loads. Like Andy said, determining what it ISN'T will lead you to what it is. Quote Link to comment Share on other sites More sharing options...
Monte72Carlo Posted October 13, 2010 Author Share Posted October 13, 2010 Alright guys, it's not the converter bolts. They are all nice and snug. I believe it's a bent push rod, I'm heading out to the shop right now to go and pull the valve cover. Thanks, Garrett. Quote Link to comment Share on other sites More sharing options...
MonteFox89 Posted October 13, 2010 Share Posted October 13, 2010 sounds similar to my problem since I've finally got the car running. I have asked around locally and they're saying that my oil may be to thin, it needs changed anyways so... yeah.... I'll double check torque converter bolts and.... yeah I'll pull the valve covers as well... Quote Link to comment Share on other sites More sharing options...
Monte72Carlo Posted October 13, 2010 Author Share Posted October 13, 2010 Well turns out all of my push rods are bent in some way, some worse than others. Is this normal? Must have really over reved her Quote Link to comment Share on other sites More sharing options...
Mike 57 Posted October 13, 2010 Share Posted October 13, 2010 How hard did you turn it? If you bent them all I suspect other issues. Quote Link to comment Share on other sites More sharing options...
AL M Posted October 13, 2010 Share Posted October 13, 2010 Did you drop a washer in your carb....lol, J/K. Quote Link to comment Share on other sites More sharing options...
kc8oye Posted October 13, 2010 Share Posted October 13, 2010 I took my basicly stock smallblock to 7200 rpm and didn't hurt anything.. i'd say you have issue.. Quote Link to comment Share on other sites More sharing options...
CrazyDavey Posted October 13, 2010 Share Posted October 13, 2010 Well turns out all of my push rods are bent in some way, some worse than others. Is this normal? Must have really over reved her Garrett the lifters will usually give up before it bends pushrods....did you re-adjust the valves after you fired it up the first time? Sounds like things might have been too tight to me.. Dave Quote Link to comment Share on other sites More sharing options...
Monte72Carlo Posted October 14, 2010 Author Share Posted October 14, 2010 Yea, It seems kind of odd to me as well. I had it up to 6500 a few times but not that many really. My engine builder set the valves with me before the engine went in the car, from what I know they don't need to be adjusted once it has been broken in. I do however have a much higher spring pressure and a large cam for stock push rods, maybe that's the issue? Anyways, new moly push rods on the way tomorrow and I can try my hand at setting valves.... I sure hope there are no other problems Thanks, Garrett. Quote Link to comment Share on other sites More sharing options...
kc8oye Posted October 14, 2010 Share Posted October 14, 2010 valves are pretty easy.. do 'em like the book says. I prefer to go back after the engine has been warmed up, and re-set them with the engine running. in my own personal experience, I've had much better luck getting them 'correct' that way. I've wiped out 3 valve trains trying to set them cold with the engine off.. somehow I managed to get it right on this engine... after I over rev'd it to 7200 it was acting funny.. took it home.. re-lashed the valves with it running, and it's been purring like a kitten since (also added a 6000 rpm rev limiter) I took an old chrome valve cover and cut the center out so I can get to the rocker nuts w/o it spraying oil EVERYHWERE.. :> Quote Link to comment Share on other sites More sharing options...
Monte72Carlo Posted October 16, 2010 Author Share Posted October 16, 2010 Alright, noise is still there. New push rods are in and no difference. The noise is still evident, if not worse. hmmmm Thanks, Garrett. Quote Link to comment Share on other sites More sharing options...
Mike 57 Posted October 16, 2010 Share Posted October 16, 2010 pull the oil filter cut it open and check for metal Quote Link to comment Share on other sites More sharing options...
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