[LSX Freak]

Got my car last week and drove it pretty much all week before I had to leave town. It's been sitting for a better part of 3 or 4 years, being driven minimally. I noticed when I picked it up there was some valvetrain clatter. (Yeah I probably should have taken the time to adjust it but didn't really have time to dive in real deep on the car since I had been gone 2 months, home for a week, and out of town until who knows when.) I noticed at about 5300 rpm according to the factory tach it will get a pretty noticeable knock on the passenger side (sounds like anyway) but then go away at about 5500. I figure it was just something out of wack in the valvetrain so i just quit revving it that hard. No knock when it returns to idle, and gauges look fine during and after it. The more I got to thinking the more i realized the only other 2 engines i heard with a high rpm knock like that needed a cam. I'd like to bring the car down to Alabama but won't if it does indeed need a cam. My next thing is, I don't want to throw a cam in it to enjoy it for the summer just to tear it back apart this winter to put a bigger one in it when I plan on doing my winter mods, nor will I have time to. HELP!!!

[fogged306]

Do you have a dial indicator and base?

And is it definitely a knock, or more of a tick? A knock usually means rod bearings.

[93hatch]

did you say cam went bad wat

[LSX Freak]

Originally Posted by fogged306 Do you have a dial indicator and base? And is it definitely a knock, or more of a tick? A knock usually means rod bearings.

I would consider it a knock tbh. It never loses oil pressure or anything though. Isn't that the first sign of a bearing cashing in? I'm new to this whole troubleshoot and actual diagnostics thing. In the old trucks we used to run you'd just run it until it wouldn't turn over and go buy another scrapyard 350 for $200.

[fogged306]

If you are going by the stock gauges, you can't really be sure of anything. They're not very accurate. I've also seen engines with 10lbs at idle run for years. I've had one myself that would idle under 15lbs when it was warm and it ran until I sold it like that and I never had an issue. If you have 0 lbs, then yes, definite sign of main bearing failure. Can't say I've ever had a rod bearing go and checked the oil pressure though. Rod knock is a very definitive sound and once I hear it I know exactly what's wrong. If you've heard it once, you'll know exactly what it is every time you hear it after. Piston slap does sound very similar, but you usually get that on a cold engine.

Easy way to check is to pull your oil filter and cut it open. Bad bearings will look like gold flakes in the filter pleats and around the casing of the filter.

[LSX Freak]

Originally Posted by fogged306 If you are going by the stock gauges, you can't really be sure of anything. They're not very accurate. I've also seen engines with 10lbs at idle run for years. I've had one myself that would idle under 15lbs when it was warm and it ran until I sold it like that and I never had an issue. If you have 0 lbs, then yes, definite sign of main bearing failure. Can't say I've ever had a rod bearing go and checked the oil pressure though. Rod knock is a very definitive sound and once I hear it I know exactly what's wrong. If you've heard it once, you'll know exactly what it is every time you hear it after. Piston slap does sound very similar, but you usually get that on a cold engine. Easy way to check is to pull your oil filter and cut it open. Bad bearings will look like gold flakes in the filter pleats and around the casing of the filter.

I figured if it were something that serious it'd knock all the time. Detonation? I'm just throwing ideas out now so I can sleep at night hoping I'm not going to sink a ton of cash in an engine I don't plan on keeping in the car.

[fogged306]

Detonation will sound more like marbles in a can than a knock. Kind of tough to diagnose without actually being there ya know. Any mechanic should be able to listen to it and give you an idea of what you have going on. Short of pulling the valve covers and taking a look and checking the torque on all your rockers, and checking your oil filter, I couldn't really give you much else to look for.

[LSX Freak]

Originally Posted by fogged306 Detonation will sound more like marbles in a can than a knock. Kind of tough to diagnose without actually being there ya know. Any mechanic should be able to listen to it and give you an idea of what you have going on. Short of pulling the valve covers and taking a look and checking the torque on all your rockers, and checking your oil filter, I couldn't really give you much else to look for.

Yeah, that's the only pain about it is its impossible for anyone to really see what I'm talking about. Thanks for at least finding somewhere for me to start with the oil filter thing. It'll be a while before I can get home to check things out, but I'll definitely keep this in mind and pray against the worse.

[LSX Freak]

Originally Posted by fogged306 Detonation will sound more like marbles in a can than a knock. Kind of tough to diagnose without actually being there ya know. Any mechanic should be able to listen to it and give you an idea of what you have going on. Short of pulling the valve covers and taking a look and checking the torque on all your rockers, and checking your oil filter, I couldn't really give you much else to look for.

Yeah, that's the only pain about it is its impossible for anyone to really see what I'm talking about. Thanks for at least finding somewhere for me to start with the oil filter thing. It'll be a while before I can get home to check things out, but I'll definitely keep this in mind and pray against the worse.

[fogged306]

Worst case, you can find a shortblock on craigslist or the junkyard for less than $300 to slap in until you do something different.

[LSX Freak]

Originally Posted by fogged306 Worst case, you can find a shortblock on craigslist or the junkyard for less than $300 to slap in until you do something different.

That's what sucks, the block doesn't have but about 20k miles on it. Block was brand new with the rebuild. I guess if worse came to worse I could, but I may just run the piss out of it until winter anyway.

[01V8MUSTANG]

Just throw an LS series motor in it and be done!

[LSX Freak]

Originally Posted by 01V8MUSTANG Just throw an LS series motor in it and be done!

Not quite prepared to go that route yet.... That's my final plan though.

[LSX Freak]

Originally Posted by 93hatch did you say cam went bad wat

Was looking back over something and realized i didnt see this post

Yeah I said cam went bad, youve never seen a rounded off lobe?

[93hatch]

never seen it happen in a hydralic roller

[LSX Freak]

Originally Posted by 93hatch never seen it happen in a hydralic roller

Didn't realize these were hydraulic roller motors. Guess the odds are pretty slim then?

[93hatch]

very

[LSX Freak]

Originally Posted by 93hatch very

Ah geez fuck. It just doesnt sound like something in the bottom end. Maybe ill pray for a bad lifter now

[93hatch]

Ive heard bone stock foxes ping and have valve float

[LSX Freak]

Originally Posted by 93hatch Ive heard bone stock foxes ping and have valve float

Stock heads that have been worked and a pretty small cam. Maybe that's the culprit. My brother said it sounded like a floating valve as well, but it never really quits pulling.