I have a 82 Camaro 305 with 3 speed AT. I am getting this knocking sound. It sounds like it is coming from the block. Sound is loudest at about 2000 rpm. On the highway the engine/power cuts out then kicks in kinda like a frozen gas line might.(It gets real cold up here in winter)

I will be dropping a new crate engine into this girl in the future so just want to keep it running now.

What do you guys think is causing this knock?
Thanks
Greg

 

Greg,

Welcome Aboard!

That kncking sound could be anything from a loose flywheel torque converter to a failing rod or main bearing. Make sure the engine oil is clean, full, and has adequate viscosity. 0W-X or 5W-X mineral oils are not very good at protecting an engine at higher temperatures (like when the engine warms up). If you really feel you need to use low viscosity engine oil, change it very frequently, limit the the engine load and speed, or change to synthetic 10W-X. The 10W-X synthetic has better cold flow and lubrication than even 0W mieral oil, and protects a lot better at higher temperatures and loads.

Be sure you have adequate oil pressure and a clean filter. Low oil pressure will almost always result in a bearing clearance knocking noise, and will usually be accompanied by lifter noise.

Another possibility is a loose harmonic damper ring or hub. Check the crankshaft bolt for tightness, and inspect the outer ring of the harmonic damper for looseness.

If you have the facilities, raise the vehicle and place it on stands. Remove the flywheel inspection cover and check the torque converter mounting bolts. Try moving the crankshaft fore and aft to check for excessive play. While you're there, make sure the transmission bolts are secure and the driveshaft and universal joints are not loose.

ASide from that, you may have little recourse but to open the engine for inspection. Since you plan to change to a different engine in the future, you may want to start shopping now while you nurse the old engine along as long as possible.

Good luck.

 

Another one I have seen is the timing chain worn so much that it hits the timing chain cover. Not real hard to change but not the easiest job either. Anyway you might want to check for it.

 

Just had that happen. There was a strange ratteling noise that popped up. I pressure washed my motor and the next day I had a steady drip of oil from the front so I figured I washed out my "gunk" seal from the fonst seal. When I pulled my Timing chain cover I discovered about half of the nylon teath gone off of the cam gear and a worn thru spot on the timing chain cover. After all was replaced the strange ratteling noise was gone and now I only leak 1/2 a qt of oil every 2k miles.

 

Hey you sound like the same knock I get when I used to start mine. I think your is a little more advanced mine never cut outon me but I have a simple thing you can try if you want. Go to a chevy dealership and get carbon cleaner....I think some of the guys could help you finding it, a frined got it for me...my car knocked. You put this stuff in your carb while its running and man does it smoke and cleans off your pistons and makes the knock in my car go away..I think this could be a bit too simple but hey give it a wirl this stuff isn't expensive and it won't hurt