Thread: Bottom end, or valve?

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Hey there. I was playing around with my 86 Camaro (4BBL 350, 700R4). I fixed this horrible exhaust leak, and now my car sounds great, except for a tick I'm hearing.

I couldn't hear the tick previously (Yea, the leak was pretty bad. Upon jacking it up, two exhaust manifold bolts fell to the ground.) but now that all my exhaust is exiting through the pipes, it's showing up pretty good.

The tick is apparently coming from the drivers side, it's rather high pitched, although not as high pitches as say an exhaust leak. Sounds about like tapping a penny against a wooden surface. The tick matches RPM, and is much more apparent when decelerating using compression (as opposed to brakes) and when idleing at a stop sign. If I pull up to a red light, and there is a car next to me, I can hear it echoing quite loudly. I know what a broken piston sounds like from my Nova's old 305 (Thanks, nitrous ), and it sounds a bit different.

The motor idles very smoothly, but shudders a bit on acceleration when out of gear. If I am in park, and bring it up to about 2400-2600RPM, the tick is quite loud, and there is a rather strong vibration.

Do you think this is perhaps a valve problem? Pushrod/lifter? Or does it sound like more of a bottom end problem?

Any advice on how to better diagnose this?

Thanks in advance, folks

Upon further inspection, I found where the tick is coming from. I open the hood at idle while it was ticking badly, and couldnt quite place it. Laying down next to the car, the noise sounded like it was coming from either the back of the oil pan, or the torque converter. There isn't a TC cover on right now, and it sounded like the tick was coming at me from the flexplate to TC. Hard to tell though. I need to pick up a stethoscope to tell which is emitting the noise..

The tranny vibrates rather badly in 3rd.. Hmmm.

check the converter bolts, may be loose or missing.and while your there you could check that the trans is tight too.

Originally Posted by WRENCHD

check the converter bolts, may be loose or missing.and while your there you could check that the trans is tight too.

have had this happen this is were i would look first i use thread locker on the bolts and no lock washer they can crack out

Cracked flex plate.