Diagnosing Rebuilt Engine Tick?

Just rebuilt my 302.. new mains, rod bearings, crank polished, rings, pistons, gaskets but I left the cam, lifters and head because apparently cam had been replaced by previous owner and appeared in good shape. But anyways the engine fired right up, and ran good except for a tick ( not a knock ) coming from driver side valve cover area. I took cover off, and adjusted valves but no difference. I re torqued headers and inspected for possible leaks but couldnt find anything. I am suspecting a bad lifter but can anyone suggest anything to look for before I tear it down? Im a high school student and cant afford to misdiagnose it .. lol.

Also, it can be heard much better at idle or low rpm's.

Thanks,
 
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I believe the welds are fine , rpm seems to be slightly erratic ranging from 800 to 1100 ish Rpm's at idle.
Well that could be a few things in and of itself. Did you run codes? Check out the sticky on that. Lots of good info there. The ticking probably has nothing to do with the idle fluctuation. I've seen pin holes in welds on headers that have caused noise. When they thought it was a gasket. Probably a lifter-valvetrain noise but really hard to know:shrug:
 
Retorquing a header if it's leaking may not help it. Unfortunatley, once the gasket is blown, it's blown. Try unbolting the header, pulling the gasket out and inspecting it. If it seems fine, re-install with a thing bead of high heat copper silicone around each port. Torque from the inside out. Repeat this step a few times after the engine has cooled overnight. Headers should be torqued cold.

A worn lifter could also cause the tick you describe. Unless you replaced the lifters into the same lifter bores they came out of, in the same direction they were facing, you can't ensure that they aren't the issue.

I had a stupid one creep up on me. I swapped out my plug wires a couple of months back while shooting the bull and having a beer with some buddies. Since I was only half paying attention to what I was doing, I neglected to ensure one of my rear plug wires was on. The engine developed a tick in the top end. Since I have a fairly healthy cam, I didn't notice the miss. Put the plug wire back on and it disappeared.
 
Just rebuilt my 302.. new mains, rod bearings, crank polished, rings, pistons, gaskets but I left the cam, lifters and head because apparently cam had been replaced by previous owner and appeared in good shape. But anyways the engine fired right up, and ran good except for a tick ( not a knock ) coming from driver side valve cover area. I took cover off, and adjusted valves but no difference. I re torqued headers and inspected for possible leaks but couldnt find anything. I am suspecting a bad lifter but can anyone suggest anything to look for before I tear it down? Im a high school student and cant afford to misdiagnose it .. lol.

Also, it can be heard much better at idle or low rpm's.

Thanks,
Have you found the cause yet?
 
I just pulled the upper and lower intake manifold off and checked out the lifters. What exactly should I be looking for ? They were no stuck lifters, and no play In the rockers. I haven't tried that header sealant idea but that will be my next move. I can get lifters at a good price on sale at AutoZone ending on Monday so if I gotta get a set I need to get them soon. Thanks a lot guys
 
I just pulled the upper and lower intake manifold off and checked out the lifters. What exactly should I be looking for ? They were no stuck lifters, and no play In the rockers. I haven't tried that header sealant idea but that will be my next move. I can get lifters at a good price on sale at AutoZone ending on Monday so if I gotta get a set I need to get them soon. Thanks a lot guys
Personally I'd just buy some new ones. Adj everything and seal up the exhaust. Are you reusing the valvetrain from before you rebuilt? Pushrods the right length etc? Also I remember a member on stangnet had a ticking which later discovered it was a bad spark plug wire that was arcing
 
Okay im going to go ahead and just buy a new set to be safe. But yeah there was no tick before the rebuild and I re used the pushrods and the heads which were recently rebuilt. I'll also pick up some of that exhaust sealant and seal it up. I checked all of the plug wires several times and I believe they are good. I can hear the sound best in the cylinder 5,6 area. So maybe I didn't install something the way it came out on that side. I'll let you know if I find anything. Thanks a lot
 
Personally I'd just buy some new ones. Adj everything and seal up the exhaust. Are you reusing the valvetrain from before you rebuilt? Pushrods the right length etc? Also I remember a member on stangnet had a ticking which later discovered it was a bad spark plug wire that was arcing

Okay, I went in and installed new lifters , and I soaked them as well. I also tried to seal up the exhaust as best as I could. But sadly no luck. Still a tapping, clanking noise coming from the same area. I was thinking it could be a piston to valve clearance issue but the exact same size of pistons were used so that can't be it. What do you think ?
 
Did you change valve covers when you rebuilt the engine? With some covers there are clearance issues with the baffles. You previously said the noise was more noticeable at idle. Is that still the case? Does it get "faster" with rpm increase or louder? Are you sure the pushrods are straight on reassembly?
 
Did you change valve covers when you rebuilt the engine? With some covers there are clearance issues with the baffles. You previously said the noise was more noticeable at idle. Is that still the case? Does it get "faster" with rpm increase or louder? Are you sure the pushrods are straight on reassembly?
No I left the valve covers, only thing I did was paint them and install a new gasket. But it wasnt making this noise before I rebuilt it. But it's more like a clanking noise the more I listen to it. It sounds like it's right under the valve cover, but the pushrods are straight I checked them. It does increase with rpm but fades away some at about 1,500rpm. It sounds like it's missing but the engine feels like it has full power and doesn't shake. It's really weird.
 
Last night it was getting very bad I though it was about to through a rod it was so loud, but it wasn't really a knock. I revved it a few times and one hard time and all of the sudden it stopped. It's still slightly audible but barely at all. It pretty much completely went away.
Weird?!? Oil pressure is still good? No smoking or anything? Maybe you had an exhaust leak that needed to have a few heat cycles to seal. Really hard to say anything without being there. Also I'd change the oil filter and cut it in half to check and see there isn't any access metal wear. You could of had a small "something" that was dropped on top of the piston that got "blown" out the exhaust when you revved it. But if it was that loud I'd expect at least that would hurt a valve
 
Weird?!? Oil pressure is still good? No smoking or anything? Maybe you had an exhaust leak that needed to have a few heat cycles to seal. Really hard to say anything without being there. Also I'd change the oil filter and cut it in half to check and see there isn't any access metal wear. You could of had a small "something" that was dropped on top of the piston that got "blown" out the exhaust when you revved it. But if it was that loud I'd expect at least that would hurt a valve

I had great oil pressure the whole time , it has never dropped. But I do honestly think it has to be related to the lifters not having enough oil for some reason. Like all of the sudden they got enough oil pressure to stay pumped up and not make a clacking noise. It sort of comes and goes but I'm gonna let it go through several heat cycles and maybe a valve adjustment when I get home from school. It has a bad exhaust tick now when accelerating so that probably has something to do with the headers.