I've had a ticking noise coming from the engine ever since I installed a larger cam and headers. I was thinking it may be an exhaust leak but have not been able to find one. I pulled the heads because I've had white smoke coming from the exhaust and thought it was a bad head gasket but both were fine. I'm having the heads inspected by a machine shop to make sure there aren't any issues.

Below is my video with the ticking sound as well as showing how much play the pistons have. Is this much movement normal or do I need new rings? I'm wondering if bad rings would cause the white smoke and the ticking noise, even though I thought white smoke was usually coolant, not oil.

Any input is appreciated as I've been trying to track down the cause of these issues for a while. I don't want to pull the engine unless I have to. Main mods are FTI Streetsweeper HT cam, XSPower headers, dual valve springs, rocker trunions, push rods, and lifters. Car is a 2002 with 97k miles.

 

White smoke to me also meant coolant and your pistons look like they been getting doused the rust is showing! I would guess your in for a entire lower end rebuild! Good look. It’s the time build a stroker !

 

GM was replacing pistons back in 02 for tapping noise. Sometimes it was caused by carbon build up on pistons. Oil economy? I couldn't hear the tapping over the other noises. Piston wiggle isn't uncommon.
White smoke is water/coolant piston of effected cylinder would be clean of carbon. Exhaust port of effected would also be clean. Aluminum heads can crack and with no indication until the head heats up.

 

headers do not dampen valve train noise like cast exhaust manifolds do. The noise you hear may be normal

 

I know there’s some increased noise with the stiffer valve springs and headers and typically that’s what I hear. Occasionally though there’s really loud ticking that comes when the engine is warmed up. It’s not predictable and comes and goes. It’s a very loud tick and does not sound the same as the usual valvetrain noise. I thought it was a lifter and replaced them all but that didn’t fix it. The sound in the video was poor quality and you can’t really hear it. My main question is whether or not I need to replace the piston rings. I’m leaning towards pulling the engine and replacing them just in case they’re bad. There’s probably a gasket or two that need to be replaced anyways.

 

Rocker arms and trunnions get worn ! And make noises!

 

That movement doesn't really look excessive and the pistons are not covered in rust. I'm doubting excess piston to cylinder clearance would cause an intermittent loud ticking/knocking noise. Changing just the rings doesn't change the piston to cylinder clearance. I would look more closely at all the valve train components.

 

Do the head bolts enter the water jacket? Could be weren't doused with enough thread sealer last time installed since gasket looked good. Did you check engine running with a good vacuum guage? I have no idea about acceptable piston movement. Is clicking noise once or twice with a spark plug strobe light blink? Leak down test for hissing from exhaust pipe before head removal (weak rings)? You know, the fuel injectors can tick loudly at times.

 

The rocker arm trunions are new but I'm getting the machine shop to look over those too. And yes that's not rust it's buildup from running rich. Not sure if it's from the tune or something else but I'm looking into it (possibly a bad MAF, O2 sensor, injector...). I've decided I'm going to pull the engine since I know one or more of the gaskets are leaking. I'm planning to replace all the gaskets as well as the rings since I have the engine out. That will be one less thing to look at too if the ticking noise is still there. I coated the head bolts with a good bit of sealer and they were all snug so don't think coolant was getting through. I didn't do a leak down test before pulling the heads but I guess it doesn't matter now since I'm replacing the rings. I also checked the cylinder walls and don't see any scoring. It's hard to tell how often the ticking is happening per spark plug fire but it doesn't sound like it's happening in all cylinders. Is there a good way to test for a bad injector? It probably wouldn't hurt to run so injector cleaner through them.

 

I would say there’s indications where Clearly coolant was seeping in your n.1 ,n.3 piston! Also the car was running a tad rich. But whether the problem started at the gasket which is more likely. Diluted fuel doesn’t burn well if at all! If you want my advice continue on since you already in it for the long haul. Updates/Upgrades to the lower end forged std pistons forged crank should be done for stability purposes on my opinion! Rather then dabble on about it . Look up the LSA crank ! It’s forged! with 2 types of metal! Slapping on a set of forged heat treat push rods wouldn’t be a bad idea either! And while your hooking it all back up! Throw your stock coil packs in the old boxes that new high out put coils would come in you will no longer suffer a detonation issue! Or power loss! Bigger alt ! Change the water pump and seals/ thermostat! Your injectors can be reused if you clean them. Me I rather buy new ones! 60’s should treat you nice since they can run at the same psi as your fuel pump! Let’s not forget led lights again saves you ! If if your gonna tackle it do it all right the 1st time around. It may be years and years down the road before you had to do anything other then change the oil! Do what you will though I just suggest it might save you a lot of further headaches the time building and waiting is worth while. Especially if you got ideas for a new cam or such as well make some real ponies from that motor!

 

Does the noise go away when the OIL Temperature reaches the 110 to 120 range? The LS engines typically have some piston slap until the engine oil gets up to temperature. Both my 97 and 03Z would slap some when the engine was first started for the day. On cold track day mornings at Watkins Glen you could always hear several C5s knocking away in the garage while the engines were warmed up before heading out on track for the day. Here is a video I made back in 2011 of a buddy's C5Z rattling away in the garage at the Glen. My 97 and 03Z sounded exactly like this on every cold start.
Bill

 

That noise sounds similar to what I hear sometimes but the louder ticking noise I hear doesn't happen until the engine is warmed up which led me away from thinking it's piston slap. It comes and goes and is louder than the usual valvetrain chatter I hear.

 

Hmm switching to a 6.125 ls forged rod and a different forged piston at -2 to -3cc would be a great option for a std bore should reduced piston movement or slap in this case to a near 0 good luck !

Im planning on running a 3.905 @-8 or -15cc with the forged 6.125 rod from my readings it’s a near perfect upgrade.


You might want to check your plugs for gapping and over tightening . They should be really no more then a little over hand tight one little torque on the wrench just enough to snug um in there not crank them down it’s a big no no!