Loud tick/tap after warmed up
 

Ok for those that haven't seen the build thread here it is just to get an idea of what was done

http://www.njfboa.org/forums/showthread.php?t=61831

Otherwise its PRC stage 2.5 5.3 heads
ls7 lifter
hardened 7.4" pushrods (measure 7.3875 @ .050" preload)
Comp cams trunion upgraded rockers
.675" Dual valve springs

Loud tick, car misfiring, NO CEL. Noise sounds as if it is on the driver side.

But started happening the week after the engine swap was finished. At first I thought maybe it was just an exhaust leak and ended up finding a crack in one of the collectors on the driver side head. Welded that up best I could and noise was gone at idle, started driving home and after it warmed up and had a load on it started tapping again. Same noise and no difference in volume

When I finally got off the highway it started stumbling a little. So I decided to recheck my valvetrain (torque on rockers, pushro length, collapsed lifter, springs)
Ended up finding a broken valve spring, one of the new ones that just went it. Thought that has to be it. Got the new spring installed and double checked pushrod length with the comp cams tool. With .050" preload I came up with a 7.3875 pushro so the 7.4 was good and put me at a preload of .063". Retorqued everything and started it up. Again noise is gone alowed it to idle to operating temp., no issues. Drove the car and 5 minutes into driving started tapping and missing again. (broken spring was on the passenger side 5th spring back)


Got to my buddies house and pulled the valve covers again thinking has to be another broken spring. Didn't find anything!!!! Cranked it with the vavle covers off watching the springs and valvetrain. Didn't see anything extraordinary. Put it back together. Noise was gone untill started driving again.

I don't have any check engine light. Vehicle does misfire when it does it but I can't monitor individual cylinders with my scanner to see where it is coming from, I tried pulling plug wires see if I can here the engine acoustics change but it doesn't go away and just arcs to the coil bracket.

I didn't see any other arcing going on or any signs or arcing

Think that covers everything I checked/did, may have forgotten something.....

Next step is gonna borrow NJ Mike's coils and get new wires and see if it goes away. With the heat and load it sound like a coil is failing, just wish I can see the arc if that is what the ticking is

I have a sound clip I have to try and upload.

Any suggestions, or experience with coils failing like this(if thats whats going) please chime in

well to give you guys an update. I swapped could and wires on all 8. Noise is still there once it gets hot.

Only thing I can think of is maybe a bad lifter.......

I'm at a lose, not sure if I should try plugs first or what

lifter to me. should only take about 30 min to pull the driver side head.

Thanks for the input, that's what im leaning towards myself now, I guess I was just hoping it was a coil.

Just gonna see if I can get TSP to get me a new set of bolts and gaskets for cheap since they are brand new

Certainly sounds like a lifter. Maybe you should see if all of the rockers are getting oil. If one isn't, that would be the bad lifter.

How would I know if it wasn't ?

Mock up the car so it can run without the valve covers ?

That I'm not sure :lol: but yeah, I would run it without the valve cover on. Otherwise, you are shotgunning lifters into there.

Yes

I cranked it with the valve covers off didn't run it though.
Didn't see anything and didn't hear anything at that time. almost has to be driving to get it to happen then it will stay till it cools though

I sent TSP the videos maybe they will chime in and hopefully send me 8 new ones, head gasket and head bolts since I just spent 3k on them and more in the past

Start the car covers off. Oil isn't going to hose you down.

I'll try it when I get home from work today.

Do you have an old set of crappy valve covers? If so you can drill out holes over the location of the rockers. I did that in my gen1 sbc to adjust the rockers. I'm not sure about the ls engines but figured ill throw it out there. Good luck solving the issue

That's a great idea ! I may do that and just keep with my "special tools"

Such a waste of valve covers..

at the risk of scratching a nice one when you take it off a half dozen times its worth it.

Even the coils hide em now, they won't be soon

Thanks!

It's worth it to save an oil mess and the headache of cleaning up the splattered oil and scratching up your nice set of covers

He's only saying that because he's in need of a set to weld fittings onto now :lol:

It does sound like a lifter. Does it always misfire when it's making that noise? I'm surprised it's not setting a code. If you were closer I'd monitor the misfire's with my Tech 2...

the one night it happened was really apparent it started missing but when I took it to work last week to pull the head it only felt like it was missing at idle.

But I pulled the driver side head and found 2 lifters o can compress the plunger by pushing on with my finger. 6 felt pretty solid.

Either way I have 8 on the way.

Lessons learned: When the time comes, I'm staying away from LS7 lifters… and getting ARP bolts :lol:

Got a suggestions on lifters? I was gonna get LS7's...

I think you just here of more issues with ls7 due to the popularity.

My last cam install and my buddies 6.0 both had no issues with the ls7s

Think a lot of people through around the name morel on tech

At least half of mine were bad out of the box from the dealer. I went with morel/lunati link bars and they have been great.

IDK bout half, but I would say a few of mine are bad as well.