patrick983

Ok Im pretty new here... and pretty new to these LS engines. I promise this isnt a redundant thread...i know how to search.

I purchased my dream car off a fellow forum member recently and received it...everythings good except the motor...making an incredibly loud tick. Not the "normal" LS7 tick (not my first z06). I can tell by the frequency that its 1 driver side cyl creating the loud tapping noise. This car has heads by AI, a larger cam, 1.8 rockers, an expensive set of Lunati link bar lifters so i was feeling confident the build was right...and i think it is, after this one issue is resolved. The car exhibits no loss in power.

Today i pulled the valve cover and noticed one rocker arm is unusually loose. Im looking for some feedback from guys with more hands-on time with these engines/rockers. ive attached a video and any feedback is greatly appreciated!!

djbrun

with another cylinder on top dead center, what is the lash clearance?

What is that cylinder compared to the one in question?

You could a dial indicator at the end of the rocker to compare lifts? Intake to intake valve. This would tell you if your lifter and cam lobe are ok.

Have you removed the rocker and checked the stud?


DJ

patrick983

cylinder in question is on exhaust stroke, exhaust valve is open. so i assumed this valve should be fully closed and should not be moving as such. i will pull plugs and locate the pistons after work and report back. ill also go ahead and pull that rocker off and inspect it. thank you for your help so far!

ttx350z

Has it made that noise since day 1? Since that's an intake valve. It looks like there's no lash cap on it.

Or if it's an aftermarket valve, the hardened tip could've broken off. Trick had intake valves with that issue.

Remove the rocker to find out for sure. What year is your car? 2007? It could be the bad needle bearings in the rocker as well.

erick_e

I'm watching on my phone so it's hard to see, but it looks like the rocker arm bearings fell out and that's causing that play.

patrick983

a little more research and im hoping its just bad needle bearings. Im at work but the car is new to me so not sure how long its been making the noise, but its an 08 with only 9k miles. I know it was put together by Complete Street Performance in PA. i would hope they would of covered all the bases with a build like this. Looks to be stock 1.8 rockers. It has AI 280cc heads and one of thei cam grinds installed. Im working all night but in the morning ill remove the rocker arm and take a closer look then rotate the engine and check a few more.

subfloor@centurytrans

Pull out that one pushrod and roll it over a smooth, flat surface - I'm betting you'll find that it's bent.

Complete Street

If it is the car I am thinking of, it was not assembled by us. We did provide parts, but the install was performed by the owner at his house. We also tuned it.

Let us know what you find!

Andrew

patrick983

Andrew, thanks for your reply. Im learning each day it seems this car was not properly represented at all.
I will PM you but hoping to maybe pick your brain at some point and maybe order some parts to make this a little more reliable build.

Pushrod is straight, no other rockers have as much play as that one as i rotate the engine. Have not checked actual lift height so im not 100% sure theres not a problem there as well but i removed that rocked and can wiggle the trunion within the rocker all directions. weird thing i cant see any needle bearings missing and the cages are still intact...? ive got a new oem rocker to pick up in the morning so for $16 ill throw that on and see what it does. Definitely need to upgrade these rockers asap if that ends up being the cause.

Thanks for all the feedback so far guys.

ttx350z

Was there a lash cap on it?

Why not swap another intake rocker on it to see if the problem is still there?

If it still has the play, the rocker is not the issue.

ttx350z

Another thing to check is the valve spring. It could be broken, damaged, collapsed spring so there's is not sufficient pressure to seat the valve.

patrick983

was just thinking that... Don't know why I didn't think to ask earlier Thanks

erick_e

If the valve cover is still off, a higher quality video might help.

ttx350z

I know that you bought the car used already modded. But has it made that sound since day one of you owning it? Or did it sound fine and then the noise appeared. More info would help.

patrick983

You sir...are correct. After swapping rockers and no improvement, and double checking pushrod, i had a panic attack. and then realized the freaking cap was missing. Any body help me out with a part #?
ls7 intake valve cap or lash cap?

ttx350z

How'd the valve tip look? Any damage?

Lash cap part #12596509

patrick983

cant see any damage. going to replace the rocker anyway since i ordered one. upgrading these asap. theres noticeable play in all of these... i guess thats "normal"?

ttx350z

Some of mine have side to side. But i think that has more to do with whether or not the rocker has pressure on the valve or not. I don't the OEM rockers are a weak spot. It seems like I see more issues with after market ones then OEM (not including the bad batch of 2007).

It doesn't look damaged in the picture. Can you fit a lash cap from another intake valve on it with no problems?

Complete Street

Do the rest of the intake valves have the lash caps on them? I know he had them when he did the install.

patrick983

Yea only cyl 5 is missing the cap. If i could just get my hands on a cap hopefully ill be able to finally enjoy this beast. Ordered one tonight but hoping to find some local stock...

Ive read about the needle bearings in the stock rockers falling out, particularly with the added stresses of a cam, researched the comp cam trunion upgrade and think i will throw that ob there for piece of mind. Do you guys recommend this kit? looks like a pretty straight forward install and not alot of $$

lastly heres a pic of the rocker that was running without cap (forward) compared to rocker off another cyl (rearward). might be hard to see but theres a little more wear on the one without the cap. as well as some marking on the trunion. Replacing this snyway just for piece of mind.