bdeming

okay so, my ls1 makes this terrible ticking sound once its warmed up, sounds just like a cracked primary on the header. I removed the heat wrap and inspected the header for cracks, no cracks found, no leaks found at the gasket either. i thought it might be the lifters, so i replaced my lifters with the oem ls7 lifters, made no difference. when it starts ticking you can hear the difference in the exhaust tone.

the motor has a 228r cam, TSP pushrods, and pac springs. i used 7.400 pushrods i did not check the pushrod length. could the wrong length pushrods cause this? anymore ideas? thank you!

Darkman

iTrader: (2)

Yes, incorrect preload can cause ticking, but it should be "clatter" since all of the cylinders would be making noise. It could also be a noisy fuel injector.

BKsNHRA

iTrader: (4)

This is what mine was doing. I Chased this problem for about 10 months. COuldent find it. CHange lifters a few different sets of pushrods. rebuilt the heads. You name it I did it. I was at the point of pulling the motor because I couldent find it and the engine just wouldent die either. I pulled the oil pump as a last resort. I had no signs of a oil pressure problem but their it was. A split oil pump oring. I replaced the pump and oring and haven't had a problem since.

BKsNHRA

iTrader: (4)

Here is was. This was the oring that came with the car. Not one I put in. Dryed up shrunk up and broke. Seems they do this with age and my car has low miles so it sat a lot.

bdeming

its deffinatly not "clatter", it sounds just like the video posted, the ticking speeds up with the rpm. I replaced my o-ring and got the "newer" ls6 oil pump that also made no difference. ive got the oil pump off now so i could degree my cam, the o-ring looks fine. what i dont understand is why i can hear the difference in the exhuast when it starts ticking, while at idle and while driving.

Darkman

iTrader: (2)

I would at least check the preload. It could be that the preload is borderline such that all but one lifter is happy.

bdeming

okay i don't have a pushrod length checker so I broke the torque on the rocker and then snugged the bolt up by hand, the rocker seated in the pedestal. the cylinder at TDC both valves closed. I can spin the pushrods with my fingers. and I can the rocker a little bit, but it does not loose contact with the pushrod (the lifter keeps some pressure on the pushrod), it does loose contact with the valve. does this sound okay?

also with the rockers torqued at 22ft-lbs I can move the rockers side to side and up and down a little. the trunions seem to have a little play, is that normal?

Darkman

iTrader: (2)

The side to side play is normal. If you do not have pushrod checker you can use the method described in this post.

https://ls1tech.com/forums/16774455-post2.html

bdeming

thanks for that link! I just went and tried it, I came up with ~1.5 turns, and he says he shoots for 1.25-1.75 turns. im right in the middle. so the push rods should be all set!

Darkman

iTrader: (2)

Sounds good on the preload. Is the sound high enough in the engine compartment to be a noisy fuel injector?

bdeming

I don't think it would be a loud injector, it only makes the noise when it warms up, and the ticking increases when the rpm increases. I can tell its coming from the drivers side, but I cant tell where exactly

poltergeist 02

iTrader: (65)

That method is wrong. It doesn't take the 1.7 rocker ratio in to consideration. When I measured for pushrods (using LS7 lifters) a 7.375 pushrod was around .083" preload with stock unmilled heads. The lifter cup of the LS7 lifters sits .050" higher than the stock LS1 lifter, so using a 7.425 pushrod is going to put you well over .100" preload.

Darkman

iTrader: (2)

The OP is using a 7.40 pushrod and the 1.5 turns puts the preload at 0.0914 inch as corrected for both rocker ratio and bolt stretch.

poltergeist 02

iTrader: (65)

I don't know why I thought he was using 7.425" pushrods. With 7.40" I was just over .100" preload, I don't remember the exact number though.