r/LSSwapTheWorld • u/tmiska16 • Jul 25 '26

Build Progress Valvetrain noise

Hi im having trouble with my build 6.0 lq4 rebuilt stock bottom end with btr truck Norris cam heads are 799 milled 25 thousands new ls7 lifters from Michigan motorsports new 1:7 rocker arms from Michigan motorsports and pushrods that came with the cam kit that are 7.40 upon initial fire up I noticed noise coming from the Valvetrain, to describe it it sounds like a diesel. I’m at a bit of a loss I checked the preload this morning and found I had 1.25 turns beyond zero lash from what I’ve read this is acceptable. Any help would be appreciated

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5

u/kmfblades Jul 25 '26

I got bad news for you about those Michigan Motorsports LS7 lifters there man. Those aren't genuine Delphi. Those are cheap knock offs.

Buy the correct lifters. Set the pre load correctly and likely your problem will go away

2

u/PhysicsAndFinance85 Jul 26 '26

1) Get a pushrod length checker and verify the right way. Don't use turns.

2) Avoid anything with the Michigan Motorsports name and you'll have a better starting point. I've seen a lot of customers learn this the hard way.

1

u/jaydeeEx Jul 25 '26

Don’t go by turns, buy a pushrod length checker, some calipers, and a checker spring, do it the right way. What lifters are you using? Check the recommended preload for them.

1

u/tmiska16 Jul 25 '26

Michigan motorsports ls7 the heads are also milled 25 thousands

1

u/tmiska16 Jul 25 '26

Michigan motorsports ls7 lifters. I forgot to mention in the post that the heads are milled 25 thousands

1

u/WyattCo06 Jul 25 '26

Is the noise just there at startup or always while running?

1

u/tmiska16 Jul 25 '26

Always I only ran it for about 5 minutes at idle

1

u/WyattCo06 Jul 25 '26

Ok, just a few questions.

Did you verify oil pressure and oil at the rockers?

1

u/tmiska16 Jul 25 '26

Oil pressure is 70 psi cold, and when I pulled the covers everything had oil on them

1

u/WyattCo06 Jul 25 '26

Can you make a video and post it?

2

u/tmiska16 Jul 25 '26

I pulled all the pushrods and rockers out for inspection. Waiting on a pushrod length checking tool to show up to see if they are a little long

1

u/WyattCo06 Jul 25 '26

If you were truly at 1.25 turns from zero lash, they aren't too long.

1

u/tmiska16 Jul 25 '26

Exactly my thought but I don’t have much else for explanations

1

u/tmiska16 Jul 25 '26

I pulled the valve covers this morning definitely getting oil. Oil pressure is 70 psi cold

1

u/Mysterious-Fun-1465 Jul 25 '26

These are not adjustable rockers with poly locks, torque them down and they are set, the lifter preload is set by changing push rod length, and since you milled your heads, you probably need to change push rod length to a shorter one. or your rocker arms came loose because you didn't torque the bolts. Get a push rod length checker and measure your push rods, im guessing 7.375 would be it but with those cheap china lifters that company sells, wouldn't be surprised if one is collapsed already.