Noisy Lifters????

[tblake]

Hey everyone!!! I have a question about my girlfriends 2002 grand prix se 3100sfi, 75,000 miles. Last winter we put a lower intake gasket in it if you remember... http://www.automotiveforums.com/vbul...d.php?t=656443 Its still running great, but to me it seems the lifters have gotten noisy, or maybe they were even noisy before we did the LIM gasket job and I didnt notice. I am 100% sure that the slight ticking is because of the lifters. It seems worse at cold startup, but when its up to temperature they get a lot quieter. As you probably know, I used to drive a lumina with the same motor in it so im used to the 3.1 tick, but my lifters were no where near as noisy. We have kept up on oil changes every 3,000 miles and only use a Wix or AC delco filter and valvoline 5w30. My best guess would be maybe that the previous owner drove it too long with a leaking LIM and damaged the lifters. When she got it, the gasket was leaking bad. No longer is it leaking, coolant is always full, with no evidence of water in the oil. What would you guys recommend? The car starts and runs fine, it just seems a little too noisy to me. I hear all these even older 60 degree GM V6 motors start with no tick tick at all. Maybe the lifters need replacing? I am 100% sure that when we did the LIM, that all the pushrods all went back in in the same place. If it gets too bad, where would you recommend we buy a set of lifters, maybe not very expensive? Thanks everyone!!!!!!!!!!

[BNaylor]

Is the ticking sound persistent even after sufficient engine warmup? Does it disappear at all? Hard to say but the Vin "J" 3100 engines have been known to suffer from piston slap which may sound similar. Big difference compared to the Vin "M" 3100. I had a '96 Lumina Sedan with the 3100 Vin "M" and I recall the engine was quiet even with over 80K miles.

What rocker arm torquing procedure did you use after doing the LIM job?

[tblake]

Thanks for the response bnaylor! The noise gets a lot quiter when the engine warms up, but i dont think it ever completly goes away. Whats the difference between the vin "M" and "J" 3100's? I dont remember the exact torque on the rockers. Maybe like 16ftlbs and an aditional 30 degrees or something along that line if i remember correctly. I was thinking about removing the valve covers on a cold engine, removing the fuel pump relay, and then have someone crank it over while I feel for play as the rockers move. It totally sounds like a lifter problem to me, but i suppose it could be piston slap. I've never heard piston slap, or if I have, No one has ever pointed it out, so I dont know what to listen for (if that makes sense). I do know that this tick is very fast so thats why I assume that its coming from the top end and not the bottem end.

[BNaylor]

Alot of current GM engine suffer from piston slap. See www.pistonslap.com for some insight. We get the sound which does sound like a lifter in my son's '02 Olds Alero GL2 with the Vin "E" 60 degree 3400 engine but it disappears after approximately 60 seconds. Not much you can do about it if it is piston slap. GM changed the composition of pistons and engine build technique. My experiences with bad lifters is they stay noisy and get worse when the engine fully warms up.

But to be sure I'd double check the rocker arms and re-torque.

[tblake]

thank you for the insight. This sould lasts a lot longer than 60 seconds. It will stay untill the temp guage hits the first notch. I think i will do like you say and retorque the rockers, but i dont see how mis torqued rockers will make noise and when the engine warms make a lot less noise. Wouldnt they just keep making noise?

[BNaylor]

Just a suggestion since you didn't know if the noise was there before doing the LIM job. Doesn't hurt to double check the work before shelling out money on parts that may not resolve the issue. It does matter and every part in the valvetrain overlaps or interreacts. Even though it is a hydraulic lifter the torquing procedure preloads the lifter(s).

As I mentioned earlier a sticky lifter remains noisy and gets worse when you rev up the engine. A collapsed lifter is even worse. Piston slap normally disappears once the engine warms up.

FAQS:

What is Hydraulic Lifter Preload?
Mechanical cam designs require a running clearance or valve lash; hydraulic lifters are just the opposite. When the rocker arm assembly is properly torqued down into position, the pushrod must take up all the clearance and descend into the hydraulic lifter, causing the pushrod seat to move down by .020 to .060. The distance that the pushrod seat moves down away from the retaining lock is the Lifter Preload. The hydraulic mechanism requires this precise amount of preload for it to do its job properly.

What happens if the amount of Hydraulic Lifter Preload is wrong?
If clearance exists between the pushrod and the seat in the hydraulic lifter, after the rocker arm assembly has been torqued down, you will have no lifter preload. In this case the valve train will be noisy when the engine is running. All of the hydraulic force produced by the lifter will be exerted against the lifters retaining lock, and this could cause the lock to fail.

[tblake]

Ok thankyou. I will defenatly check out the rocker arm torque.

[troy1]

My 3800 rattles a tiny bit to after start up. She's gonna blow captin LOL