Tapping sound in the engine. Time to upgrade valvetrain?

[Naaman]

I've got an annoying little tapping, kinda whispering sound when the engine is running. Friends and teacher (who've heard the noise) say a lifter is likely the cause.

I have read about upgrading the valve train (something about 1.7:1 ratios etc), and am wondering: If I upgrade the valve train, what else will I have to do to keep the car running normally? Can I get (for example) an LS6 valve train and just leave it at that?

I've got plans to port the heads and upgrade to a mild cam. Can I do this incrementally (valve train now, porting later, cam even later)?

I've tried to research all of this stuff, but I just don't understand camshafts enough to put it all together for myself yet.

Any recommendations on other valve train options?

[Hi-Po]

I've got an annoying little tapping, kinda whispering sound when the engine is running. Friends and teacher (who've heard the noise) say a lifter is likely the cause.

I have read about upgrading the valve train (something about 1.7:1 ratios etc), and am wondering: If I upgrade the valve train, what else will I have to do to keep the car running normally? Can I get (for example) an LS6 valve train and just leave it at that?

I've got plans to port the heads and upgrade to a mild cam. Can I do this incrementally (valve train now, porting later, cam even later)?

I've tried to research all of this stuff, but I just don't understand camshafts enough to put it all together for myself yet.

Any recommendations on other valve train options?

The 1.7 ratio you are referring to is the rocker arm ratio. Leave that stock, at 1.7.

These cars have a noisy valve train to begin with. If the sound isn't major and isn't down on power, I wouldn't go replacing things on a teachers ear. To get to the lifters the heads must be removed. If your removing the heads you might as well install the camshaft of your choice at that time as that's a fairly large job. No offense to you, but you don't sound like you've done this before.

If your set on replacing lifters and the noise is something serious I would go with LS7 lifters, a PAC or COMP single valve spring. If the noise isn't something serious I would save your pennies and install the camshaft, ported/aftermarket heads, lifters and springs all at once. Taking the heads on and off is a back ache if doing them while the engine is still in the car. But to answer your original question, of course you can do things in steps as the money flows in. It's just not the most economical way of doing things; for multiple reasons stated above.

Good luck.

[Naaman]

Awesome. Thanks for the reply.

Yeah, I have not done much with cars yet. In school right now, but have only been doing theory so far, no actual tear downs or assemblies yet. Fortunately, I have the option of working on my own car, if I want for any given lab, so some of the stuff I get, I will be able to do with guidance and full resources (tools, lifts etc)....

[Hi-Po]

Awesome. Thanks for the reply.

Yeah, I have not done much with cars yet. In school right now, but have only been doing theory so far, no actual tear downs or assemblies yet. Fortunately, I have the option of working on my own car, if I want for any given lab, so some of the stuff I get, I will be able to do with guidance and full resources (tools, lifts etc)....

Sounds fun.

If you want to learn and have some spare money, do your camshaft swap now. You can do heads later if you don't have the coin at the moment. I assume you have a lift at this school for you to use, that will make this job much easier. You will learn a ton from just swapping out the camshaft.

[Lunatikgixxer]

Is it noisy or are you getting a ticking noise?

[justinmc978]

if you arent doing so, run premium gas through it, many times this will stop lifter tap.

[redbird555]

if you arent doing so, run premium gas through it, many times this will stop lifter tap.

Premium fuel will do nothing for lifter tap maybe you're referring to pinging in engine caused by running lower grade fuel and getting pre-detonation? Noisy lifters are caused by either damaged lobes on the cam, lifter or a lifter not holding oil properly none of which have anything to do with fuel. Op maybe post a video up if you can, but it sounds like just a normal cause of ls valve chatter. These engines have a high cam ramp rate, coupled with an aluminum engine, and plastic intake tend to cause a loud valvetrain. So people used to older iron engines with metal intakkes are confused when they hear an ls1 that sounds like a sewing machine...

I think what you're hearing is piston slap which sometimes gets mistaken for a lifter because the two noises are similiar (dull in tone and come from the block) while valve chatter can be heard on the top of the head and is very light almost metallic in nature and tends to very with rpm almost perfectly. While piston slap with disappear above 2000 rpm.

One thing is for sure though, if you think its loud now wait till you get headers and a cam on there lol. It'll sound like a damn singer making clothes under the hood all the time lol.

[justinmc978]

Never had to do it on my car, but I have had a few friends through the years with LT1s and even a 5.9 durango that started to sound like a typewriter, told them all to run premium (per advice I heard as a child) and whatever it was, the noise stopped.

[redbird555]

Never had to do it on my car, but I have had a few friends through the years with LT1s and even a 5.9 durango that started to sound like a typewriter, told them all to run premium (per advice I heard as a child) and whatever it was, the noise stopped.

i suppose bad gas could cause excess carbon buildup on the valves making them noisy and the 93 with the additives in it from the station cleaned them off but that seems a little far fetched. i still say the op's issue is either not really an issue aka piston slap or he has valvetrain issues not likely though imo

[justinmc978]

i suppose bad gas could cause excess carbon buildup on the valves making them noisy and the 93 with the additives in it from the station cleaned them off but that seems a little far fetched. i still say the op's issue is either not really an issue aka piston slap or he has valvetrain issues not likely though imo

yeah, no idea.

to OP, kindof like Hi-po/redbird said, it's a noisy old chevy motor, a faint tapping isn't something I would be particularly worried about.

[Naaman]

UPDATE:

After a recent spark plug change, I noticed that the number 8 (and number 6, to a lesser extent) had some oil on the spark plug threads (no fouling, though). Teacher said it sounded like a leaking valve cover gasket. If redbird555 is correct, could it be that the leaking gasket is causing a lifter or two to be denied oil, thus causing the sound?

Here's a little more info: the tapping sound DOES accelerate proportionately with RPMs.

For what it's worth, I go out of my way to put premium Chevron into my car. If I must use other gas, I only pump in enough to get me to the next Chevron station (my car likes this gas best... I've tested).

[redbird555]

UPDATE:

After a recent spark plug change, I noticed that the number 8 (and number 6, to a lesser extent) had some oil on the spark plug threads (no fouling, though). Teacher said it sounded like a leaking valve cover gasket. If redbird555 is correct, could it be that the leaking gasket is causing a lifter or two to be denied oil, thus causing the sound?

Here's a little more info: the tapping sound DOES accelerate proportionately with RPMs.

For what it's worth, I go out of my way to put premium Chevron into my car. If I must use other gas, I only pump in enough to get me to the next Chevron station (my car likes this gas best... I've tested).

Its not all that uncommon to have a little bit of oil on the spark plug threads in these motors because oil does get into the cylinders at times from the less than stellar pcv system and generous piston tolerances. Also the tapping will move up and down with rpms even it is piston slap it will just go away after maybe 2000 rpms and even sometimes a lifter will too. If you really want a concrete diagnosis instead of what your teacher keeps throwing at you post up a short video and we'll see whats going on. But a bad valve cover gasket will not starve a lifter of oil because VERY little will escape the gasket...

No offense to your teacher but so far he's said everything from a leaking valve cover to a bad lifter after that I may start to call him into questioning lol

[prsz28]

Mine has just started something similar. When I first start the car there is a ticking noise, I suspect a lifter. It will go away in a couple of minutes of warm up and sounds fine after that. Other than that it still runs good at 73,000 miles. I love driving it. I ordered it new back in 99 and have been faithful at changing the oil every 3-4K miles. Started using Royal Purple right after break in. Any thoughts?
thanks,
max

[Hi-Po]

Mine has just started something similar. When I first start the car there is a ticking noise, I suspect a lifter. It will go away in a couple of minutes of warm up and sounds fine after that. Other than that it still runs good at 73,000 miles. I love driving it. I ordered it new back in 99 and have been faithful at changing the oil every 3-4K miles. Started using Royal Purple right after break in. Any thoughts?
thanks,
max

Normal. Drive the piss outta it, it's running fine.

[Jknerr]

Its not all that uncommon to have a little bit of oil on the spark plug threads in these motors because oil does get into the cylinders at times from the less than stellar pcv system and generous piston tolerances. Also the tapping will move up and down with rpms even it is piston slap it will just go away after maybe 2000 rpms and even sometimes a lifter will too. If you really want a concrete diagnosis instead of what your teacher keeps throwing at you post up a short video and we'll see whats going on. But a bad valve cover gasket will not starve a lifter of oil because VERY little will escape the gasket...

No offense to your teacher but so far he's said everything from a leaking valve cover to a bad lifter after that I may start to call him into questioning lol

OP redbird is right. a bad valve cover gasket would only allow a little oil to leak by, cause some oily steaks down the block, and account for some oil loss over time.

a mechanic at my work showed me a good method for identifing piston tap vs valve chatter. With the motor running, use a standard flat head screwdriver with a plastic handle. Place the metal end of the screw driver at different points on the engine, and hold the plastic end to your ear. it works allot like a stethoscope. just move from point to point on the engine and listen. There will be allot of weird and lound noises, but just listen for the same noise you are hearing outside the car. If it is piston slap it will ressonate and be the loudest on the block, and if its a valve problem you will hear it best on the heads.

Additionally if it is a lifter, this will help you trouble shoot which one has the problems. Also, the screwdrivers with the clear plastic seem to work better. I realize this is tacky ass hell but it really does work. Plus its free so why not give it a try.

[Jknerr]

Also, if it is a lifter issue, before replacing try running a different blend of oil. Allot of namebrand oils and expecially synteics use friction reducing compounds such as Molybdenum disulfide. While Moly and other compounds are fantastic high pressure limited wear lubricators, they can have a few unintional consequences. In hydraulic lifters, they occasionaly cause blockages that stop a lifter from functioning properly.

I would suggest using the same name brand (as mixing different blends commonly can cause the same problem) that you currently use, but check the back of the bottle for a circle that says "energy conserving". If your normal oil has this circle, have an oil change with a different blend that does not.

If your normal oil doesn't have that, you should consider making sure it does in the future for better wear characteristics. Instead of changing blends, run a cleaner through such as seafoam. Whoever's cleaner you use, check the manufactures website, becuase some of these like seafoam are expecially brutal if over used.

[Naaman]

OP redbird is right. a bad valve cover gasket would only allow a little oil to leak by, cause some oily steaks down the block, and account for some oil loss over time.

a mechanic at my work showed me a good method for identifing piston tap vs valve chatter. With the motor running, use a standard flat head screwdriver with a plastic handle. Place the metal end of the screw driver at different points on the engine, and hold the plastic end to your ear. it works allot like a stethoscope. just move from point to point on the engine and listen. There will be allot of weird and lound noises, but just listen for the same noise you are hearing outside the car. If it is piston slap it will ressonate and be the loudest on the block, and if its a valve problem you will hear it best on the heads.

Additionally if it is a lifter, this will help you trouble shoot which one has the problems. Also, the screwdrivers with the clear plastic seem to work better. I realize this is tacky ass hell but it really does work. Plus its free so why not give it a try.

I will have to try this. I've been using Mobil 1 for nearly two years (since I bough it). Not sure what was running in there prior.

[NaviDyn]

My Yukon has valvetrain noise when cold. I found a TSB online from GM. There isn't a fix unless you consider the part number they show from Comp Cams as a fix.

[Naaman]

Also, if it is a lifter issue, before replacing try running a different blend of oil. Allot of namebrand oils and expecially synteics use friction reducing compounds such as Molybdenum disulfide. While Moly and other compounds are fantastic high pressure limited wear lubricators, they can have a few unintional consequences. In hydraulic lifters, they occasionaly cause blockages that stop a lifter from functioning properly.

I would suggest using the same name brand (as mixing different blends commonly can cause the same problem) that you currently use, but check the back of the bottle for a circle that says "energy conserving". If your normal oil has this circle, have an oil change with a different blend that does not.

If your normal oil doesn't have that, you should consider making sure it does in the future for better wear characteristics. Instead of changing blends, run a cleaner through such as seafoam. Whoever's cleaner you use, check the manufactures website, becuase some of these like seafoam are expecially brutal if over used.

I am going to be changing the oil next week. I have heard that running a thicker oil through there (say, 40 weight) will increase oil pressure, and allow the lifter to retain proper lube/pressure (if that's the problem).

I'm tending to rule out piston slap, as the noise is constant: it does not go away as the car warms up, and it can be heard at any rpm that the engine/exhaust/road noise does not overwhelm it. Also, I did a smoke test on my car and there is no exhaust leak near the engine bay (there is a leak at the muffler, which is a stainless steel Magnaflow, mounted right under the bumper/trunk).

However, GM only recommends 30 weight, so I'm a little skeptical about putting 40 weight in there. I have also heard that Lucas makes an oil additive which, among other things, slightly increases viscosity, which could eliminate the sound (thus isolating the lifter, if it is the cause). Does anyone run oil stabilizers in their engine? What can I expect if I do?

[jiveass]

if you have been driving it for 6 months since this issue has been brought up and it is still running good, i dont think you have much to worry about. no spun bearings...no loss of power....just noisy valvetrain..