Another tapping LS1 (did search)
Thread Starter
TECH Enthusiast
Joined: Jul 2002
Posts: 653
Likes: 0
From: Mannheim, Germany
Bad lifter ?? (did search) I did a couple searches and I haven't come with anything yet. Here are my symptoms:
The tapping first occured about 5 minutes after I installed the hotcam.
Loud tapping coming from driver side of engine.
The sound isn't there all of the time. I drove for about 20 minutes today before it showed up.
It seems like if I give some WOT treatments, it goes away but eventually comes back.
I think it's more prone to tap after the engine is fully warmed up.
All plug wires are firmly seated.
All of my rockers looked good during the install.
The car idles/runs fine and has good power. (I broke my torque arm the other day so I think I'm making decent power
)
Frequency is one tap/rpm.
It's quite loud. I can easily hear it over my exhaust while cruising.
I shut off the ignition while cruising @ 40 mph and the tap did not go away or change. (I think that eliminates ignition and fuel injectors right?)
The strange thing is that it's intermittant.
Any help/suggestions would be great. I'm stumped.
I'm gonna go swap all of the plug wires from each side of the engine to see if the tapping goes to the passenger side once it cools down. I don't think that's gonna do anything though since the tapping didn't go away even with the ignition off.
The tapping first occured about 5 minutes after I installed the hotcam.
Loud tapping coming from driver side of engine.
The sound isn't there all of the time. I drove for about 20 minutes today before it showed up.
It seems like if I give some WOT treatments, it goes away but eventually comes back.
I think it's more prone to tap after the engine is fully warmed up.
All plug wires are firmly seated.
All of my rockers looked good during the install.
The car idles/runs fine and has good power. (I broke my torque arm the other day so I think I'm making decent power
)Frequency is one tap/rpm.
It's quite loud. I can easily hear it over my exhaust while cruising.
I shut off the ignition while cruising @ 40 mph and the tap did not go away or change. (I think that eliminates ignition and fuel injectors right?)
The strange thing is that it's intermittant.
Any help/suggestions would be great. I'm stumped.
I'm gonna go swap all of the plug wires from each side of the engine to see if the tapping goes to the passenger side once it cools down. I don't think that's gonna do anything though since the tapping didn't go away even with the ignition off.
Last edited by kenkaru; Jul 25, 2004 at 03:46 PM.
Thread Starter
TECH Enthusiast
Joined: Jul 2002
Posts: 653
Likes: 0
From: Mannheim, Germany
I drove it a little more. It doesn't tap on a cold start if the cars been sittine 30 min or more. After about 5 minutes of driving, the tapping begins. I'm thinking I really need to get this figured out before it gets worse.
Thread Starter
TECH Enthusiast
Joined: Jul 2002
Posts: 653
Likes: 0
From: Mannheim, Germany
ha I feel like I'm talking to myself here... just in case anyone else has this problem, there is a GM TSB on this that says it's the oil pump O ring. I found that info on the "other" message board. I order a couple so I'm gonna try that out. I'll post an update
Trending Topics
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
Five Reasons the Camaro Was the Most Pivotal Player in the Pony Car Wars 2.0
Brett Foote
10 Reasons the LS7 Is GM's Most Extreme Naturally Aspirated V8 Engine Ever
Verdad Gallardo
TECH Enthusiast
Joined: May 2004
Posts: 622
Likes: 0
From: Northern Illinios
check the pushrods and rocker arms again.... they might have bent if they were torque'd wrong. make sure your rockers are good. If neither, maybe a valve or lifter.
How is the compression?
How is the compression?
my rockers are stock. I had to sell my yella terras because they didn't fit under my '98 valve covers. I'm gonna go pull my valve cover right now to check it out.
and I'm still waiting for that "verification number" for Paypal... give me a couple days...
Back to your problem.....seems like it gets worse once your engine warms up....(metals expand when Temp. increases) I would check the cleareance again... makes sure it's all torqued to specification....
Thread Starter
TECH Enthusiast
Joined: Jul 2002
Posts: 653
Likes: 0
From: Mannheim, Germany
well, during lunch, I pulled the valve cover and tried to jiggle everything by hand and visually checked everything but didn't notice anything wrong. I didn't have a torque wrench.
Can someone please explain how our hydraulic lifters work? I'm thinking it's either a lifter or the o ring because the sound definitely only occurs after the oil is warmed up and my oil pressure starts lowering because of the oil thinning. I get about 42 PSI idle at startup but once the oil thins, it will sometimes go down as low as 20 PSI at idle. I can watch the oil gauge and once it starts going down, the tapping begins shortly after.
I'll double check my torque on wed when the auto center on base opens.
Can someone please explain how our hydraulic lifters work? I'm thinking it's either a lifter or the o ring because the sound definitely only occurs after the oil is warmed up and my oil pressure starts lowering because of the oil thinning. I get about 42 PSI idle at startup but once the oil thins, it will sometimes go down as low as 20 PSI at idle. I can watch the oil gauge and once it starts going down, the tapping begins shortly after.
I'll double check my torque on wed when the auto center on base opens.
Sure does sound like a lifter to me, buy a bottle of lifter treatment. The stuff for stuck lifters, add it to your oil and see if the noise goes away and stays away. If it goes away and doesn't come back then it was just a bit of gunk in lifter, if it goes away and comes back then lifter has something wrong with its plunger. Get new lifters then if you can't stand the tapping noise.
Mine made the same noise as yours ended up being a spun bearing. I was shure it was a lifter until I pulled the motor apart. My car also ran 20psi when sitting and 40psi when driving.
TECH Enthusiast
Joined: Jun 2002
Posts: 634
Likes: 0
From: In the garage fixing LT1
Checking lash: Get your spark plug gapper. Measure space between valve and rocker on problem cylinder with the pushrod in it's retracted position for each valve to be measured. Do both the intake and the exhaust. Come back here and tell us what it is. But bad lash or pushrod will get better as the engine heats up. Bad lifter will get worse as the engine heats up and the oil gets thinner. Still, it could be any three.
Can't remember what the lash should be offhand. I *think* it's .024 intake and .026 exhaust but I can't remember. Someone here must know.
Can't remember what the lash should be offhand. I *think* it's .024 intake and .026 exhaust but I can't remember. Someone here must know.
Thread Starter
TECH Enthusiast
Joined: Jul 2002
Posts: 653
Likes: 0
From: Mannheim, Germany
OK I'm a moron... I think I might know what the problem is. When I installed my oil pump, I over-torqued one of the bolts that hold the body halves together so it stripped a little. It still had about 6-7 ft/lbs of hold in it so I just left it. Maybe the oil is leaking out of the pump body when it gets thinner?
You probably just have a lifter that is going bad because the plunger has too much clearance and when the oil gets thinner as it gets warmer, the lifter can't stay completely pumped up. There is no lash adjustment on our cars unless you have aftermarket rocker arms. It is a non-adjustable setup. Hope this helps.
Thread Starter
TECH Enthusiast
Joined: Jul 2002
Posts: 653
Likes: 0
From: Mannheim, Germany
ok so here's my plan of action:
1) I try some CD2 engine treatment stuff.
if that doesn't work,
2) I was thinking about 15w40. would that help/be ok?
3)I go back into the engine and slap a helicoil into my oil pump
if that still doesn't fix it
4) do I NEED to replace the lifter? where can I get a good deal on lifters?
I'm getting married on oct 1st and this cam swap was supposed to be the last of mods for my car for a looong time. The day I finished the install, I broke my torque arm and damaged my driveshaft in the process. I'm way over my car budget already so I need to know if I can just turn up my radio and call it FIXED.
1) I try some CD2 engine treatment stuff.
if that doesn't work,
2) I was thinking about 15w40. would that help/be ok?
3)I go back into the engine and slap a helicoil into my oil pump
if that still doesn't fix it
4) do I NEED to replace the lifter? where can I get a good deal on lifters?
I'm getting married on oct 1st and this cam swap was supposed to be the last of mods for my car for a looong time. The day I finished the install, I broke my torque arm and damaged my driveshaft in the process. I'm way over my car budget already so I need to know if I can just turn up my radio and call it FIXED.