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Old 03-18-2007, 02:36 PM
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Ok... I am having a tapping issues and I think the rockers need to be adjusted but I just want to get some feedback before I jump in there.

The motor had 1k miles on it when I bought it with 0 issues. It was not running 6-7 months before I got it (stored correct). I was told when a motor is down for that long the rockers and stuff need to be adjusted.

There is no drive loss and it only happens when the car warms up. I have changed the oil and there is nothing in it.

Is there a how-to on adjusting rockers?
Old 03-18-2007, 08:14 PM
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If they are stock rockers, they are non-adjustable.

What rockers are you running?
Old 03-19-2007, 06:21 AM
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Im having that same issue kind of. I bought my car and they previuos owner had just replaced all the bearings in the motor. Mine has no problems like yours except when its being started when its cold. When its warm no tapping. I had a respectable mechanic look at. He checked my compression, oil, pressure, and some other things. They all were to spec. He told me that sound i was hearing was a rod bearing. And that i would be replaceing the motor soon. So im curious as to what answer you come up with.
Old 03-19-2007, 07:21 AM
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I have heard rod knock and this is not a rod knock for sure. I can 100% hear it in the heads. They are aftermarket rockers, I forgot what brand but I think crane.
Old 03-19-2007, 07:23 AM
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They are adjustable, I would get in there and make sure they are adjusted right.
Old 03-19-2007, 07:52 AM
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There is no drive loss and it only happens when the car warms up. I have changed the oil and there is nothing in it.
If you only hear the noise during engine warm up then it's more than likely piston slap. This is very common on aluminum block engines and nothing to be worried about.
Old 03-19-2007, 08:04 AM
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Originally Posted by jub jub
If you only hear the noise during engine warm up then it's more than likely piston slap. This is very common on aluminum block engines and nothing to be worried about.
very well could be slap, but with adjustables i would double check them to be sure.
Old 03-19-2007, 08:55 AM
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Originally Posted by brad8266
very well could be slap, but with adjustables i would double check them to be sure.
Ditto...check them just to be safe...

Anything else you're hearing is probably slap...
Old 03-19-2007, 10:47 PM
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Originally Posted by xTraViSx
Im having that same issue kind of. I bought my car and they previuos owner had just replaced all the bearings in the motor. Mine has no problems like yours except when its being started when its cold. When its warm no tapping. I had a respectable mechanic look at. He checked my compression, oil, pressure, and some other things. They all were to spec. He told me that sound i was hearing was a rod bearing. And that i would be replaceing the motor soon. So im curious as to what answer you come up with.


i can tell u right now u dont have a spun bearing. if u did it would be a loud tapping and it would increase with rpms and it would not go away period. and you would have alot less power than normal.

now im still curious as to why everyone says its ok to have piston slap? its ok for my pistons to hit my valves? cuz last time i check that will bend the **** out of them lol. and also how are these rockers adjustable? they sit on the pushrod and valve stem and u bolt them to the head....soooo what am i missing here?
Old 03-20-2007, 08:07 AM
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Originally Posted by 96TransAmM6
i can tell u right now u dont have a spun bearing. if u did it would be a loud tapping and it would increase with rpms and it would not go away period. and you would have alot less power than normal.

now im still curious as to why everyone says its ok to have piston slap? its ok for my pistons to hit my valves? cuz last time i check that will bend the **** out of them lol. and also how are these rockers adjustable? they sit on the pushrod and valve stem and u bolt them to the head....soooo what am i missing here?
Piston slap has nothing at all to do with the piston hitting the valves...

Piston slap is to due the piston and sleeve being made of two different materials...hence two different rates of expansion when heated. It's typically more prevalent when the engine is cold and is less audible when the engine warms up.

Last edited by marv; 03-20-2007 at 10:54 AM.
Old 03-20-2007, 10:31 AM
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If your car sounds like a diesel on a cold start then it's probably piston slap.

But if you have adjustable rockers I would start with them.

Also, just curious but what weight oil are you running and what's the outside temp when your having these issues?
Old 03-20-2007, 10:58 AM
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I'm noticing a noise after warmup as well, but only over 3,000RPMS. I'm running Amsoil Full Synthetic 5w30. Motor has approx. 1200 miles on it... Could the weight be the reason?
Old 03-20-2007, 09:52 PM
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Originally Posted by JLSain
I'm noticing a noise after warmup as well, but only over 3,000RPMS. I'm running Amsoil Full Synthetic 5w30. Motor has approx. 1200 miles on it... Could the weight be the reason?

oh hell yeah change your oil to 30 weight. or atleast like some 10w30.....5w30 is ok if it never gets hotter than 70 degrees outside lol but here where im at it gets up to 100 on average in the summer

10w30 is reccommended for our cars but thats reccommended all over the us so they cant take in to account weather conditions. thats why all the foreign cars suggest 5w30 cuz it never gets hot in germany haha. anyways ditch the synthetic that stuff sucks *** you need something thicker
Old 03-21-2007, 06:43 AM
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10W30. Put oil is thin when I checked it. Its running really rich now so I think there might be some fuel in there also.

Were going to adjust the rockers and change the oil and see what I come back with,
Old 03-21-2007, 07:15 AM
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it could be the common valve train tap that you hear in most ls1's, or piston slap
Old 03-21-2007, 07:29 AM
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Originally Posted by 96TransAmM6
oh hell yeah change your oil to 30 weight. or atleast like some 10w30.....5w30 is ok if it never gets hotter than 70 degrees outside lol but here where im at it gets up to 100 on average in the summer

10w30 is reccommended for our cars but thats reccommended all over the us so they cant take in to account weather conditions. thats why all the foreign cars suggest 5w30 cuz it never gets hot in germany haha. anyways ditch the synthetic that stuff sucks *** you need something thicker
Not that I don't believe you, but how many other guys are doing this? My engine only has 1200 miles on it! OEM calls for 5w30. The weather here in Charlotte, NC goes from 20 degrees at night in the winter, upwards of 100 degrees in the summer.

I find it hard to believe that 10w30 will make that noise go away.

By the way, maybe I jinxed myself by talking about how good my oil pressure was yesterday. I was driving around town yesterday and noticed my oil pressure gauge drop down to about 23PSI at idle and the needle was a little jerky. When I cut the car off, the needle would "stick" at wherever it was before I shut the car off. If I turn the key on and back off without cranking the engine, the needle would reset itself and go to zero.




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