Knocking or pinging?
Thread Starter
Drifting
Joined: Aug 2004
Posts: 1,677
Likes: 1
From: Potomac Falls VA
Knocking or pinging?
This morning I drove my car to work since i is supposed to be 75 and sunny in NoVA. Car sounded a little different so when I got to work I opened the hood and took a listen. Heard a (best I can describe as) a tapping noise from the drivers side of the engine.
The engine is a almost brand new Jasper 383 (less than 500 miles) and I just recently put 93 octane in it instead of the 91 I have been going with and I am wondering if that could have something to do with it?
Thanks
Shane
The engine is a almost brand new Jasper 383 (less than 500 miles) and I just recently put 93 octane in it instead of the 91 I have been going with and I am wondering if that could have something to do with it?
Thanks
Shane
Thread Starter
Drifting
Joined: Aug 2004
Posts: 1,677
Likes: 1
From: Potomac Falls VA
A little bit more information....
Here is the link to the spec sheet for the engine. I had them also include intake and car as listed ont he bottom right.
Compression is approx 9.4:1
Here is the link to the spec sheet for the engine. I had them also include intake and car as listed ont he bottom right.
Compression is approx 9.4:1
Le Mans Master
Joined: Oct 2004
Posts: 5,269
Likes: 54
From: Orlando Florida
St. Jude Donor '05
93 octane should not have any negative effect (other than on your wallet). If it runs fine on 91 that's what I'd buy.
The noise:
Hopefully it's only a loose rocker arm. What type of lifters do you have ? hydr./solid flat tappet or roller ??
Rocker arm nuts can come loose, did you use 'stock' or 'locking' nuts ?
I'd take the valve cover off and have a look ...
G/L
The noise:
Hopefully it's only a loose rocker arm. What type of lifters do you have ? hydr./solid flat tappet or roller ??
Rocker arm nuts can come loose, did you use 'stock' or 'locking' nuts ?
I'd take the valve cover off and have a look ...
G/L
Thread Starter
Drifting
Joined: Aug 2004
Posts: 1,677
Likes: 1
From: Potomac Falls VA
Originally Posted by RedBad1979
93 octane should not have any negative effect (other than on your wallet). If it runs fine on 91 that's what I'd buy.
The noise:
Hopefully it's only a loose rocker arm. What type of lifters do you have ? hydr./solid flat tappet or roller ??
Rocker arm nuts can come loose, did you use 'stock' or 'locking' nuts ?
I'd take the valve cover off and have a look ...
G/L
The noise:
Hopefully it's only a loose rocker arm. What type of lifters do you have ? hydr./solid flat tappet or roller ??
Rocker arm nuts can come loose, did you use 'stock' or 'locking' nuts ?
I'd take the valve cover off and have a look ...
G/L
Will a loose rocker arm be pretty obvious by manually handling each one in succession? Do you know the torque settings by chance if that were to come loose?
Le Mans Master
Joined: Oct 2004
Posts: 5,269
Likes: 54
From: Orlando Florida
St. Jude Donor '05
Originally Posted by ShaneLU97
Not sure on the lifters or nuts. I will check the detailed build sheet when I get home. As for the nuts, not sure on that either.
Will a loose rocker arm be pretty obvious by manually handling each one in succession? Do you know the torque settings by chance if that were to come loose?
Will a loose rocker arm be pretty obvious by manually handling each one in succession? Do you know the torque settings by chance if that were to come loose?
If you have hydraulic lifters it's possible that a lifter collapsed or simply failed.
These are the inexpensive options... I hope it's not a wiped camshaft lope
Thread Starter
Drifting
Joined: Aug 2004
Posts: 1,677
Likes: 1
From: Potomac Falls VA
Would there be other symptoms for a wiped lobe? What would cause this? The engine was properly broken before they shipped it (part of their turn-key package) and they said theonly thing I should do is an oil change after the first 500 miles and then on a regular schedule after that.
Thanks
Shane
Thanks
Shane
Le Mans Master
Joined: Oct 2004
Posts: 5,269
Likes: 54
From: Orlando Florida
St. Jude Donor '05
To see a wiped lope you have to pull the lifters, this is possible without taking the intake off. You have to use a lifter puller (or a "magnet on a stick") thru the pushrod opening in the heads. Pull one lifter, look at the cam lobe and the bottom of the lifter, re-install or tear down the engine depending on findings....
What causes it ? There are many discussions going on on this forum, many members reported wiped lobes. Some say it's the low zinc content in modern oils, some say it's the agressive cam profile on modern cams... the manufacturers (of course) mostly say it's "improper break in procedure'...
Take the valve covers off, inspect and see what you find... it's hopefully only a loose rocker nut.
BTW, a header leak can sound like a ticking noise. Make sure you don't have a leaking header gasket.
What causes it ? There are many discussions going on on this forum, many members reported wiped lobes. Some say it's the low zinc content in modern oils, some say it's the agressive cam profile on modern cams... the manufacturers (of course) mostly say it's "improper break in procedure'...
Take the valve covers off, inspect and see what you find... it's hopefully only a loose rocker nut.
BTW, a header leak can sound like a ticking noise. Make sure you don't have a leaking header gasket.
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Thread Starter
Drifting
Joined: Aug 2004
Posts: 1,677
Likes: 1
From: Potomac Falls VA
Originally Posted by RedBad1979
Any news ?? What did you find ??
Thanks again for the input and reminder!!
Le Mans Master
Joined: Oct 2004
Posts: 5,269
Likes: 54
From: Orlando Florida
St. Jude Donor '05
Originally Posted by ShaneLU97
Actually, yes. Your comment about the potential header gasket leak led me to a slap to my own forehead for forgetting an obvious one. On the way home I picked up a mechanics stethoscope (during which time I joked with the guy at the parts store that my wife is truly going to think this is by far the WEIRDEST car tool I have ever bought) and went around the header gasket area of the passenger side (side with no noise...consistent sounds all around) and then around the drivers side where the noise is and when I got to the top/center of the header gasket it got really loud all of a sudden so it looks like there is where my leak is.
Thanks again for the input and reminder!!
Thanks again for the input and reminder!!
Isn't it great when it's something simple ??
When the engine/header is cold spray some foam (shaving foam works great) in that area, then start the engine and turn it off again... you'll see where the leak is
I had header leaks before and got Breslin locking bolts (Summit or Jegs). these are expensive but worth the money