Cam walked backwards, how?
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Cam walked backwards, how?
I think we have solved my cam sensor problem. After pulling the plate that the knock sensors are in we were able to see that the cam had indeed walked, but not forward like everyone thought, it moved backward. Part of the roller lifters aren't ever touching the lobes! I know the cam plate keeps it from walking forward but what went wrong for it to slide back 1/4"? It wasn't making any noise from the front of the engine like I would imagine it doing if the timing gear were rubbing so what gives??
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Originally Posted by BLUEBALLS ZZ
dude. pull your front cover and check your timeing cam sproket! sound like your bolts on the sproket are backing out. thats what keeps the cam from going back
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Yep, my bolts didn't come completely out, but they had loosened up enough to allow the cam to walk backwards. There was enough play that the dowel pin (index pin) on the cam was knocked out and ended up as a chewed up chunk of metal in my oil pan. The cam walking was enough to get a lifter jammed in the lifter bore. Block was toast.
Not sure what might have caused yours, if this is indeed what happened. In my case, I used an online install guide that listed the torque spec for those bolts at 18 ft-lbs, instead of the correct 26 ft-lbs. That was 3 years ago and I'm not even sure that guide is still around.
Not sure what might have caused yours, if this is indeed what happened. In my case, I used an online install guide that listed the torque spec for those bolts at 18 ft-lbs, instead of the correct 26 ft-lbs. That was 3 years ago and I'm not even sure that guide is still around.
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Originally Posted by Go FasTA
Yep, my bolts didn't come completely out, but they had loosened up enough to allow the cam to walk backwards. There was enough play that the dowel pin (index pin) on the cam was knocked out and ended up as a chewed up chunk of metal in my oil pan. The cam walking was enough to get a lifter jammed in the lifter bore. Block was toast.
Not sure what might have caused yours, if this is indeed what happened. In my case, I used an online install guide that listed the torque spec for those bolts at 18 ft-lbs, instead of the correct 26 ft-lbs. That was 3 years ago and I'm not even sure that guide is still around.
Not sure what might have caused yours, if this is indeed what happened. In my case, I used an online install guide that listed the torque spec for those bolts at 18 ft-lbs, instead of the correct 26 ft-lbs. That was 3 years ago and I'm not even sure that guide is still around.
That was on ordeal
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Originally Posted by CANNIBAL
Thanks for clarifying, Andy.
That was on ordeal
That was on ordeal
I also had codes thrown that indicated a problem with my cam position sensor during my ordeal. I actually bought a new sensor and it didn't solve my problems (obviously).
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Originally Posted by Go FasTA
Yep, my bolts didn't come completely out, but they had loosened up enough to allow the cam to walk backwards. There was enough play that the dowel pin (index pin) on the cam was knocked out and ended up as a chewed up chunk of metal in my oil pan. The cam walking was enough to get a lifter jammed in the lifter bore. Block was toast.
Not sure what might have caused yours, if this is indeed what happened. In my case, I used an online install guide that listed the torque spec for those bolts at 18 ft-lbs, instead of the correct 26 ft-lbs. That was 3 years ago and I'm not even sure that guide is still around.
Not sure what might have caused yours, if this is indeed what happened. In my case, I used an online install guide that listed the torque spec for those bolts at 18 ft-lbs, instead of the correct 26 ft-lbs. That was 3 years ago and I'm not even sure that guide is still around.
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Yeesh. Sorry to hear that Steve. I know the pain all too well. I just hope for your sake that the damage is limited to the cam and lifters with no damage to the block.
Also, please double check that torque spec before you reinstall. The 26 ft-lbs. is off the top of my head, and it's been a year or more since I last participated in a cam install.
Also, please double check that torque spec before you reinstall. The 26 ft-lbs. is off the top of my head, and it's been a year or more since I last participated in a cam install.
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Originally Posted by Go FasTA
Yeesh. Sorry to hear that Steve. I know the pain all too well. I just hope for your sake that the damage is limited to the cam and lifters with no damage to the block.
Also, please double check that torque spec before you reinstall. The 26 ft-lbs. is off the top of my head, and it's been a year or more since I last participated in a cam install.
Also, please double check that torque spec before you reinstall. The 26 ft-lbs. is off the top of my head, and it's been a year or more since I last participated in a cam install.