Cam installation help needed - Cam too far back in block?
05-29-2012, 12:41 PM
#1
Cam installation help needed - Cam too far back in block? Issue: Lifters are riding on the front edge of the cam lobes (see pictures). This leads me to believe the cam is too far back in the block.
When the car was running I was getting P0343 - cam position sensor high voltage. I replaced the sensor just to have the same issue. RPMs are not seen on the factory tach.
I opened the lifter valley up to find the lifters riding on the front edge of the cam lobes. I then drained all the fluids, pulled the water pump, crank pulley and timing cover to investigate. Cam bolts were tight and remained torqued like the day I installed them (car has max, 1 hr total running time since heads/cam install).
Timing chain is SLP double roller, SLP LS6 ported oil pump.
What keeps the cam from going to far back in the block? Where did I go wrong? Help please!
When the car was running I was getting P0343 - cam position sensor high voltage. I replaced the sensor just to have the same issue. RPMs are not seen on the factory tach.
I opened the lifter valley up to find the lifters riding on the front edge of the cam lobes. I then drained all the fluids, pulled the water pump, crank pulley and timing cover to investigate. Cam bolts were tight and remained torqued like the day I installed them (car has max, 1 hr total running time since heads/cam install).
Timing chain is SLP double roller, SLP LS6 ported oil pump.
What keeps the cam from going to far back in the block? Where did I go wrong? Help please!
05-30-2012, 04:25 AM
#6
Do you have any photos of the cam prior to installation where the front undercut and other machining can be examined? Can you use a mirror or light to see if the cam journals are properly aligned with the bearings? Also, in the photo it appears the cam is back from the cam plate a bit make sure to pull if forward when checking the journals.
05-30-2012, 06:43 AM
#7
Have you seen the lifters ride this far off-center before?
Thanks for all the help. Forgot to mention, I bought the cam straight from Lunati and assumed it was machined correctly from them.
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06-02-2012, 06:51 PM
#10
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The cam retainer plate keeps the cam from coming forward; the sprocket is what keeps the cam from moving backward. The retainer is sandwiched between the cam and sprocket which are held together by one or three bolts depending on the cam design (you have a 3 bolt design).
Something is preventing the cam from moving forward, are the camshaft threads clean? Is the retainer plate damaged?
With the retainer plate in place, install a sprocket bolt in the cam (don't install the sprocket). Try pulling the camshaft forward using the bolt, does the cam line up with lifters? If the cam does not move forward I would remove the cam and compare (measure) the cam snout against the stock cam.
You can install the sprocket on the stock cam and look for any difference in fitment between the two cams.
Lunati had an issue with incorrectly machined camshaft snouts and maybe you have one.
http://www.ls1gto.com/forums/showthr...=sprocket+gear
Also the torque spec's are 18ft lb not 26 like stated in the thread.
Good luck!
Something is preventing the cam from moving forward, are the camshaft threads clean? Is the retainer plate damaged?
With the retainer plate in place, install a sprocket bolt in the cam (don't install the sprocket). Try pulling the camshaft forward using the bolt, does the cam line up with lifters? If the cam does not move forward I would remove the cam and compare (measure) the cam snout against the stock cam.
You can install the sprocket on the stock cam and look for any difference in fitment between the two cams.
Lunati had an issue with incorrectly machined camshaft snouts and maybe you have one.
http://www.ls1gto.com/forums/showthr...=sprocket+gear
Also the torque spec's are 18ft lb not 26 like stated in the thread.
Good luck!
Last edited by RQSGTO; 06-02-2012 at 08:23 PM.
06-03-2012, 06:46 AM
#12
The cam retainer plate keeps the cam from coming forward; the sprocket is what keeps the cam from moving backward. The retainer is sandwiched between the cam and sprocket which are held together by one or three bolts depending on the cam design (you have a 3 bolt design).
Something is preventing the cam from moving forward, are the camshaft threads clean? Is the retainer plate damaged?
With the retainer plate in place, install a sprocket bolt in the cam (don't install the sprocket). Try pulling the camshaft forward using the bolt, does the cam line up with lifters? If the cam does not move forward I would remove the cam and compare (measure) the cam snout against the stock cam.
You can install the sprocket on the stock cam and look for any difference in fitment between the two cams.
Lunati had an issue with incorrectly machined camshaft snouts and maybe you have one.
http://www.ls1gto.com/forums/showthr...=sprocket+gear
Also the torque spec's are 18ft lb not 26 like stated in the thread.
Good luck!
Something is preventing the cam from moving forward, are the camshaft threads clean? Is the retainer plate damaged?
With the retainer plate in place, install a sprocket bolt in the cam (don't install the sprocket). Try pulling the camshaft forward using the bolt, does the cam line up with lifters? If the cam does not move forward I would remove the cam and compare (measure) the cam snout against the stock cam.
You can install the sprocket on the stock cam and look for any difference in fitment between the two cams.
Lunati had an issue with incorrectly machined camshaft snouts and maybe you have one.
http://www.ls1gto.com/forums/showthr...=sprocket+gear
Also the torque spec's are 18ft lb not 26 like stated in the thread.
Good luck!
Guess I am removing my fans and radiator again
Thanks for the replies. The cam bolts looked fine, but if I am pulling the cam then I am ordering new ARP bolts for it. This is very frustrating for me, I haven't had the car on the road in 6 years and I really thought it was ready to go.
I hope I can find the time to get it running properly before summer.
06-03-2012, 08:12 AM
#13
Before you wig out, and tear it down, call Lunati and ask if there's a way to tell if you got 1 of the questionable cams.
Also, try the checks already mentioned.
What does the back side of the gear look like? Look like it's been pulled tite to the cam?
Put a thin film of grease on the end of the cam, and around the retainer plate, re-install the gear, and see what the pattern looks like. This will confirm/deny you have one of the over sized cams.......
You don't have to strip the top side down, just back off the rockers, in order to pull the cam forward.
As mentioned, it looks to me as tho the cam is not out where it should be...
Also, try the checks already mentioned.
What does the back side of the gear look like? Look like it's been pulled tite to the cam?
Put a thin film of grease on the end of the cam, and around the retainer plate, re-install the gear, and see what the pattern looks like. This will confirm/deny you have one of the over sized cams.......
You don't have to strip the top side down, just back off the rockers, in order to pull the cam forward.
As mentioned, it looks to me as tho the cam is not out where it should be...
06-03-2012, 08:42 AM
#14
Before you wig out, and tear it down, call Lunati and ask if there's a way to tell if you got 1 of the questionable cams.
Also, try the checks already mentioned.
What does the back side of the gear look like? Look like it's been pulled tite to the cam?
Put a thin film of grease on the end of the cam, and around the retainer plate, re-install the gear, and see what the pattern looks like. This will confirm/deny you have one of the over sized cams.......
You don't have to strip the top side down, just back off the rockers, in order to pull the cam forward.
As mentioned, it looks to me as tho the cam is not out where it should be...
Also, try the checks already mentioned.
What does the back side of the gear look like? Look like it's been pulled tite to the cam?
Put a thin film of grease on the end of the cam, and around the retainer plate, re-install the gear, and see what the pattern looks like. This will confirm/deny you have one of the over sized cams.......
You don't have to strip the top side down, just back off the rockers, in order to pull the cam forward.
As mentioned, it looks to me as tho the cam is not out where it should be...
