cam installed,possible bent valves...HELP
05-22-2005, 03:52 PM
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cam installed,possible bent valves...HELP Just installed an FM14 cam in my 01 WS6,the intake valve springs on cylinders 3,4,5,6 are slightly shorter in height compared to the other springs (all are the same Manley dual springs with titanium retainers). We installed shims on all the valve springs.
Just for grins,we pulled the rockers and filled the cylinder with compressed air and tried to take off the spring and the valve is stuck on the spring. As we crank the spring down the valve stem goes down as well and we even hit the spring w/ a hammer before doing this and while its under pressure. Havent tried this on the other cylinders yet. Are these intake valves possibly bent??
The car only ran for a few seconds last night before it wouldnt start and the # 3,4,5,6,7,8 plugs were fouled and 1 and 2 were just sooted up. Got new plugs last night and put them in today,but ran into this problem before we tried to start it again.
HELP PLEASE!
Just for grins,we pulled the rockers and filled the cylinder with compressed air and tried to take off the spring and the valve is stuck on the spring. As we crank the spring down the valve stem goes down as well and we even hit the spring w/ a hammer before doing this and while its under pressure. Havent tried this on the other cylinders yet. Are these intake valves possibly bent??
The car only ran for a few seconds last night before it wouldnt start and the # 3,4,5,6,7,8 plugs were fouled and 1 and 2 were just sooted up. Got new plugs last night and put them in today,but ran into this problem before we tried to start it again.
HELP PLEASE!
05-22-2005, 04:00 PM
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Are the springs new? The might have mismatched the set.......
What kind of spring tool are you using? Sometimes the valve will push down as you compress the springs. If the heads are off the car, you can LIGHTLY tap the bottom of the valve to break free from the locks.
What kind of spring tool are you using? Sometimes the valve will push down as you compress the springs. If the heads are off the car, you can LIGHTLY tap the bottom of the valve to break free from the locks.
05-22-2005, 04:06 PM
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The springs were brand new in the box.
The spring tool we're using is an $11 from NAPA and we cut off most of the handle. Works very well actually with a water pump bolt.
The spring tool we're using is an $11 from NAPA and we cut off most of the handle. Works very well actually with a water pump bolt.
05-22-2005, 04:21 PM
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Did you hear air leaking out when you presurized the cylinders? Going by your other thread, I'd guess you installed the cam out of correct phase and bent your valves. Did you use an adjustable timing set with multiple keyways and dots on the crank gear?
05-22-2005, 04:33 PM
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Yes,there is air comin out of the intake.
The crank gear has multiple slots for the crank keyway as well,and we installed the cam with the dots lined up on the crank gear and cam gear.
The crank gear has multiple slots for the crank keyway as well,and we installed the cam with the dots lined up on the crank gear and cam gear.
05-22-2005, 06:09 PM
#7
Originally Posted by NVE THIS
The springs were brand new in the box.
The spring tool we're using is an $11 from NAPA and we cut off most of the handle. Works very well actually with a water pump bolt.
The spring tool we're using is an $11 from NAPA and we cut off most of the handle. Works very well actually with a water pump bolt.
Be careful with this, i've broken several bolts off using it..
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05-22-2005, 06:53 PM
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Will I have to fly cut the pistons with the F14 cam? I have heard that they should be fine? Also, how do I ensure the cam is timed properly? I aligned the dots on the rollmaster crank gear and the cam gear?
05-22-2005, 07:10 PM
#10
You must allways degree your cam before start up! The new GM HIGHTECH PERFORMANCE magazine has a good article on how to do this.
At least degree number 1 cylinder.
At least degree number 1 cylinder.
Last edited by gollum; 05-22-2005 at 07:21 PM.
05-22-2005, 07:13 PM
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Jeez this sounds like a cam swap from hell.... the intake springs are slightly shorter? did you measure these against ALL the springs before the install or during/after the install? The cam should not need flycutting... tapping the top of the valves with a hammer to loosen the locks is a common practice but sometimes you might have to do it more than once or the valves will compress with the springs if the locks stay in/tight no big deal, I have done over 25 cam swaps and this justs sounds a "little" like inexperience.....I am not busting ***** here but I dont think spring height is the cause of your no start problem......
05-22-2005, 07:28 PM
#12
His springs are shorter because his valves are bent and the valves are not closed. There are multiple keyways and multiple marks on the crank gear. He did not use the correct mark for the keyway used and the pistons hit the valves when he tried to start it. The cam does not HAVE to be degreed, but you need to understand how an adjustable timing set works to correctly install dot to dot.
