noisy valve train?

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spooled scamp

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71 318, has 340 heads on it with oversized valves. i cant remember any of the sizes or numbers i put this together over ten years ago and drove it ten miles and have ran it a couple times over the years just at the house. the valve train has some noise. all new lifters, push rods, i THINK the cam is a .488/.488 if i remember correctly. nothing horrendous sounding but does make some racket, almost sounds like a solid lifter car. the rockers are stock non adjustable, i had bought a set of steel adjustables, never put them on the car, i am thinking this should solve the noise, that the stock non adjustable lifters and size of the cam are fighting a bit with the lifters and thats the clacking noise? car runs real good just some noise. i know those non adjustables have to go and arent helping. anyone have this issue? have to figure out what lash to set on this also. thanks.
 
I'd run it for a while as it is,, the noise will likely go away,, an oil change and additive may be in order.. jmo

hope it helps
 
spooled scamp said:
71 318, has 340 heads on it with oversized valves. i cant remember any of the sizes or numbers i put this together over ten years ago and drove it ten miles and have ran it a couple times over the years just at the house. the valve train has some noise. all new lifters, push rods, i THINK the cam is a .488/.488 if i remember correctly. nothing horrendous sounding but does make some racket, almost sounds like a solid lifter car. the rockers are stock non adjustable, i had bought a set of steel adjustables, never put them on the car, i am thinking this should solve the noise, that the stock non adjustable lifters and size of the cam are fighting a bit with the lifters and thats the clacking noise? car runs real good just some noise. i know those non adjustables have to go and arent helping. anyone have this issue? have to figure out what lash to set on this also. thanks.
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That's OK, don't stress. Does the noise go away, when it warms up? Sure sounds like lack of lifter preloaded. This happens with aftermarket camshafts(to get the lift cheaply, they grind deeper in the base circle, compared to stock grinds.),& valve jobs,raise the valve spring installed heights.
I would let it run a while, possibly try a bit of ATF to loosen things up first. That would be my first moves, the first comment, would be near the end.
 
318 rocker arms are different from 340 arms. 340arms are cut for clearance to the larger springs and retainers. I believe its possible that 318 arms on 340 springs can **** the retainers enough to spit out the keepers. If that happened, the valves can drop into the cylinders with resultant catastrophic failure. You might want to check that clearance, before you;" run it a while as is", or "let it run a while".
 
thanks. thats why i bought the adjustable rocker arms. this cam and heads ran fine in a 340 with no noise. i have to pull the rocker shaft and look for wear, no matter what i am putting the adjustables on. i think the non adjustables just cant handle the lift from the cam. i dont think this is a regular noise that should be there. the valve covers are stock, so my other thought was maybe its ticking the inside. i had kids and this project came to an abrupt hault over ten years ago like i said so now just getting back into it. i will pull and check all the pushrods also to make sure nothing got bent. no need for catastrophic failure at this point i need to daily drive this car for a while until i can fix my truck.
 
well pulled the driver side valve cover, lots of lateral play in the rockers, otherwise things look good. the steel valve covers are going though, lots of hidden rust from condensation up by the pcv valve, it fell into the head, luckily was some chunks so easily out but am throwing some magnets on the engine to grab any of that crap and aluminum valvecovers. i looked at the adjustable set i have, they have springs on the shaft to keep that lateral play away. now gotta install and adjust.
 
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