360 valve,rocker noise question.

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chrisd6875

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Hi all,
I just started my LA 360 on Friday to break the cam in and have a fairly loud knocking sound from the passenger side. I bought this engine a few years ago and replaced mostly everything except the pistons, rings and crank. I had the heads redone, and installed a Cam/Lifter kit.
I removed the valve cover on that side and found that some of the rockers are not tight. I'm not sure if they should always have tension on them? I do remember when I installed the rocker assembly on that side that some of the rocker were loose, especially one which has more than a 16th of play between the push rod and the rocker. They guy who guided me with the cam break-in, said that it might tighten up after the lifters fill up. I changed the oil after the break-in, and ran it again with no improvement.
After I took the cover off I removed the rocker assembly to see what was going on. I measured the push rods and the rocker and then noticed the valve stem tops were all a bit different, one is lower by a good 16th of an inch. Is this normal? A few more by about a 32nd. Could this be the source of the knocking? The push rods are original as is the rocker assembly. Rocker assemblies were torqued down properly, also had plenty of oil up on top of the rockers and springs. The heads are 360 heads, I supplied the springs they are comp cam 901-16. The cam/lifter kit is Lunati 10200701LK.
 

for starters are the rocker shafts on the correct sides and turned the right way and if the heads were redone and the valves are at different installed heights that's not good. was it a professional shop that rebuilt your heads?
 
I thought I was told that the rocker shafts can go on either side as long as the oil holes are pointing down?
Yes, I had these heads done at a professional engine shop. He cleaned up the valves/seats, took off .020 and installed my springs.
 
the notch in the shaft goes down and towards the back of engine on the paaaenger side and down towards the front on the drivers side .
 
Ok just checked, I had that right.
Just found a thread here about this issue. One solution was to use lash caps. I will check into this. Just took the driver side apart and the valve stems are uneven there as well. The rockers on that side are not loose though. I am also going to check the push rods for straightness tomorrow. It was knocking pretty good.
 
can you take a pic or 2 lay a straight edge across the valve stems and snap a pic . lash caps wont fix shitty machine work and that's what I understand is going on. the valves need to be be the same height this is not a sm block chivvy .
 
Could the lifters not be pumping up for some reason? Is you oil pressure good, maybe a little bit of assembly lube got somewhere it shouldn't and are limiting the oil from getting to the lifters. Just thinking out loud.
 
Oil pressure was about 75 when we primed the pump by hand. Now while its running, it is at 55 psi. I have Lucas 10-40 high zinc installed. The lifters were new and not pre-soaked.
 
Oil pressure is fine, exactly what I have in mine. I never pre-soaked mine, just primed it like you did. Seems like the valve stems were an issue. With non-adjustable rocker gear some can be loose depending on the stem height.
 
can you take a pic or 2 lay a straight edge across the valve stems and snap a pic . lash caps wont fix shitty machine work and that's what I understand is going on. the valves need to be be the same height this is not a sm block chivvy .

Sounds like a Chevy shop did them and didn't set stem height.
 
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