valvetrain just started making noise

[Chameleon]

My engine is a 440 with a Comp Cams hydraulic roller(XR286HR-10), their roller lifters, 440 Source heads, stock except for 10 degree locks, Crane 1.6 roller rockers and Smith pushrods, 10:1's. Last night I started the car and immediately could hear a difference in the valve train that I have not heard before. The engine was assembled in 2009 and installed in 2012 and has seen light duty since, Last weekend I took it out and probably put 30 or 40 miles on it around town and didn't hear anything unusual. The only thing I have done differently is starting using avgas LL100 from an airport close to my house. Listening with a stethoscope, it sounds like a lifter near #6 or #8. With the engine off, I can spin the pushrods with a slight friction and no movement up or down. Since these are hydraulic lifters, how should I check/set the preload?

 

[IQ52]

Here I am, standing beside myself............

[ame]http://www.cranecams.com/pdf-tech-tips/hydro-lift.pdf[/ame]

http://freeasestudyguides.com/hydraulic-lifter-preload.html

As you state you are using Comp Cams hydraulic roller lifters, which are part number 8921-16, here are the instructions for those lifters.

[ame]http://www.compcams.com/Technical/Instructions/Files/COMP4-115.pdf[/ame]

 

[Chameleon]

Thanks for all of the info. I will check each cylinder today and see if any are out of adjustment.

Bill