So today I pulled the valve covers off to check valve clearance and polish my covers I noticed a looks to be washer and some shavings on the magnets I have in my heads and on the other side a real fine spring with further investigation goes to a valve seal so what now motor runs great  I pulled off my stud girdle and inspected all my roller rockers and was able to get a better look at the failed valve seal and notice the other valve seal same cylinder was not seated as well  question should I replace the two can I do it with the heads  on the boat or just run it . I pulled the plug on that cylinder and looks clean like the rest   And my next question is some of the valves were a little loose motor only has maybe 10 hrs on it and 2 oil changes since built motor specs are 496 stoker solid flat tappet lifters crane roller rockers clay smith cam  cam specs are duration @0.50 264* .630 lift and valve adjust at .024 both intake and ext is it common for the valve to loosen up a bit  and to clear things up motor runs great mid 80's all day long just was wanting to do a little up keep


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Yes, you can do all of that without pulling the head.  You will want to rotate the engine so that both valves on said cylinder are closed, then pull the rockers and push rods.

Next, you will need to pressurize the cylinder so the valves don't fall in.  You can either use a leak-down tester, some compression test gauges have a removable hose that you might be able to find a matching quick-disconnect for your air compressor hose, or you could make your own tool inserting a quick-disconnect fitting into a spark plug non-fouler adapter http://m.napaonline.com/parts/PartsDetail.aspx?k=NDP7302444_0375753199 or even an old spark plug body with the ceramic removed.

The LSM valve spring compressor http://m.summitracing.com/parts/lsm-sc-800 is the best I have used, I highly recommend it for what we do.  And it can be adapted to any head.

I would also recommend figuring out why the failure occurred.  Sounds a little like interference with the retainer.  You should have a minimum of .060 between the valve seal and the retainer.

Good luck,

Joe

so I pulled my girdle off both sides and removed all my roller rockers and inspected them all and noticed a couple more not seated where they belong all on the same head pulled some plugs on the same side to see if burning oil and there clean as a whistle re set my valves to 0.24 and put it back together-what harm  would it do to run it as is for a few more trips 


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