89 mid cabin bad valve lifter noise

[mrrudely]

the boat has twin 454's
port engine developed what seems to be a lifter noise
mechanic did a compression check and found number 8 at 50psi
all the rest were good
he thinks burned valve because of bad gas
we bought the boat after it had been sitting for at least 5 years
did compression check then and all cylinders were good
pumped some old gas out day one and have since put some fresh gas in so whatever was old had been diluted
we have put less than 100 hours since purchase
any thoughts?
lifter noise just a coincidence or result of a sticking valve?
thx

[prowlersfish]

Sticky valve , bent push rod or broken spring come to mind .

[mikeandanne]

Have your mechanic do a proper leak down test on #8, that will tell you what is leaking.

[mrrudely]

can bad gas burn up a valve in less than 30 hrs?

[prowlersfish]

Not likely . Under High load , running lean maybe . A valve that slightly leaks can burn . A slightly sticking valve , a weak or broken spring can cause a valve leak then burn .

[mrrudely]

turns out to be a stuck valve in #8
causing a bent push rod

[prowlersfish]

Thanks for the update . Glad you found the issue .