Took me 4 hours to fix a simple valve leak underwater because I forgot one basic thing

Was on a job last Tuesday at the Port of Seattle, just a routine inspection on an intake pipe. Noticed a small leak on a ball valve, figured I'd swap the O-ring and be done in 20 minutes. Took the whole thing apart, put it back together, still leaking. Did that twice more before I realized I put the O-ring in dry. No lube. Spent the first 3 hours frustrated and cold for nothing. Anyone else have a job where you skip the obvious and it costs you half the day?

3 comments

3 Comments

michaeltorres7d ago

My buddy did the same thing on a valve rebuild last month dry o-rings every time and it held fine for 6 months so maybe youre just overthinking it.

patricia_gonzalez7d ago

Oh man totally agree with you here. I rebuilt a whole air compressor system at my shop last year and I just slapped the o-rings in dry cause I was in a hurry and that thing ran like a champ for over a year before I sold it. People get way too obsessed with this stuff. Ive seen guys spend 20 minutes lubing every little ring and then the system still leaks anyway because they cross threaded a fitting or something. Half the time the grease just attracts dirt and grit and makes things worse down the line. If the o-ring is the right size and you seat it properly dry is totally fine for most applications.

murphy.aaron2h ago

Different ambient pressure at depth changes how those O rings seat compared to doing it in a shop or above water. Cold water shrinks the rubber just enough that a dry seal won't grab right, especially on a ball valve that's been cycled a few times. Lube helps the ring settle into the groove evenly under compression, not just for sliding. Nobody mentions how a few feet of hydrostatic head changes the tolerances, but that's the whole difference between a 20 minute fix and four hours underwater.