K5 unloader leaking

So this has happened to me a couple of times: the unloader will leak from the adjustment screw, to varying degrees depending on whether I’m pulling the trigger or not. I pulled it apart at one point and replaced the seal with one from my older spare k5. That fixed the problem completely for a week or two, and then atarted up leaking again.

Does anyone know where/ what size seals to get for this? And what type of grease should I be using when rebuilding these? I think I made the mistake of putting it together dry the last time.

The rebuild kits are ridiculous

They should not be rebuilt. Once it needs a rebuild you’re close to wearing out the orifice unless you stepped down a size and wear into it so by that time you’ve really got into the brass. They go in the trash at that point. Yes you can rebuild them with a new kit but what about the brass orifice? Like I said pitch it in the trash.

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I guess I’m still not totally understanding how these things work. Are you speaking of the orifice on the bypass side, that provides the appropriate back pressure to avoid the “kick”? The k5 is built a little differently than the k7. I had to make my own orifice out of a 1/2” hex plug and drilled like a 5/32” hole in it.

The amount of hours on this unloader, I have a hard time imagining that that orifice is already wearing out, and if it were, it would be a $1.50 fix.

Or is there a different orifice you’re talking about?

At any rate, I understand that it’s probably best practice to replace these when they start leaking, but I believe I caused premature failure of the seals by abusing it with undersized tips on a surface cleaner. It was cycling the pressure/bypass horribly.

Sorry, what did you drill the 5/32 hole for? Was it surging? The orifice I’m speaking of is on the high pressure outlet. The .1 .2 .3 part of the part number is in reference to the hole size (only part that changes between the different model numbers) on the high pressure outlet side. The restriction you created on the bypass orifice helps with the pressure balance for a smoother operation.

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@Infinity I lube the ptfe rings about every 2 months with a water resistant marine grease.

The compression rings are part # 92772200 There are four total.