[romanlynch]

I haven't been able to put a lot of time in this pimp I recently got. I thought one of the barbs was leaking since the little oring was torn but it turns out the noid is leaking from the relief hole (I assume that's that this is). Does this just mean the lpr is to high or could there be another issue?

Red circle is where the leak is

[RedJin]

That is an older SMC noid. I do not believe they had pressure relief built in like Humphreys but I could be wrong. I'd take it apart and have a look at the spool to see if any of the orings/seals are bad. Worst case, it looks like you can still buy them from SMC for not a bad price. https://www.smcpneumatics.com/SYJ3120-SG-M3.html

[cyberpyr8]

It can bleed off if the LPR isn't right. We have had this before and I thought I had a blown solenoid. Lower the LPR pressure some to see if that fixes it. If it continues to leak it could be blown.

[romanlynch]

Got some motivation to look at this again. It's actually leaking from between the 2 halves of the noid right below my red circle. I figured out that the lpr pressure was at 170-200 so I'm guessing that's why it was leaking there. I assumed the hpr was CCW to lower pressure when in fact it's opposite. I got the lpr turned out pretty far and 0'ed the hpr, aired up and increased hpr till the lpr was ~130ish and it doesn't leak from the noid anymore.

The marker isn't cocked though, I think I may have the rear hoses wrong. Can anyone confirm which of the 2 rear hoses go in the "A" and "B"?

[Mr. Charlie]

Looks like the Macroline is crossed...

Try switching them.

[romanlynch]

Okay.

What is the relationship between the hpr pressure and the lpr perssure? What I mean by that is, shouldn't the lpr stay the same pressure regardless of how I adjust the hpr or is this just coincidental that when I adjusted the hpr the lpr went up?

[Mr. Charlie]

It should stay the same...

[romanlynch]

The seller said he got a brand new lpr (I received 2 of them with the marker) so I assume the one that is on it is brand new. What would cause the lpr to raise with the hpr? an oring or reg seat?