PM7 leak in front of noid

[deadmeat3344]

PM7 leak in front of noid (around eye ribbon holes). Facebook crosspost





Hello all,
I am fighting a frustrating leak with a PM7 where it leaks around the eye ribbon channels (with the frame off of course). Best I can describe the location. Does not appear to leak out of the blocked off air passage screw that's there.
VID LINKED BELOW:
https://www.youtube.com/watch?v=o0KatrGfABE
Some notes:

1. Bolt is a rebuilt DM10 bwing bolt with the Pm7 front can (issue persists with stock bolt setup as a note). 017/70 was added on the back cap to position the bolt properly in the breach. Soft tip is a new M2 soft tip
2. I am using the new retrofit noid body with the original noid mounting screws (screws that came with new spool did not tighten the noid down at all). Pilot is new as well. I have the same issue with the original noid.
3. Dwell is at 18ms
4. HPR is around 240 PSI which gets me a solid 335 fps using reballs with a .675 PWR insert, perfect bore match (which should be close to 300 with real paint) . HPR is a rebuilt PE sl3 (issue persists with other hprs). I did try resetting this (starting at 130 and working my way up) and arrived at that pressure every time. Leak persists regardless of HPR pressure
5. LPR is rebuilt MINUS the seat (waiting on that). existing seat did not look great but i flipped to the better looking side. LPR body orings have been upsized to 013/70. I did try 014/70 with no change. Have not tried anything 90 duro. New LPR seat arrives tomorrow which I will also try. The 006 UR90 was also replaced.
6. I've replaced the bolt sail oring , the 017 positions and the 013 in the top hat with no change.
7. ****Leak stops if LPR pressure is set low enough for bolt to be stuck forward.***
8. Output pressure on my tank is 450 PSI

Please advise, thanks!

[Trbo323]

[*]HPR is around 240 PSI which gets me a solid 335 fps using reballs (which should be close to 300 with real paint) .

Paint is faster than reball because reballs are made really small. On average paint is 10fps faster. You might just be overpressure

[*]LPR is rebuilt MINUS the seat (waiting on that). existing seat did not look great but i flipped to the better looking side. LPR body orings have been upsized to 013/70. I did try 014/70 with no change. Have not tried anything 90 duro. New LPR seat arrives tomorrow which I will also try. The 006 UR90 was also replaced.[*]I've replaced the bolt sail oring , the 017 positions and the 013 in the top hat with no change.[*]****Leak stops if LPR pressure is set low enough for bolt to be stuck forward.***[*]Output pressure on my tank is 450 PSI[/LIST]Please advise, thanks!

This sounds like an LPR issue. I think what's happening is HPR air is bypassing the LPR all together so you are feeding the noid 400ish psi. It's not a leak it's venting the over pressure. When you shut the LPR it still seals enough for that but as soon as you open it there is straight HPR air coming through.

Post a picture of the LPR, maybe with measurements, I've had a dye/proto LPR kicking around in my toolbox for a while, I can check and see if it is the same one for you.

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[deadmeat3344]

As a note, I'm shooting the reball with a .675 insert that's a perfect bore match.When I tested weights reball was quite a bit lighter vs my test paint (where its basically right at 300 fps at this given pressure). The leak occurs regardless of HPR pressure, even at 130 psi. How would I be feeding the noid 400 psi??

What measurements are you looking for on the LPR?

Also as a note I am waiting on a new LPR seat which arrives tomorrow. So my if seat is bad and causing the LPR to overpressure the noid that would make sense.

[Trbo323]

As a note, I'm shooting the reball with a .675 insert that's a perfect bore match.When I tested weights reball was quite a bit lighter vs my test paint (where its basically right at 300 fps at this given pressure). The leak occurs regardless of HPR pressure, even at 130 psi. How would I be feeding the noid 400 psi??
.

That was a typo, I meant the 240psi you mentioned earlier

.

What measurements are you looking for on the LPR?.

Diameter and length, a photo would help as well

.

Also as a note I am waiting on a new LPR seat which arrives tomorrow. So my if seat is bad and causing the LPR to overpressure the noid that would make sense.

Yeah if it's anything simple I would hope the seat would be it. It could easily be causing what you are seeing.

A few other things that could cause it,

#13 interior top hat 013
#8 outer sleeve, the second ring from the front 020
The rear most outer body o ring on the LPR (very low chance. I'm pretty sure this would vent from somewhere else)
Either interior o rings in the LPR

Was this marker working at any point before changing parts?

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[deadmeat3344]

When I first got the gun I put about 3 hoppers through it. Nothing more than that and it did not leak at the time (however, that was on a windy day which might have masked the leak if it was present) . The internals revealed it has not been serviced in some time. The guy I got it from claimed it was gone through in 2023 and it was clearly in need of a rebuild. LPR was very dirty, seat was shot. And it had a buna 006/70 oring inside the lpr (that the piston stem rides in) instead of the urethane 90 that was supposed to be there.

My new LPR seat comes in tomorrow, will post an update once that's done.

[Trbo323]

I have a dm6 and rebuilt the whole thing with buna, probably 5 years ago and it's still going strong, granted mine sees very little use as a loaner/backup but still. The older dye/proto stuff doesn't care what material you use. I've always had the opinion that since about 2012 dye stuff got really picky and it will absolutely matter what material you have but the older stuff is great because you can put anything in there and it will work.

I know there were a few typos in the dm6 manual for o ring sizes regarding the LPR. The outer body o rings are supposed to be a 013 and the manual says they are a 012.

I saw the pm7 manual also calls for 012 so I'm wondering if that is also a typo. You might want to try 013 and see what happens because that could cause air to bypass the LPR all together and cause your leak. I'm not sure why it would stop when you 0 out the LPR but it might be worth trying anyway

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[deadmeat3344]

I already am running 013's on the lpr body and also tried 014's with no change.

[Trbo323]

Have you tried 12? If it's not a typo then you currently have the wrong size

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[Kit352]

My pm7 was a mess after sitting in my basement for like 10 years. Captain oring kit replaced every seal and it's been fine. I didn't even use the factory manual for oring replacement, just used the included color coded chart. Zero guess work.
Sounds like you are over pressuring it at the very least. I shoot reballs at 250fps and the gun ends up being around 270 with paint so just a tweek of the lpr and I'm off.
Are you base line setting up the gun correctly? Lpr out x turns then got to get to ball park fps then lpr to suit. Some tweek for snap and other tweek for sound.

[deadmeat3344]

Have you tried 12? If it's not a typo then you currently have the wrong size

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Yea tried 012 at first per the manual.

[Boots4036]

If it’s coming from under body I’m going to say it’s a lpr pressure issue or solenoid. Lpr body orings will leak from front by lpr cap bad. Best bet try new reg seat when you get it. I’ve had newer style reg seats still fail, fyi. I’ve received newer reg seats and material is different and softer. Any chance you have a different noid to check? I’ve had old noids leak in same general area, clean lubed and fixed the issue

[deadmeat3344]

If it’s coming from under body I’m going to say it’s a lpr pressure issue or solenoid. Lpr body orings will leak from front by lpr cap bad. Best bet try new reg seat when you get it. I’ve had newer style reg seats still fail, fyi. I’ve received newer reg seats and material is different and softer. Any chance you have a different noid to check? I’ve had old noids leak in same general area, clean lubed and fixed the issue

Both my new retrofit/upgrade noid from Dye and the factory noid have the same exact leak. LPR Seat arrives tomorrow, hopefully that's it.

[deadmeat3344]

Update: with the LPR seal replaced the retrofit new noid still leaks in the same spot, but now the original noid is leak free!. HPR pressure is at 230 (which is what I needed to get 335 fps with reball on a .675 pwr insert) with the lpr just high enough to be consistent and cycle at 10bps.

130 psi on the hpr with the lpr up just enough to cycle with the new noid still leaked.

Will contact Dye on this. This noid design might simply not work with the PM7. I theorize it is too physically short to seal properly

Attached are pics showing the noid differences as well as the grease pattern on the body which might show where the leak is with the new noid.