The brass nut from the Spraying Systems Series 31 valve assembly.
Fitment
- Spraying Systems Series 31 valves (31 GunJet / AA31)
Where it sits in the assembly
Part of the same serviceable group as the shut-off disk and the lock nut. Brass is chosen here because it will not seize against the body the way a steel fastener does in a wet chemical environment — but it is also soft, which is why it is the part that gets damaged when someone reaches for pliers.
Hand tight, then a nip
Over-tightening a brass nut distorts the thread and the seal behind it. If the valve needs to be forced to stop leaking, the disk is the problem, not the nut.
Specifications
| Brand | Spraying Systems Co. (TeeJet) |
|---|---|
| Manufacturer part number | CP9036 — sold by US distributors as "Brass Nut for AA31 Series" |
| Material | Brass |
| Suits | Spraying Systems Series 31 valve |
| Thread size | Not published — ask us |
| CCW SKU | AGSCP9036 |
About the Series 31 Valve
The 31 GunJet is Spraying Systems' brass trigger valve. Spraying Systems rates the AA31 at 500 psi (35 bar) and 5 gpm (19 L/min). US distributors list it with a 1/4 in inlet, a TeeJet cap outlet, a Teflon valve seat and packing and a stainless steel stem. Know which model you have before ordering parts — Spraying Systems' own listing gives a male 1/4 in NPS inlet while some distributors list a 1/4 in female NPT version.
Series 31 Repair Parts at CCW
| Part | Spraying Systems no. | CCW listing |
|---|---|---|
| Brass nut | CP9036 | This part |
| Lock nut | CP9035 | Nut Lock Series 31 Valve |
| Shut-off disk | Not confirmed | Shut Off Disk for Metal Gun or Series 31 Valve |
Frequently Asked Questions
My valve still drips after a new nut.
The nut holds the assembly; it does not seal the flow. A drip with the trigger released is almost always the shut-off disk, or grit on its seat.
Can I use a steel nut instead?
Fit the brass part. It matches the valve's brass body, and a dissimilar fastener in a wet chemical environment is more likely to seize.
Which spray guns use the Series 31 valve?
Tell us the make and model of your gun or sprayer and we will confirm. The shut-off disk is shared with CCW's metal GunJet (NA0820); whether this nut also fits that gun is not confirmed.
Related Products
- Nut Lock Series 31 Valve
- Shut Off Disk for Metal Gun or Series 31 Valve
- GunJet Metal with Viton Packing
Tell us the gun or valve you are repairing and we will confirm the part before you order.
