The Graco Fusion AP spray foam gun is one of the most widely used guns in the global industry — known for durability and performance. But like any high-use equipment, it requires proper maintenance to avoid costly downtime and getting help to fix the problem rather than just keep buying parts is what we do at SPF Depot.
This guide covers the most common problems contractors face and how to fix them fast using the right replacement parts and it applies to any gun you may be using. They all have the same issues at some point. The biggest issue is how to properly clean your gun along with proper shut down procedures.
Common Symptoms:
- Reduced material flow on one side
- Uneven spray pattern "C" shaped
- Pressure imbalance
Cause:
Debris buildup in the main port of the chamber. Very common on closed cell foam. Use a drill bit to clean it, but bits easily break. Thats why we sell the tip cleaner SPF-TC101. It has all sizes in one kit that easily slips into your pocket. Can be used on all ports (side and main) in the AR2020 to AR7070. AND they don't break. Its actually a tip cleaner for a cutting torch.
99.9%, the O-ring is NOT your issue for spray patterns. Stop replacing all the o-rings every time you have a problem like I did when I first started. Many times I wouldn't get any flow from 1 side and all it was is the side port on the chamber was plugged up. I wasted $100's of dollars my first year.
For flow issues, check the Wye strainer where the line comes in from the drum. Again, the "A" or ISO side is always the issue. If the foam makes "marshmallow" texture and doesn't harden, its starved for ISO. If it comes out brown and crusty its starved for Poly "B" side.
I did have one system where I took the manifold block off the Reactor and cleaned all internals. Ut was plugged up pretty well in the "A" side. Replace all the ISO fittings and use SPF ISO Solvent to clean it. Use proper size drill bits to help break it up as well as re-tap/chase the threads to clean them all.
Don't forget to check the filter screen on the check valves. The screens come in 40, 60 and 80 mesh size. Bigger the number, the finer the mesh. 80 seems to be the standard, but I always use 60. Anything that passes a 60 mesh at 1200PSI is going to pass through the chamber.
On a few occasions it would be the pump is worn out but those are very rare. Graco pumps are well built. At most, you can buy a seal kit to replace the seals. If the pump is leaking at the rod end, its the white PTFE seal (rod scrapper) that is bad, We sell those separately if needed. Go to SPFDepot.com and in the search block enter ROD SEAL and you will see them all. Thats caused from the TSL fluid not pumping. If your TSL bottle looks like a milk shake, replace the fluid and flush the lines, TSL pump and the TSL check valves in the bottle with WD40. We do have a seal kit for the TSL pump thats much cheaper than buying a new TSL pump - to view them, enter TSL SEALS in the search block.