La San Marco 85 Mod 2 Pump Troubleshooting

Equipment doesn't work? Troubleshooting? If you're handy, members can help.

#1: Post by hosso22 »

I have a La San Marco 85 Mod 2. The external rotary pump went out recently (it was quite old) and I bought a new one with a new vane as well.

Before replacing my old pump I tested the new vane and motor. Vane spun without issue and motor started right up.

After hooking up to the espresso machine I notice that the pump is struggling to reach 9 bars. The motor feels under powered, despite having the same specs as my old motor. For the most part when I engage one or both of the groups the pump will work if I have loosened the pressure bolt all the way but as soon as I increase the pressure the motor begins to struggle.

Any ideas as to what could cause low power? Is the manometer (which is also new) waaay off? Any guidance would be appreciated. Thanks