Masport M2

[Allstar Sanitation]

I have a Masport M2 connected to a 150 gallon waste tank for our very small pump truck. But it doesnt suck anywhere near the sucking power of the other pump trucks we have.

Setup is as follows:
Waste tank > hose > Pump > Exaust (very simple)

Symptoms include:
Doesnt hold vacuum
A hiss sound after the pump is stopped (connected?)
Lack of vacuum, we can put our gloved hand over the suck hose and it is easy to remove, doesnt try to eat it.

We have a 20ft hose on the end if that helps solve this situation.

I took out the pump vanes and replaced them all cleaned out the unit and put it back in, should there be any seals on the end plate?

[VacuumEngineer]

I dont have much experience with those little guys but the hissing, as you probably know, is a leak somewhere. I would imagine there needs to be seals on the end plates, metal to metal isnt the best seal for vacuum.

Contact - customerservice@masportpump.com Theyre always more than helpful.

[JoshMD]

Could the hissing be coming from your vacuum relief valve being set to low or malfunctioning.

[KPToilets]

It could be a check valve stuck open, a leak, and a dirty pump.