have i broke my compressor

[beefertoo]

newby with question,help please.

after i broke the drain valve on my compressor, belt driven airmaster 150l (i think) i took the pump and motor off to turn the tank over and replaced the drain valve. didnt disconnect the electrics from the switch etc.

now when i've put it all back together it only gets to around 45psi on the switch gauge before it really slows the motor down (3hp single phase) but was ok before

have i done something wrong or has the motor decided to give up now??

thanks craig

 

[rtbcomp]

Check the belt tension, I had exactly the same problem when I replaced the drain cock on mine.

Also check the pressure gauge is accurate and the switch settings haven't shifted.

Also some gunge may have shifted and it's somehow obstructing the non-return valve on the delivery pipe.

 

[beefertoo]

thanks a lot,saved me buying a new one. turns out it was the belt tension and thinking about it again it makes sense. more pressure=harder to turn and more chance of slipping the belt.
now i've got to strip/clean or replace the switch....it go's up to and beyond 120psi when it used to shut off..

cheers craig

 

[rtbcomp]

That's good!

You can adjust the switch - there is most likely a heavy spring with a threaded rod down the middle with a nut on it. Tighten the nut to increase cut-off pressure, slacken to reduce.

For some reason some manufacturers state you must only adjust the nut with the tank under pressure.

Some switches have another screw to adjust the difference between cut-in and cut-out.