help wanted on sipmate air compressor

[andys-shogun]

hi everyone, im andy. ive just joined this site after looking at forums to try and find the answer to why my sip airmate ts 3.0 hp air compressor wont turn off. then after joining i see its a mig welding site. still maybe someone will help me. the air builds up till the guage goes into the red, and the safety valve blows off. and thats how it keeps going. i bought this second hand a few weeks ago, and have only found this fault today i only payed £50 for it so i still pleased. i will be doing some welding early next year on my old landrover, so i will be looking over this site for tips ect. i like some of the things on here, nice pics and well written. cheers andy.

 

[rtbcomp]

Most likely the pressure switch, it may be over adjusted or the diaphragm may be punctured.

Does the knob on the pressure switch work? When you switch it off with the knob does the motor stop and do you get a loud hiss for about a second whilst the delivery pipe de-pressurises?

With the motor stopped can you hear a constant hiss from the pressure switch?

If you open the switch you'll see a spring with a nut or screw in its centre, slacken this screw to decrease the cut-off pressure.

 

[pedrobedro]

Have you tried adjusting the cut off pressure. In the black box with the red knob where you switch it on there is a screw to alter the cut out/in range. Try screwing it in or out from where it is now and see if it makes any difference.

 

[andys-shogun]

yes the red switch does stop and start it ok. i cant remember if there was a hiss when it stopped though. there are no air leaks when not running. i will have a look at it tomorrow and try to adjust the pressure switch. i will let you know what happens. many thanks for your replys. andy.

 

[rtbcomp]

You may not hear a leak from the diaphragm with the unit running.

 

[andys-shogun]

were is the diaphragm? i have the instruction booklet, but they dont tell you much, as they dont want anyone messing around with the said item. it does say to remove the non return valve and check it, and i will. i bought it off a woman whose husband died a few years ago. when i tryed it in her garage i found air coming out of the non ajustable air outlet. i did not know at the time that it shuts off just by pushing the collar along the shaft. her husband must of set it to leak air because the motor would not shut off.

 

[rtbcomp]

Have a look here http://www.mig-welding.co.uk/forum/album.php?albumid=900

There's some pics of a typical pressure switch in bits.

 

[andys-shogun]

very helpful, and many thanks.

 

[andys-shogun]

all sorted now, and many thanks for all the help. i took the switch cover off, and found a 10mm ajusting bolt with a + & - sign. i gave it a turn and the motor stopped ok. a squirt of wd40 and i returned the bolt to were its always been. i think the problem was mainly due to lack of use. cheers andy.

 

[rtbcomp]

Good one, that's saved a bit of cash.