Leaking torch

[scotto75]

Hi,

I've got a Sureweld Monomig 101 that has a leaky torch even when the machine's not turned on. As soon as you press the trigger, the gas comes out the nozzle and with the regulator opened to full I can get 10l/m on the peashooter. But as soon as you let go of the trigger, I can hear the gas coming out of the torch.

I have opened up the torch and turned the regulator on full and can feel the sound of the gas leak change as I put my hand over where the pipe connects to the white solenoid housing, so I assume the pipe connection's loose, as opposed to the solenoid pin stuck, etc, especially as the solenoid appears to be working fine when the trigger is pressed.

My question is whether anyone has had experience of dismantling a torch like this and if it is possible to fix the loose pipe connection, assuming that my diagnosis is correct?

Any advice much appreciated!

 

[the snooper]

if the gas is leaking when the power is off you don't have a solenoid, it will be a valve in the torch, if you want to see where its leaking from use a brush and some soapy water around the joints , if its the gas pipe they are usually just a push fit, looking at yours it looks bodged with hot melt glue or similar

 

[scotto75]

Yeah, hot glue gun screams bodge job.

I have only just acquired it so, I will open it up tonight and see exactly what the state of play is, but if the PTFE tape on the cheap regulator is anything to go by, I reckon it's been 'fixed' before and I may not be able to remedy it.

 

[the snooper]

you may be able to dismantle the gas vale and fit new O rings if ther a leaking but the gas tubing is usually a push fit into a special fitting

 

[mike 109444]

IF you can remove the pipe and IF the fitting can be unscrewed and IF the thread in the white housing is still good then you should be able to get a better quality fitting and if you can tease the tube through the torch to gain say maybe 10mm then you could trim the end of tube and have a fresh end to push into the new fitting. The end that screws into the white housing should have an 1/8 BSP thread (or metric of similar size) If you get stuck for fitting I should have one kicking around as they are used on part of the kit I work on and are a pain in the ar55 to get a nice seal on (we look for < 10Mbar of loss at 250Mbar)

 

[mike 109444]

ps if you did not already know, you don't just pull the pipe out. You have to push a collar/ring up first to release the grip on the pipe, then pill pipe (should not need to much pull to remove)

 

[scotto75]

Thanks Mike. Unfortunately the fitting doesn't seem to be unscrewable. The verdict from Sureweld, weldequip and Lindsay, who stock Sureweld, is to get a new torch or save the money and get a new machine

 

[PTvor]

Thanks Mike. Unfortunately the fitting doesn't seem to be unscrewable.

Can't you bodge it with a bit of Bostik or something?

The verdict from Sureweld, weldequip and Lindsay, who stock Sureweld, is to get a new torch or save the money and get a new machine

I didn't like to say that, but that was my initial thought. New valve, about £20 pr new torch and lead, which might be pain for all sorts of reasons, about £30. Still, it can be amazing what turns up on ebay.

 

[scotto75]

Ha! I put some epoxy round it last and will see if it leaks now