Airco heliwelder IV troubleshooting

[Rockomuchaco]

Until recently this machine has run great! Now, any time I depress the foot pedal it welds wide open on whichever setting I'm on (course adjustment--low, med or high & weld output 0-100) any ideas as to why I can't control amps? I don't have a manual for this welder. Any help is appreciated

[H80N]

Until recently this machine has run great! Now, any time I depress the foot pedal it welds wide open on whichever setting I'm on (course adjustment--low, med or high & weld output 0-100) any ideas as to why I can't control amps? I don't have a manual for this welder. Any help is appreciated

if you post a pic of the front view of the machine and give us a serial number... we might be able to figure it out a little better... many Airco machines were just orange Millers....

But you have not given us much to work with...

[turbo38t]

Like the dialarc HF....possibly something stuck in the footpedal? Does the thing strike an arc if you touch the tunghsten? Assuming the high frequency switch is working in the foot pedal?

[Rockomuchaco]

Here's the S/N--MH202134. I have a pic of the front panel, but it's on my phone and don't know how to post. Welder doesn't scratch start. It'll start with pedal, just have no adjustability with it. Current setting on machine--Contactor-remoteCurrent- remoteWeld current -70HF-startCoarse setting--med (17-140A)DCSP

[H80N]

I have a pic of the front panel, but it's on my phone and don't know how to post.

how about emailing it to yourself then saving it??

[Rockomuchaco]

here's a pic of the front

[H80N]

It looks very much like an "Aircrafter".... take a look at this manual and see how that matches up...

http://www.millerwelds.com/om/o351h_mil.pdf

[Burnt hands]

Rockomuchaco

Here is schematic of my machine which I believe is same as yours.

If it helps, I can mail you a copy of the instruction manual.
It's 35 pages and I only have a paper copy and not in electronic form.
PM me with a mailing address if you want it.

good luck,

[CharleyL]

The first thing that I would do is take apart the pedal. Make sure that the wiring inside isn't broken, especially the ones connecting to the potentiometer. Also use an ohmmeter to check the continuity of the cables back to the plug on the welder. The pedal and cable(s) take take quite a beating and are frequently the source of problems like this.

Charley

[Rockomuchaco]

thanks for the tips! gonna tear into it this weekend.

Rocky

[Lila Teixeira]

Heliwelder

Rockomuchaco

Here is schematic of my machine which I believe is same as yours.

If it helps, I can mail you a copy of the instruction manual.
It's 35 pages and I only have a paper copy and not in electronic form.
PM me with a mailing address if you want it.

good luck,

Tenemos una Airco Heliwelder IV, code: 0920, serial: 11R2348C y necesitamos el manual, podrian enviarlo por favor al mail [email protected]. gracias.

[Rockomuchaco]

gotta bring this back up. Thought I had it fixed, but it is down again. This time took it to LWS and they diagnosed it as having a bad control board. Unfortunately, the welder is obsolete. Is there anywhere I could search or send it(board) to and have rebuilt, repaired? Thanks, Rocky