I'm just wondering if anyone here has had experience running a inverter TIG welder off of the 240V output of a 6/1 with an ST5 gen head (mine has an AVR)?

I ask because I have somewhat successfully run a Harbor Freight Inverter TIG welder from a 4KW Generac w/3600 rpm Briggs engine.

When I say somewhat, I mean it welded fine at a reasonably low setting (110 amps) doing just a stick job, but I was a bit nervous and turned th e welder off between short welds. Everything went well, and then I got more confident and didn't switch off. After about 5 minutes of very intermittent and short welds -- mostly positioning things, I saw and smelled some smoke coming out of the welder, and shut it down, thinking the worst.

I opened up the case and saw no blackened traces or wires, nothing obvious at all. Finally noticed what looked like maybe a huge air cooled wound power resistor or coil (not sure what it is) had a little of the varnish looking slightly different than another one, and it seemed in the position where the smoke came from, and I felt a little residual heat in the chassis there, so I guessed this might have been the cause.

I reconnected the welder to mains 240, and it started up fine and welded.

So, I'm a little hesitant to run it off of the Metro now -- although that's supposed to be one of the reasons I got it. I hate to experiment, where you find out the answer to a question by burning out a $500 welder, so I really wonder if anyone else has had experience with a welder on a Listeroid/ST5.

In trying to figure out what happened, I did try it again very briefly on the Generac. It also works there still, but I switched it off before heat could build up in that reisistor/whatever. Everything seemed cool afterward.

In reading more about 240v operation here on the Listeroid, I've started to wonder if what happened on the Generac had anything to do with voltage regulation -- maybe on one leg only?

The Generac has a 4 prong receptacle for output of 240 and split 120. The welder has a 3 prong plug and was hooked to a receptacle fed from the generator outlet and was wired with equipment ground to the ground prong, and black and red to the two hot lugs. White neutral was not connected.

I don't know how the Generac is regulated -- whether the 240 is regulated, or whether only one leg of 120 is regulated. Is it possible that I had the floating neutral problem, or that I miswired the plug and outlet, and the welder got too high or too low a voltage?

Or, is this possibly a 240V generator waveform or noise problem that the inverter welder can't cope with? And should I expect the same or worse with the Metro/6-1/ST5 head?

Thanks for your help.

re. ST5 with brushes and AVR

Hello all, it's been a long time since I've been on the forum or used my Listeroid Metro 6/1. I want to get it ready for winter and add the improvements I always wanted to do, so I checked it out in the shed where it is mounted.

A mouse had recently started a nest on top of the generator's brush terminals. I cleaned that out before trying to start and checked the brushes and terminals. They looked okay. I pulled the brushes and wiped them and the rings with a denatured alcohol moistened paper towel. The rings looked shiny and the ends of the brushes weren't cracked or broken. This is a low hours engine and genset. It doesn't look new only because there hs been some rust on the flimsy doghouse sheetmetal on top of the gen head where the thin paint cracked off. One of the things I want to do now is remove it and build a proper junction box off the generator.

Anyway, the Metro started easily, and the genset spun up and I had 120V showin on the meter with the panel switch still in the "off" position. I left the engine to warm up for aa minute to check the water lines and radiator to make sure the cooling system was working. When I got back I noticed there was no indication on the meter, and moving the switch to "on" no difference. There was no sign of electrical overheating anywhere, and there had been no electrical load on the generator since it was started.

I own a VOM, but am not quite sure where to start checking for the problem. The switch and the light are very cheesy quality, (one of the light socket contacts feels loose) and I'm wondering if that circuit is the source of the problem. The switch and light (incandescent) are in series together, and the leads that feed them go back throught the pass-through into the generator case. Thery're bundeld together with some other wires in an insulator sleeve, so I can't tell exactly where they go. Is that to the field?

So first question is, can I jumper the two leads together that go to the switch and light to bypass them?

And if that doesn't work, Is there a troubleshooting procedure of steps to test with the meter to find out where the problem is? A link is fine if there is somewhere in the forum. Or if not, can someone make suggestions?

I greatly appreciate it.!

I've got a Kill-A-Watt and have been monitoring and adjusting the Metro for 61 Hz unloaded. But I wasn't able to control the voltage with the potentiometer on the front of (what I believe is) an AVR.

My instructions say nothing about any AVR shipped with the ST-5, but there it is anyway.

I'm attaching photos of the terminals outside the doghouse and inside. I believe that AVR came connected properly for 240 V but incorrectly for 120V , but I wanted to check that out with you all.

If you look at the external terminal photo here you see a connection diagram showing where to place two jumper lugs for either 120 or 240. In the photo the lugs are on the 2 center terminals for 240 operation.



If you measured across the two outermost terminals (U1 to U2) you'd get 240V If you measured across either the right (U1 and U6) or left pair of terminals (U2 and U5) you'd get 120V.

For 120v operation the jumpers are placed on the two outer pairs of terminals, per the diagram and then you get 120 across the pairs. Basically you're paralleling output.

Now lets look inside the box.:



The AVR is the blue box on the left. On the right are the terminals. The AVR has two thin wires coming out of it that go to the bottom two terminals. One is black and one is red.

Here's a close-up:



The two thin wires are on the right, connected between U1 and U6.

As a guess, these are sensing wires that monitor the voltage, and when the generator is configured for 240V operation, these are on one leg, and will see 120V.

However, if the jumper lugs are re-configured to give 120V, U1 and U6 are tied together, and the AVR will see zero volts (I believe). And the AVR won't work. Right?

That's what I think happened in my case when I configured the genhead for 120V. Adjusting the AVR had no effect on output voltage. When I re-configured for 240 volts, the AVR adjuster worked.

So my question is, If I want to configure for 120 V, should I also reconnect the AVR leads across the 120 V output - U5 to U6?

Thanks!

ps. (U5 to U6 would seem a better choice than U1 to U2 in case it was reconfigured as 240 V without remembering to re-connect the AVR as itwas before. The AVR would see 0 volts instead of 240, which might blow it.).

Hello all,

I just ran my new Metro 6/1 yesterday and had a great time seeing it spring to life.

Unfortunately, after about 5 minutes of running, I thought I heard some "off" sounds -- a little more clackety-screechy than the first minute -- but I wasn't sure. I stopped it -- had planned to anyway at this point to change break-in oil. I drained it and cleaned out the sump. Then after checking things over to see if I could find any source of the noises by slowly rotating by hand -- nothing.

There was no casting sand in the bottom of the engine, when I first examined it, and none after the 5 minute run either. The magnet I put in looked good. Nothing I could see was causing any problems.

The water pump was leaking out of the pulley end, I figured it must be a stiff seal or packing of some kind. The engine had sat for a year in the crate and the pressure of the fan belt may have deformed the seal in one position. I hoped running might help the seal.

I started the engine again to see if the sound was still there, but I couldn't hear it. I applied some pressure to the flywheel rim with a 2 by 4 to help load the engine to set the rings. After 10 minutes more, I thought the internal mechanical noise was maybe more noticeable. Then all of a sudden it stopped and the engine suddenly ran extremely quietly and smoothly compared to how it had been before. But then I started to see smoke coming out of the lower back side of the engine. So I looked at where it seemed to be coming from. What could that be? No exhaust down there -- it couldn't be -- an exhaust leak would be up at the head. Then I saw it. The fan belt was smoking, and the water pump pulley was stopped. Must be seized.

I stopped the engine. Took off the pump. Opened it up. It had ball bearings at the pulley end of the shaft. And no bearings at all at the other end. The ball bearing had a broken inner shell -- bits of metal and ball bearings loose. It was very cruddy and rusty, with very little grease in it. What grease there was looked like something wiped off of the garage floor.

The more I looked at this pump the less I understood. How could it possibly work without a bearing at the rotor end? How could it seal at the ball bearing end without a seal there? I did find what looked like a seal at the rotor end, but the metal part of it didn't fit the shaft.

I'm completely stumped by this pump. How could it possibly work? How could the water not have flowed through the ball bearing and out that end plate (in fact it did!).

It makes no sense to me unless there's a missing bearing and seals.

Can someone else here explain?

I can post a photo of the pump parts later tonight when I figure out how to do that on this forum.

Also, I'm thinking of going to just a non-pumped thermo-siphoning system.

I almost made up a new cover plate for the pump location on the block, with a pipe nipple. But ran out of oxy-acet.

I notice that the piping on the pump system is 1" dia.

Is that what is found on the thermo-siphoning versions of these engines?

I thought I read 1-1/2" somewhere else.

I hope not, because I just bought 13 feet of 1" radiator/heater hose for the pump system. Also I'd have to make a new fitting for the head as well.