1950 SA-200 short hood welder

We got the welder started today for the first time. It runs and
generates current.
We got it started with a mystery Carter carburetor I bought on ebay.
It is an updraft type carburetor and the flange fits the engine
manifold. However, the linkage does not allow for hooking up either
the rod on the governor at the back of the magneto or for the rod that
goes to the vacuum diaphragm device.
Furthermore, we were not able to get any significant speed out of the
engine.
Nevertheless, it has decent oil pressure (about 25 at a hesitant rough
idle and doesn't smoke significantly.
Do any of y'all have an understanding of how the vacuum diaphragm, the
carburetor, and the governor interact with each other?
The vacuum diaphragm has a doodad on the bottom that looks sort of like
an ignition points capacitor. It is mounted behind the diaphragm and
has a broken wire. My son thought it was a mercury switch. But I
don't have a clue.
In any event it's broken. And I'm told that Lincoln obsoleted the
entire system long long ago.
Therefore, one of my first decisions will be what to do about the
carburetor and the idle system.
But I really don't even know what it does. Am I correct that these
systems automatically increase/decrease the engine speed as needed?
I'm still a long way from welding with it.
Thanks for any and all advice.
Vernon
Reply to
Vernon
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Try consulting a Massey Fergusson Dealer, as they used the same engines in the MF 35, and MF 77 model tractors. (this information found on another discussion board).
Reply to
Thomas Kendrick
Some of the machines use a low idle system. The idea was that when you were not welding the engine would be at idle. When you struck up welding current would activate a solenoid and pull the throttle open via the governor. When you stopped welding the current stopped flowing and the solenoid would release allowing the engine to idle. I am guessing your old system used engine vacuum to pull the throttle. In any case you can run the engine at governed speed and just weld. When you stop welding the engine governor will maintain high idle. When run in this manner the welding machine will burn a lot more fuel. The problem with speed must be a carburettor problem. My guess your idle circuits are working but your main jets are clogged or there is some other form of fuel starvation. You might try choking the engine to see if the speed instantly increases of decreases before it dies. If the engine runs better with choke on or slightly speeds up then you have a fuel starvation problem. Just a side note: Down draft carburettors tend to promote fires in a variety of situations. If the engine intake is flooded fuel vapour and gas descends out of the carburettor especially if the air filter is removed. In a downdraft situation the dangerous fluids and vapours fall into the engine intake. Keep this in mind when fooling around with air filter off. Randy
We got the welder started today for the first time. It runs and generates current.
We got it started with a mystery Carter carburetor I bought on ebay. It is an updraft type carburetor and the flange fits the engine manifold. However, the linkage does not allow for hooking up either the rod on the governor at the back of the magneto or for the rod that goes to the vacuum diaphragm device.
Furthermore, we were not able to get any significant speed out of the engine.
Nevertheless, it has decent oil pressure (about 25 at a hesitant rough idle and doesn't smoke significantly.
Do any of y'all have an understanding of how the vacuum diaphragm, the carburetor, and the governor interact with each other?
The vacuum diaphragm has a doodad on the bottom that looks sort of like an ignition points capacitor. It is mounted behind the diaphragm and has a broken wire. My son thought it was a mercury switch. But I don't have a clue.
In any event it's broken. And I'm told that Lincoln obsoleted the entire system long long ago.
Therefore, one of my first decisions will be what to do about the carburetor and the idle system.
But I really don't even know what it does. Am I correct that these systems automatically increase/decrease the engine speed as needed?
I'm still a long way from welding with it.
Thanks for any and all advice.
Vernon
Reply to
R. Zimmerman
Randy,
Thank you very much for your usual spot-on-point comments.
My son was tinkering with the carburetor side today. And I continued to be quite worried about a flashback fire. So your comments put that issue squarely to the top of my priorities. i.e. safety.
I have a Donaldson air filter that came off an Allis Chalmers forklift that has a Continental F163. I'm moderately sure it will work on the welder.
But tell me this. When you strike an arc, whether at 20 amps or 200, does the engine kick up to its governed speed limit of 1400rpm and then fall back to idle or high idle when you break the arc?
As to the carburetor it is a Carter. However, a local welding guy was stunned to learn that I had a Carter that would fit the welder. I bought it on ebay. But I don't remember anything about it. I also bought a Zenith that was SUPPOSED to be the upgrade model for the SA-200 welder. And indeed, although the linkage looks quite similar to the original Marvel Schebler carb, the mount stud spacing is bigger and the carb won't mount on the intake.
I remember that disappointment right after I bought this welder about 5 years ago. However, at some point I bought the Carter carburetor. But I can't remember a thing about it. In any case it appears to be a brand new "old stock" carburetor. My son Mark, who has inherited his mother's mechanical genius, has come to the same conclusion that you do. I.e. that the engine is being starved for fuel. Tomorrow I'm gonna let him call the shots. Every time I roll over and let him or Queen Bee do things THEIR way, fur flies and shit happens.
If he can get the carb to feed the engine to 1400rpm and it runs good and stays cool I'm off to weld up some fence.
By the way, can you tell me what that pin does when placed into the vacuum idle system? It would appear to keep the diaphragm from expanding or contracting.
Is that the high idle you're talking about?
V R. Zimmerman wrote:
Reply to
Vernon
With the portable machines I ran often you would scratch a false start to get the old girl to rev up before starting your weld. Better machines responded fast enough that you could just start welding and the engine would pickup the load. When you broke the arc the unit would drop back to low idle. At low idle the vacuum would high so the vacuum would act on the diaphragm which would pull the throttle closed down to low idle. When the arc is struck somehow the vacuum on the diaphragm is released or discontinued. A spring pulls the linkage back the other way and opens the throttle to allow the engine to run at high speed. This is just off the wall. I haven't seen your particular system. That "pin" you mention likely cuts off or opens the vacuum to the diaphragm. If you can't get the control system to work then just leave it on high idle. Those old flat head Continentals are amazing. In modern times we make things so complicated and sophisticated. The end result is that things die. Those engines are almost indestructible. The updraft carburettor is difficult to flood but.... great for starting fires. Just a word to your offspring. Tell him you want to keep the genetic line. :'))
Randy
Randy,
Thank you very much for your usual spot-on-point comments.
My son was tinkering with the carburetor side today. And I continued to be quite worried about a flashback fire. So your comments put that issue squarely to the top of my priorities. i.e. safety.
I have a Donaldson air filter that came off an Allis Chalmers forklift that has a Continental F163. I'm moderately sure it will work on the welder.
But tell me this. When you strike an arc, whether at 20 amps or 200, does the engine kick up to its governed speed limit of 1400rpm and then fall back to idle or high idle when you break the arc?
As to the carburetor it is a Carter. However, a local welding guy was stunned to learn that I had a Carter that would fit the welder. I bought it on ebay. But I don't remember anything about it. I also bought a Zenith that was SUPPOSED to be the upgrade model for the SA-200 welder. And indeed, although the linkage looks quite similar to the original Marvel Schebler carb, the mount stud spacing is bigger and the carb won't mount on the intake.
I remember that disappointment right after I bought this welder about 5 years ago. However, at some point I bought the Carter carburetor. But I can't remember a thing about it. In any case it appears to be a brand new "old stock" carburetor. My son Mark, who has inherited his mother's mechanical genius, has come to the same conclusion that you do. I.e. that the engine is being starved for fuel. Tomorrow I'm gonna let him call the shots. Every time I roll over and let him or Queen Bee do things THEIR way, fur flies and shit happens.
If he can get the carb to feed the engine to 1400rpm and it runs good and stays cool I'm off to weld up some fence.
By the way, can you tell me what that pin does when placed into the vacuum idle system? It would appear to keep the diaphragm from expanding or contracting.
Is that the high idle you're talking about?
V R. Zimmerman wrote:
Reply to
R. Zimmerman
Vernon,
I have a 1947 SA200 which is probably quite similar to yours. Those are fine machines so don't give up on it. What you really need is the original Marvel carb - they are available at Foley's
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as are most of the other parts you may need for that F162 engine. The other day I saw a site (can't remember where - I think I probably Googled "Lincoln SA200") that encouraged the use of those old pipeline welders and sold a couple of upgrades - one was an electronic version of the vacuum "rev-up" device that our old welders have. The other two upgrade parts were an electronic ignition to replace the magneto, and an air filter system that was represented to be superior to the oil bath system that came with your machine. There really isn't any reason to replace the magneto - parts are available and they usually don't break. The rev-up device is another matter because parts are hard to come by although they are fairly durable. Unfortunately the electronic rev-up was about $400 but represented to be the permanent end of all problems and much more responsive and precise than the vacuum system.
Another great resource for information and parts (albeit expensive for parts) is Lincoln itself. I bought my machine from the original owner in 1996 and because it was so complete (even still had the decals and the side panels) I wanted to restore it. I called Lincoln and spoke to someone in their tech department who had been there 30 years or more - he was quite friendly and interested in the old machine and very helpful - to Lincoln the code and serial numbers are everything; the code more than the S/N - I called back yesterday to learn that the fellow that I had talked to 12 years ago had retired two weeks ago, but the lady (Jamie Borkowski, if you want to call her) that helped me was just as helpful. A great resource; also, Lincoln is quite interested in those old machines and even the old style "Shield Arc" decals and the face plate are available from another site (linked to the Lincoln site).
Does your machine have a starter or is it a hand crank? Mine never had a starter or ring gear - the regulars on this forum know of my somewhat eccentric attempts to get around that problem including motorizing the generator to start the engine (quite do-able), etc. It's not hard to start if the carb is set up right - another benefit of the magneto.
If you haven't been able to strike a strong arc, or get the machine to rev-up to the 1400 rpm, you may have an exciter problem. Mine developed such a problem; the symptoms are that when you attempt to strike an arc, even if you short the stick, the engine won't rev up - I was less knowledgeable then and simply took it to the Lincoln dealer who fixed it. I messed around with the rev-up device but that wasn't the problem at all. It had something to do with the exciter, but I don't remember what - someone on this forum will know exactly.
One other thing that is important if you don't use the machine a lot - put good filtering on the fuel line. Those systems tend to "gunk up" with either rust or just shellac and other fuel crud. Mine is kept outdoors in West Texas which is pretty dry so rust inside the tank isn't much of a problem, but crud left by evaporating fuel is. There are two holes in the bottom of the gas tank - one feeds the carb and the other is just a drain, I suppose. Anyway, I put a valve on the second hole and just drain the fuel when I'm not going to use the machine for awhile and that pretty much ended the crud problems. Stabil is a good fuel stabilizer for long term storage, but I don't think it helps on the evaporation problem.
Good luck with that old machine - for stick welding it's about as good as they get.
Bruce
Reply to
bfrlaw
Bruce,
Good to hear from you!
Up to now we're running the thing with an old Carter updraft carburetor. It fits the machine but the linkage will not accept the rod from the vacuum bellows or the rod from the governer.
Therefore, I don't know what's working. Thanks to Randy's admonition about the flash fire hazard of the updraft carburetor design my son is over fishing for the Donaldson air filter I took off an Allis Chalmers forklift that has an F163 engine.
If that air cleaner won't work I'll buy one from weldmart. That might be the place you were looking at for the idle upgrade kit.
Where are you in Texas?
We live in Brenham.
Vern> Vernon,
Reply to
Vernon
Vernon,
Weldmart is where I was talking about. I'm in Austin, but my welder is on a ranch near Junction.
Bruce
Reply to
bfrlaw
Hey Bruce,
We used to hunt deer on a ranch northwest of Harper.
V
snipped-for-privacy@sbcglobal.net wrote:
Reply to
Vernon
Bruce,
This welder has a hand crank plus a 6 volt charging system and push button start. I borrowed a new 8 volt battery from my Farmall Cub tractor to start it with. The charging system on the tractor wasn't working so the battery was a little flat. After briefly charging it with a 12 v charger on the 2 amp setting (5 minutes at a time) I abandoned it and set up a 12 v battery. I disconnected the generator from the circuit.
Twelve volts spins it like an egg beater.
V snipped-for-privacy@sbcglobal.net wrote:
Reply to
Vernon
The little pin on the end of the little chain, when put thru the little hole in the linkage pins the engine at high idle. You really need to get a set of manuals, and the proper carb.
JTMcC.
Reply to
JTMcC
Don't know if its relevant, but you should check out
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have an aftermarket replacement for the idler control board for the SA200.
Reply to
Potblak
Thanks, Potblak.
Your link was quite interesting.
V Potblak wrote:
Reply to
Vernon

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