SA 200 welder spec question

I am just about ready to start welding with my refurbed SA 200. Notice I say refurbed, and not restored. There is something wrong with the sensor that kicks in the throttle when an arc is struck, and the regular idle/high idle switch seems inoperable. Neither work. I suspect a printed circuit board and the high/low switch. Solenoid seems to work, as does governor.

I have kicked up the rpms to the point where the governor starts to applying backpressure on the linkage, attached a temporary wire at that point, and welded with it. It welded with both 1/8 and 3/32 7018 rods just fine. The current jump switch and fine tune rheostat seem to work fine, too.

I removed the commentator cap, and the grooves between each contact on the commentator appear to be slightly less than 1/8" deep. I took a dentist pick and carefully cleaned each. The brushes are a full 3/4" thick, so have a lot of life in them. Either not used much, or changed and not a lot of hours on them. Springs and guides looked fine.

Hauling this to the Lincoln service center involves a 400 round trip, and if what I think is wrong with it is the problem, probably a $500 repair bill.

I talked to a Lincoln tekkie, and he said the high idle was 2300 rpm. I was wondering if I rigged up a throttle lever and just ran the throttle manually up to operational rpm range if that would be okay, and I could just leave the electronics dead where they are. Maybe just cut the wires. Does anyone know offhand what the operational load rpm of the motor is? Do you think that if I ran it at that rpm, then sparked an arc that the engine would die down enough rpms to make the welding current less?

I'm going to call the service center there tomorrow, and in the past they have been very helpful. However, I'd like to know if anyone here has some info they have gleaned from firsthand use, or perhaps have a manual for it. I downloaded the manual for the SA 200 from Lincoln, but it is thin in some areas as they used some different combinations of motors and generators. Info would be appreciated, and if someone has a SA 200 operator's manual that covers the Continental motor that would show all the inner parts and how to rebuild it, I'd be in the market.

It would sure be nice to have this running exactly like it's supposed to, but if I can make a $10 throttle linkage (or less) vs. a $500 bill to put it back entirely right, I'd have to weigh that. My main concern is that it will not hurt the engine or generator to run it with a manual control. It would be easy to make a lever with a spring release. I also want to disassemble the governor and clean and inspect and grease it to make sure it's functioning properly, hence I'd like to have a book.

The project is coming along. I got some red paint on it in various places and it looks cool. Now to get it working and make a few bucks to finish the aesthetic things like fenders and lights. And a 6" vise for the work bench. Maybe a new Smith propane torch head, too. A couple of good tires, and paint the rims.

Will post a couple of pix after I get home Tuesday of the progress.

Thanks, as always.

Steve

Reply to
SteveB
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If for some reason that doesn't work, maybe you could try an aftermarket cruise control, such as the ones made by Audivox. I've seen the vacuum actuated version for less than $100. Hmmm... connect a double throw switch to the "resume" and "brake" functions and tape it to the stinger? --Glenn Lyford

Reply to
glyford

Thanks, Gunner. I called the Lincoln repair shop here today, and the tekkie said I could run it on manual at 1550 rpm, which I was a little amazed at. He said the circuit board didn't go out much, and they could diagnose and fix whatever was wrong with it for around $300 tops. He said the circuit boards were under $100, so it sounds like they aren't marking up those a lot.

I'll get the old gal working, and some cash coming back in, and maybe I'll find someone locally up in Utah that can fix it, or may even figure it out myself. In the meantime, a manual setup on a tach will do the deal. I just didn't want to hurt it.

Steve

Reply to
SteveB

I was thinking my 73 model ran at 1750 rpm. But that was a long time ago, I could easily be mistaken. Does the online Lincoln documentation specify?

Reply to
Maxwell

If the linkage is correct and the governor is working it should maintain RPM pretty close to wherever you have set it, with or without load.

Don Young

Reply to
Don Young

That's pretty much the gist of what the Lincoln repairman told me. He said that the electronic controls were nice to have and to be working, but a lot of people were using manual throttles now that the repair costs for the old units was getting so high.

I have seen a lot of pictures of these units, and some look like mudpie targets at a county fair. Mine is pretty clean and nice looking. Some of the units I can see where spending three hundred bucks would be a questionable investment.

He did say that because of the low operational rpm, the Continental engines lasted a very long time.

Steve

Reply to
SteveB

IIRC your machine has a solenoid operated idler and not a vacuum type, I do not have a good record of your trouble shooting process or your results, IIRC you did report these in an earlier post but I could not find it easily. Please excuse me if I state the obvious or suggest you do something you have already done. All my suggestions are from memory and I have not consulted my manuals for data. I have had several similar machines over the past 30 years but have not needed to do much work on the governors or the idlers and all thoughts are IIRC.

With engine stopped

1 - I assume that you have inspected the governor and governor linkage and that it is free and not seized. 2 - The idler linkage and the iron pin in the solenoid should also be free and not seized. 3 - The carb linkage should be free to move through the complete range from idle to full throttle. 4 - Disconnect the solenoid leads, put a multi meter on the leads and check for continuity and also that there is no short to ground. If OK then apply 12V power to check the solenoid function. The solenoid should pull the iron pin into the solenoid and the carb linkage to the idle position against the idle adjusting screw.

With engine running but solenoid disconnected

5 - The governor should work properly and hold the engine at proper operating RPM under varying loads with the idler solenoid disconnected. If this is not happening then you need to fix the governor first.

The engine and governor is covered in the "Teledyne Continental Motors" "Industrial Products Division" "Operators Maintenance & Overhaul Manual" It should be available online but I do not have a URL link. Try very hard to find a copy of this manual, post a URL link if you find one online.

The proper engine operating RPM should be in the engine operating specs or in the idler control section in the Lincoln SA200 manual you said you found online. There should be a circuit diagram and a parts list for the electronic idle device circuit board and other information regarding the idler circuit and components should also be in this manual. Please post the URL link to this manual.

6 - If all is working properly so far then your problem must be in the board or just as likely in its wiring. IIRC, I have occasionally experienced failure of idler operation on very humid weather or after pressure washing, this has always cleared up after operating using the high idle switch and allowing the engine heat and air to warm and dry everything out. If the engine is cold and the weather damp then the engine seems to idle too slowly to have enough welder OCV to actuate the auto idler and cause the engine to speed up, when this happens there seems to be a very weak or no spark when striking the stick to the work, it can also mean a poor ground or electrical connection in the leads.

At this point I would remove the board for careful inspection and place in a warm dry place and allow to dry completely. I would carefully check all wiring and clean all connections. If you have a friend who understands electronics then you may be able to check the board components and it may be repairable.

Only after doing all the above would I consider purchasing a new idler board.

Good luck,

Reply to
Private

Already did most of the things you suggested. Talked to the Lincoln tech yesterday, and they said this machine could be run at 1550 rpm, and disregard the electronics. Will still look at the wiring, and look for simple things. Gunner provided a source for circuit boards at a reasonable price. I don't mind paying to get this fixed, as I like using equipment that is operating at normal parameters. Just want to get this ringing the cash register, then will spend dollars on the superficial nonessentials.

Just got back home today after some out of town work, so will putter with this as time permits.

Steve

Reply to
SteveB

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