To avoid these ads, REGISTER NOW!

Millermatic 250x Problem

Crawl Awah

Well-known member
Joined
Nov 2, 2013
Messages
57
Location
DFW
I have a 1998 Millermatic 250x mig welder and it just stopped feeding wire. When the trigger is depressed it activates the gas and and you can hear the welder voltage engage. However, the wire won’t feed and the drive wheel doesn’t spin. I replaced the two relays but it didn’t help.

Any thoughts or tips?

Here is a link a to the manual. I’ve looked it over but I am no https://www.millerwelds.com/files/owners-manuals/o1319c_mil.pdf

I am building a roll cage for my Jeep and need this thing to work.
 
To avoid these ads, REGISTER NOW!

zkling

Well-known member
Joined
Jan 23, 2007
Messages
16,939
Are you getting voltage to the drive motor? Have you bench tested the motor? Do you have the roll pressure cranked way high?
 
OP
C

Crawl Awah

Well-known member
Joined
Nov 2, 2013
Messages
57
Location
DFW
Roll pressure is not the issue. The motor is out. How is the best way to test? It appears to be a 24vac motor.
 
Last edited:

zkling

Well-known member
Joined
Jan 23, 2007
Messages
16,939
Should be a dc gear motor, . 24v is about right, 2 car batteries in series would get you there. I'd start by checking for voltage at the motor when trigger is pulled.
 

matt_i

Well-known member
Joined
Mar 14, 2008
Messages
10,725
Location
SE Michigan
As Z recommended I would make sure that pulling the trigger gets voltage applied to the motor terminals (wiring inside the machine)

After that I would get the proper manual and a part number and start googling and see if you can pick it up locally if you are in a large enough area (see DFW so I bet there's a big Miller dealer somewhere that has it)
 

welder4956

Well-known member
Joined
Apr 8, 2010
Messages
3,067
Location
Birmingham, AL USA
As others have said, first check to see that you get ~24V to the drive motor leads when the trigger is pulled. If not, check the the circuit breaker CB1 for continuity to make sure it is not bad. If both are OK, it is a control board issue. Don't go out and buy a motor till you know for sure it is not the control board. Control board issue is usually the problem with these machines.
 
To avoid these ads, REGISTER NOW!

LXCam

ALLIANCE MEMBER
Joined
Apr 23, 2013
Messages
19,109
Location
AZ
Test to voltage at the motor or it looks to have a terminal block in there. Within the schematic the motor is ID’d as PM. The applied voltage to the motor should be dependent on the wire feed setting. Another words wide open throttle you should see 24vdc. And dialing back the speed a reduction in the voltage. And like someone else suggested you could wire a couple 12v batteries in series to test it.

Here’s a snap shot of the schematic.

4AE564A1-3335-4C3F-AF48-1595CE1C990F.jpg
 

Zebu Fellenz

Well-known member
Joined
Aug 3, 2010
Messages
1,687
Location
Phelps, NY
I can't help with troubleshooting but if you need parts I'll recommend millerserviceparts.com

I just finished rebuilding a Bobcat 250 to the tune of about $1,000 in parts and they consistently had the best pricing around and excellent customer service!
 

Downwindtracker 2

Well-known member
Joined
Jun 13, 2019
Messages
1,715
Location
BC
I have one, they are considered the second worst welder Miller ever made, the 250 was the worst.. The weldors complain of the arc, harsh, European like, but the real compliant is the high starting voltage, if you're not careful , it'll blow holes in sheet metal. Miller has a fix, I found it on Miller's forum or site. I didn't bother, I'm not much of an electrician. If you are in it, it might be worthwhile to do the modification. Each model after has been an improvement, they get rave reviews now.
 
OP
C

Crawl Awah

Well-known member
Joined
Nov 2, 2013
Messages
57
Location
DFW
I tested the motor and it worked and then I tested the voltage at the connections and was getting power that fluctuated with knob adjustments. I put it all back together and it worked. Thanks for the tips.
 
OP
C

Crawl Awah

Well-known member
Joined
Nov 2, 2013
Messages
57
Location
DFW
I have one, they are considered the second worst welder Miller ever made, the 250 was the worst.. The weldors complain of the arc, harsh, European like, but the real compliant is the high starting voltage, if you're not careful , it'll blow holes in sheet metal. Miller has a fix, I found it on Miller's forum or site. I didn't bother, I'm not much of an electrician. If you are in it, it might be worthwhile to do the modification. Each model after has been an improvement, they get rave reviews now.

I had a Lincoln 180 and it never welded very good. I got the Miller for free and sold the Lincoln. The miller is much easier to use if the wire keeps feeding. :shocking:
 
To avoid these ads, REGISTER NOW!
Top Bottom