mm251 stutters and pops

[tackit]

Could a mig gun cause a MM251 to weld, sputter and pop, weld, sputter and pop again? When it welds it welds good for a few inches. IT's stutters on starts too. The machine is like brand new, it's only had one 33 lb roll of solid wire through it. it's getting worse, I could deal with it before today, but today was the last draw.... it's almost 44 mag time.

[aametalmaster]

I would try a new liner. Remove the tip and loosen the wire from the drive rollers and see if it pulls thru freely. And also check the 5/8" nut on the center of the spool and make sure it isn't tight. Mine has to be run almost off...Bob

[tackit]

I would try a new liner. Remove the tip and loosen the wire from the drive rollers and see if it pulls thru freely. And also check the 5/8" nut on the center of the spool and make sure it isn't tight. Mine has to be run almost off...Bob

Thank you Bob, I'll go over the machine tomorrow. I'm going to buy a new Bernard gun for it if it's not the machine's electrics, the Q3015AE8XM model. Do you use Bernard guns? Do you like them?

[K.C. Brashear]

I agree with Bob. I would try a new liner, I highly recommend benard. They use "centerfire" tips I believe, they have no threads on them and work great

[tackit]

I agree with Bob. I would try a new liner, I highly recommend benard. They use "centerfire" tips I believe, they have no threads on them and work great

Thanks Brasher for your commenting...

I just checked Lincolns website, I must have a 44 lb spool of their ER70S-6 on the machine because I don't see a 33 lb fiber spool of it offered. That's a lot of weight, could be it's to heavy for the machine. Tomorrow I'll put on a 10 or 12 lb ? roll and see if that helps. I'll post back here tomorrow the results.

[Sberry]

Make sure the ground clamp is good. I wouldn't be buying a new gun till I figured out what was wrong.

[gnforge]

mm251 stutters and pops

I would also check the ground cable. They can act that way if ur loosing good ground. I personally don't like the OEM ground clamps, I replace them with a good brass one even on a new Michine. That Michine should handle a 44 lb. spool with no problem.
I would at least ck all ground connection nuts and grind area bare to connect ground cable.
Just a thought. Greg

[tackit]

Make sure the ground clamp is good. I wouldn't be buying a new gun till I figured out what was wrong.

I put a new Linco 300 amp copper ground clamp on it this spring, buying the new gun is OK, I'm getting the machine fixed if it needs fixing, fixing it is cheaper than buying a new one ..... I need to buy a new sandblaster too, my homemade one is supposedly a bomb.

[Texas113]

mm251 stutters and pops

I too like the Bernard guns for heavy use. Tackit I am interested in seeing some pictures of your "bomb" that you currently are blasting with. HaHa blasting and bomb used in the same sentence, wonder if that puts me on the "list". Seriously I would like to see how you built your sand blaster.

[tackit]

I too like the Bernard guns for heavy use. Tackit I am interested in seeing some pictures of your "bomb" that you currently are blasting with. HaHa blasting and bomb used in the same sentence, wonder if that puts me on the "list". Seriously I would like to see how you built your sand blaster.

Texas I can't figure out how to use Miller's picture posting software and I can't remember if I have the blaster pics on my photo bucket account, if not I'll have to find the pics and run them through photo bucket and then post the link here.

Happy to help a Texan.

[tackit]

Here's the blaster Texas, we better not use the word bo-mb, Obama's police will come and get us.





http://s1298.photobucket.com/user/cy...Sand%20Blaster

[weldonwelding]

isnt the machine still under warranty?

[tackit]

isnt the machine still under warranty?

No it's a 2003 model. I think it's the heavy fiber spool that's at the heart of my problems.... could be the hole in the fiber spool isn't perfectly round and it's square cornering a bit as turns too. I'll check everything out and change the liner tomorrow. Something isn't right, It welds good until the sputtering starts. Seems to sputter on starts a lot that's why I'm thinking the weight of the wire could have something to do with it .

[tackit]

I would also check the ground cable. They can act that way if ur loosing good ground. I personally don't like the OEM ground clamps, I replace them with a good brass one even on a new Michine. That Michine should handle a 44 lb. spool with no problem.
I would at least ck all ground connection nuts and grind area bare to connect ground cable.
Just a thought. Greg

Greg, I pretty much did what you're suggesting. thanks

[tackit]

Fixed stuttering and popping

If you have a 251 that stutters and pops on starts you can remove the # 8 or #79 wire (depending on your machine) from the contactor block and your problems will go away... at least mine did. My 2003 MM251 has never welded so nicely since I pulled the # 8 wire off the contactor. Thanks Miller for the Tip The #8 wire is the wire with the yellow marker on it.

http://s1298.photobucket.com/user/cy...y/MHS%20Remove