mig wire not feeding

[bobwills]

So we got got a miller 251 mig in the shop and here lately its been halving some problems feeding the wire. I changed it and it was feeding fine again. But it aint feeding again. The wire aint all that old but just wondering how long does wire usually last. But even without a tip in there it wont feed so im thinking need to change the lining out in it. What you all think.

[DVA]

So we got got a miller 251 mig in the shop and here lately its been halving some problems feeding the wire. I changed it and it was feeding fine again. But it aint feeding again. The wire aint all that old but just wondering how long does wire usually last. But even without a tip in there it wont feed so im thinking need to change the lining out in it. What you all think.

Are the rollers turning?

[todmorg]

Are the rolls slipping on the wire or are you getting a birds nest? Most Millers have reversible drive rolls for different wires.

[bobwills]

yeah i believe so. If i remember right it feeds in there a way but when it gets to a certain point then it stops and hardly moves. It might go all the way through but just hardly moves i dont remember.

[bobwills]

No its loose enough to just slip before nesting up. But its always been plenty tight to work before.

[todmorg]

Sounds like a bad liner

[jerky]

Bad liner or check your stinger, u said u took the tip out but did utake the gas diffuser out as well?

[parkour]

I agree with Jerky. On both of my wire feed guns, you have to remove the whole end of the gun to expose the end of the liner so the wire can feed out, then manually put the diffuser and contact tip back on.
It can work without taking the whole end off, but its easier to just take it off and be done.

[everlastsupport]

Remove the contact tip and diffuser, see if it feeds OK. If not, could be a dirt/bad liner. Wipe the wire with a white rag at the torch output. See if rust or anything. If it feeds, add the diffusers bad, try it, then a new contact tip or the old that is cleared.

That should get you to the area of the problem. Just had a Hobart I fixed with a bad liner. Does that unit see a lot of wire and does it sit in a dry area. The ER70 will get a light crust on it over time if humid and not used.

[jerky]

A good rule of thumb is every time u change your roll of wire, blow out the liner. But only use about 25-40 psi.

[todmorg]

On my Miller migs ( you were asking about a Miller, right? ) the liner goes right up to the contact tip, the gas diffuser goes over the outside of the liner with a small shoulder for locating and cannot hit the wire. The liner looks like an old fashioned choke cable, if the liner takes a bend or impact it will feed poorly.

Like others have mentioned, wipe your wire, blow clean with low pressure, and also make sure you don't have the wire crossed up on the spool.

Liners are also sized by wire size.

[DaveO]

Does that unit see a lot of wire and does it sit in a dry area. The ER70 will get a light crust on it over time if humid and not used.

Sounds like it might be a smart idea to remove the wire and store it in a dry place if the welder is not used for a while... or is this one of those "too obvious to state" statements.

[jerky]

Sounds like it might be a smart idea to remove the wire and store it in a dry place if the welder is not used for a while... or is this one of those "too obvious to state" statements.

sometime it is and sometimes it isnt. an easy way is just to cover your spool with a blanket or anything else.... but i know some companys actually have a special room for their wire, and once your done your weld, you take your spool off and put it back into the room. log it in and out. dirt and other contaminets can lead to a serious weld fault. hope you got your wire running again

[bobwills]

never thought to take the second part off. Will try that. And yeah we have been covering the wire in it with an old shirt because it dont get used too often anymore. It will sit for a good couple months sometimes between uses. They mainly bought it cause while back we got a few new coupany trucks and they used it to bould beds for on it to hold all the tools. And good idea blowing it out. That might help. It could of got bumped like you said and have a little bad spot in it too. Ive been told by a welder to just spray a little wd-40 on the wire every once in a while to keep it from rusting and also it will lube up the linner, only downfall is she smokes a little. Also to take a ear plug and put it on the wire right after spool to clean it some.

[bobwills]

So I need to change the liner in the mig at the shop and Ive been searching all over the web looking for this answer. Couldnt really find it so ill just ask you all. If I use .035 wire in the mig is it best to use the liner that is rated for .030 and .035 or use the liner for .035 and .045?