I just got an 89 big20, and need some help. It runs perfect but will not hold a good arc with a 7018 1/8 unless it is set on the second highest range setting. It has been in storage for a while, and I was wondering if it could have a stuck brush or something like that.
it sounds like you need to replace you big blushes on the main part of the gernerator
You say "big brushes" I can only find 2 small brushes.
you have found the exiter brushes on the out end of the generator. open the door and there should be a cover around the main part of the generator.
This one has an alternator that runs off of the end of the armature. The only brushes I can find run on slip rings.
you mayhave to take it to a shop and have it load banked and they can tell you if something is wrong with the generator.... i talked to a friend of mine and he said that the windings might have went bad
I have 72 volts at the weld terminals but I just don't have the current. It welds good but you have to set it one click higher on the range and about 80 on the rheostat to burn a 1/8 7018. It has been sitting a while and I am wondering if it is worth the trouble to clean all the conections from the diodes.
that welder just may have to be used. when i went to building rigs last year i used a welder that had ben sitting off and on sense the 80s and the more i used it the better in welded
I did notice a bit of that yesterday. I ran it for 12 hrs on a job just to try it out.
By cammarp
Date 05-09-2007 00:23
Edited 05-10-2007 01:22
we have a pretty bad environment at work for welders, we blow our welders out about once a quarter to blow our the soot from plasma.... makes a WORLD of difference... if that doesnt do it we even slightly pressure wash them if they are really bad.
Thanks I will try that. Do you think it would be worth sanding all the conections anyway.
Robert, I have a Bobcat 225 that I haul on a trailer.On this machine there is a chassis ground that get's frayed and it will get weak. Also you might could replace the ground clamp.
Just my 2cents worth!
gawelder
Where are you at in GA. Gainesville here.
You may need to check the armature windings for over heating The older machines had a bad habit of burning out when the duty cycle was exceeded. One of the reasons miller machines have such a bad rap in the oil patch.