Questions on a Hobart G-400

[Dave Vincent]

Hi All,
I have a new to me 1976 Hobart G-400 with the Chrysler 225 slant 6 engine. When I first got the machine I pulled all the covers off the welder generator removed the mouse nests by the generator brushes. Freed up the ones that were stuck and reseated any that did not look seated correctly. I also checked the exciter brushes and freed up 1 brush spring that was stuck. So all the generator and exciter brushes are free. I got it running and It welds and runs good. After getting it running I cleaned and packed the rear bearing per the book.
My first question is this when it is running there seems to be a lot of noise coming from that area. It is even worse with the cover on. I think that is due to it acting as an amplifier of the noise. Is this noise normal or is something wrong. 20 years ago I had a SA 200 and I don't remember it making any noise.
My second question is do you run these welders with the covers down or do you keep them up when running. I think my SA 200 book said to keep them down. But I am not sure about Hobart.
My 3rd question is what weight oil do you put in the governor.
Any thoughts or comments would be appreciated.
Thanks Dave

[lars66]

Is it brush whine you are hearing? maybe have to get an armature stone and clean up the armature. Far as running with the covers up or down the water temp. should be your guide altho if the carb wants to ice up after start up leave them down until it warms up. I would start with 30 weight oil in the govenor and see how fast it reacts.

[Dave Vincent]

lars66,
Thanks for responding. This machine has 4 sets of 3 brushes all the brushes closest to the center of the armature had one side of the brush eroded away (for lack of a better term). The brush holder that was making the most noise had a brush that more than half the width was eroded away. I found a place to get brushes and replaced the bad ones. It seems to be quieter now.
This machine does not have a water temp gage on it. I guess on a hot day I would have the sides up to let the heat out.
30 wt is the oil I put in the governor. I had also put that in the engine. It seems to work fine.
Thanks Dave

[Welder Dave]

Good application for a non contact thermometer.