Weird orange powder

[Lander]

I have been restoring a new to me milling machine hbm profi 45. It is 10 years old but used by a hobbiest who had many hobby's so it wasn't used much. It is the same chinese model as optimum mb4 and grizzly g0761.

Now i wanted to replace the oil in the geared head so i drained it. I didn't open the head fully so i had no idea what the geares would look like but when i ran it everything sounded good. Now i removed the measure glas so i can peak inside and there js this orange layer on the gears. Do any of you know what this is?

I already sprayed a can of brake cleaner to get most of the grut out. But the orange layer stayed on. It isn't rust because i got a cottonswab and absored some degreaser. It came right of! Also it doens't cover the mating surfaces where the gears have been touching. The old oil wasn't also that bad.

What do you guys think? Open up the head or just poor the new oil in. I really didn't want to open up the head because it has already taken a long time because of my perfectionism. But if i must i wil.

 

[mcostello]

Could it be a layer of rust dust?

 

[Cadillac]

Looks like it condisated in the gearbox and rusted.

 

[Firstram]

Fill it with cheap ATF and run it for a while, the detergent should help clean it out.

 

[woodchucker]

I would want to know what it was. I would open it up. If you are really a perfectionist, you already were leaning that way.

 

[great white]

Looks like surface flash rusting to me.

Failing that, might be deposits from additives in the oil that was in it....

 

[Uglydog]

Sounds like condensate resulting in some rust.
Consider filling it with the specified lubricant, and running it for a while.
Then draining and refilling.
ATF might be a good cleaner for many things. However, if the detergents may also degrade some metals such as bronze.
I'd avoid anything but the spec lube as it is difficult to ensure it all gets drained.

Daryl
MN

 

[Lander]

Thanks for all the replies! I'm gonna try to get some cheap oil and flush out all the rust. I don't think i have enough gear oil to use it to flush out the rust and getting some new is quiet expensive because of the shipping cost( nearest machine shop is 1,5 hours drive). If it still bad after that i will open it but i'm afraid my skill level and the lack of tools isn't gonna make it an easy task.

 

[aliva]

You could also use diesel fuel for a flush

 

[Harry Knutz]

Thanks for all the replies! I'm gonna try to get some cheap oil and flush out all the rust. I don't think i have enough gear oil to use it to flush out the rust and getting some new is quiet expensive because of the shipping cost( nearest machine shop is 1,5 hours drive). If it still bad after that i will open it but i'm afraid my skill level and the lack of tools isn't gonna make it an easy task.

Do not use gear oil, Use what the mfg calls for, It should be ISO 68 Circulating oil, Which is a mineral oil with certain additives, But no detergents. As mentioned by another poster, Bronze and or brass can be degraded by certain oils. Mfrs call for specific oils for specific reasons.