The only thing you need to do is keep it clean for sanitation purposes. The gearbox is packed with a special gear grease, and needs to be replaced only when repairs are needed. Repairs should be made only by Hobart technicians, as the work requires special tools and training. Please believe me, when I say there are no DIY jobs you can perform. Our kitchen has one like yours, and I won't go inside for any reason.
My apologies. After reading your last post, I took a look under the top cover of our model HL-600. It has a filler plug, but no sight glass. It's been serveral years since I've looked at one of these. I have to guess they've changed the design. I think there's still no need to add oil, unless there's a leak. I'll call my local Hobart servicer to see if I can find out what type of oil they're using. I'll post back, when I find out.
I'm not sure, but you can call(NNN) NNN-NNNNto find out. Ask for customer service. Our conversation has been lengthy, to be sure, but we've both learned things we needed to know. If my efforts have helped you, please click the accept button.
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