<html><head></head><body><p dir="ltr">I've been doing a bit more research online. It looks like a hydraulic fluid with anti-wear additives will work, but I might need to go to a higher viscosity grade than would be strictly ideal for low-loss power transmission. I'll have to do a bunch of calculations to see how much of an efficiency hit that will be, but there are big advantages to using the same fluid for both.</p>
<p dir="ltr">Automotive motor oil would work for the gears, but is not optimized for hydraulic power transmission.</p>
<p dir="ltr">Sean<br>
</p>
<br><br><div class="gmail_quote">On March 25, 2016 6:29:35 AM MDT, hank pronk via Personal_Submersibles <personal_submersibles@psubs.org> wrote:<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12px"><div id="yui_3_16_0_ym18_1_1458908775440_2672"><span>Sean,</span></div><div id="yui_3_16_0_ym18_1_1458908775440_2672" dir="ltr"><span id="yui_3_16_0_ym18_1_1458908775440_2778">I use motor oil for hydraulic fluid all the time. I have a small 1\2 hp right angle gear box here that uses motor oil in it. I think it would depend on the load on the gear box.</span></div><div id="yui_3_16_0_ym18_1_1458908775440_2672" dir="ltr"><span>Hank</span></div> <div class="qtdSeparateBR"><br /><br /></div><div class="yahoo_quoted" style="display: block;"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 12px;"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;"> <div dir="ltr"><font size="2" face="Arial"> On
Thursday, March 24, 2016 11:15 PM, Sean T. Stevenson via Personal_Submersibles <personal_submersibles@psubs.org> wrote:<br /></font></div> <br /><br /> <div class="y_msg_container"><div id="yiv8168812609"><div dir="ltr">I want to know if there is such a thing as a fluid which is simultaneously suitable for hydraulic power transmission (piston pump / motor) and as a lubricant fill (circulated) in a custom bevel gearcase?</div>
<div dir="ltr">Sean<br />
</div>
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