After working for 2 hours I touched the hydraulic fittings on the boom and the fittings were hot to touch. I could keep my hand on them, but barely. Is it normal for the fluid to get that hot or is something wrong. Most of the fluid has been changed recently, and the return filter is new, though the new filter has a much smaller micron rating than the one it replaced. The excavator is an IHI 35N if that helps. Any help would be much appreciated.
Generally anything over 110 degrees F will feel hot to the touch. What you are feeling is most likely normal. I use an infrared thermometer to check that kind of stuff. You can get them for less than a hundred bucks now. Good Luck
The way you descibe"hot to the touch, hold your hand on it barely" should put the temp around 140 F. The oil you are using makes a difference as 140 F with an ISO 32 oil will be more detrimental than say 140 F for an ISO 68 oil. Old school of thought was that oil started to breakdown and the life of the oil shortened significantly above about 150 F. There has been a lot of improvement with VI (viscosity improvers/additives which reduce the amount of viscosity change in relation to temp) in the recent past. I would verify what the temp actually was and see what my pump manufacturer recommended(probably 87-200SSU or so) and look how this related to the oil I was using. Hopefully you will be in the normal range. Good luck, Maytag
Not real familar with the 35N components myself, but most excavators use an oil cooler at the radiator. Have you made certain it's not clogged with dirt/debris? I agree with John C, need an infrared temp gun to get a better idea of what's going on.
It's normal yes for oil to get warm/hot with use.
what was your ambient air temp? If its 95 in cali, of course your hydraulic oil will be warmer...