Sorry if these questions sound stupid, but I don't want to damage the machine. Since I just bought this Hitachi EX270, I have no idea what kind of grease the former owner used for the turntable. Can anyone tell me what is the safest option to avoid any possible bad reaction between grease types? I know it should be a moly grease, but what else ???? I also have a question about how and where to grease the turntable. There is a grease zerk/fitting directly below the front of the cab, which must be one grease point for the turntable. A friend who ran another Hitachi for quite a few years said that about once a year they would remove an oval plate located in the battery box area and put about two tubes of moly grease into the cavity underneath. His memory seemed a little vague about this part of greasing the turntable. Does this make sense? Can anyone supply more details and instructions?
My JD120 has a oval shaped cover on the center front of the turn table, and is supposed to be full of grease to a depth of about 1 inch.
Well, not sure of the year of your 270, so you'd be best to consult a service manual, but if I remember right, hitachis often have a port in the tool box, you pull the cover off and can stick your hand in there to put handfulls of grease on the rotec gear. Not the funnest job in the world, but such is life. First scoop all the old grease out. Get someone you trust with your life to operate the machine and swing it at your command and you can grease it up pretty quick, just get your hand OUT of the hole before saying go to move another couple degrees. It has been a while since I last did one (knock on iron). As for the daily greasing, there is often two grease nipples for the rotec, one for the front and one for the rear. Both get 5 pumps at the start of the shift.
Ironflyer, you asked about the year. It's a 1995 EX 270 LC. So far I haven't been able to find manuals for the machine, so any advice is appreciated.
Take a look in the tool box or by the swing transmission and see if you can see that access plate. It should be large enough for your hand to pass through and held on by a couple of bolts. You'll need a 5 gal pail of grease, something that is EP rated and tacky would be a good bet, as it will resist washout and should have moly or other additives to help stand up.
I'm thinking you are talking about two different operations here. The turn table bearing, sometimes know as the Rotec or slewing bearing, usually has two or three grease fittings. There usually is two or three fittings together, one going directly into the bearing race and the other one or two being blocks that have tubes going to other parts of the bearing. Some machines have just one in front and one on the opposite side of the bearing. These usually get lubed weekly and only a couple of squirts in each fitting. Rotate the house a few times to distribute the grease. Too much grease and you force the rubber seal between the bearing halves out of place. The inside of the bearing is the outside ring of the swing gears. There is a tub sitting in the carbody and then the bearing is set on top. The tub is filled with grease and then the house is installed. The pinion gear is at the bottom of a reduction gear box which slows the speed of the hydraulic swing motor and multiplies the torq. The primary purpose of the grease is to exclude water from pitting the teeth out. It doesn't take much lubrication to keep the teeth from grabbing and grinding. The plate mentioned in previous posts is removed to periodically put more grease in as the old stuff sluffs down and away from the teeth over time. It really doesn't matter what kind of grease you use. I have used moly and lithium grease and never had a problem. What is not mentioned is there is another plate that is accessed from under the carbody. That tub is not fully sealed and water always ends up in there. Usually we would pull the bottom cover and tip the machine up to drain the water out of the tub. It is messy and a pain but really is necessary. After the water drains out, then reinstall the cover and put a couple of tubes in the house side. Swing the machine around each way a half a dozen turns and your are set. Good Luck