Jack hammer makita hm1304 lubricant used - Makita Hammering

You require Hammer Grease, All good tool shops should have grease to suit. see link below:-

Hammer Grease 90582 for Makita Power Tool eReplacement Parts

Beware that its an old type Makita where several parts are not are deliverable any more lubrication is the first reason leaking 2 seconds and if its leaking it becomes hot inside has lost its pneumatic working so the parts are become hot and will be worn soon and the person who works with leaking tools overload themselves rather than the work object.
Makita has sometimes problems in front of the impact bolts by its rotary hammers. to observate the part cilinder 331559-9 very carefull if its not torn nowhere and this applies also to part tool holder 323912-3 it must be smooth inside in front where the impact bolt is sealed
Makita HR3000C Parts Breakdown

A old black graphite or yellow grease lubrication of the brand Makita

183614-1 its the revision set for the HM1304 BUT be AWARE the B serie can have marketing technical differences its not selled in my country

There is no tension to adjust on the Makita HR4041C rotary hammer drill. If you are not getting the hammer action you think you should be it's possible the o-rings on the piston are damaged or not lubricated or the striker is stuck or not lubricated enough to work properly. If you're having problems with the bit turning, there are several gears that turn the bit that could be slipping or are stripped. If you need a manual or brakedown of the tool, one is available on www.makitatools.com. The insides of rotary hammers are fairly complicated so be carefull of what goes where if you decide to take the tool apart to check for internal problems.

Go to the Makita website at http://www.makitatools.com/en-us/Modules/Home/Default.aspx, put your model number in the search box at the top, click on the arrow and you will be presented with any models with similar numbers. Select your jack hammer and you will be able to download the manual and parts breakdown.

Go to http://www.makitatools.com/en-us/Modules/Home/Default.aspx, put your model number in search box in the top right. Two models of the HM1500 will come up, select yours and open the owner's manual. Find the paragraph labeled 'Lubrication' and follow it precicely. Demo hammers are very picky about what type of grease they use and how much. Too thick and they won't work, too thin and they won't lubricate properly and the parts inside are very expensive to replace. Same applies to how much to use.

Lack of hammering action usually indicates a lack of lubrication or worn piston orings. This hammer as well as many other makita hammers work with a piston moving forward and back within a cylinder. This piston moves a second piston within the cylinder with a pocket of air (pressure and vacuum). If there is a lack of lubrication or orings are worn, you will not get a good hammering action /force out of the second piston. Time for good cleaning and apply factory lube. Parts are at www.toolpartsdirect.com Good luck

Makita recommends using their brand of Makita Hammer Grease if you are doing the lubrication yourself.
You did not indicate a model number but all of their hammers have simliar instructions, 2 oz of grease, do not overfill which can cause faulty hammering or tool failure.

This is an older, discontinued model Makita that only works as a hammer drill. It does not have the dial selector the newer models have to switch from 'drill' to 'hammer drill' to just 'hammer'. If you need, there's a parts breakdown and user manual available at:

http://www.makitatools.com/en-us/Modules/Tools/ToolSupport.aspx?ID=352