Re: E70B hydraulic tank drain

There is nothing inside of the tank to prevent the oil from coming out of the drain during the installation of the drain line.  The recommendation is to pull a vacuum on the tank before installing the drain line to be safe.  Another option is to drain it with a diaphragm pump from the top, get most of it out, and then pull the bottom plug - which will help get debris out the bottom hole.  For further questions, please contact your local Cat dealer:


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E70B hydraulic tank drain

The service manual says to remove the 1-1/4" plug and insert a pipe nipple to open the drain valve. Is there a valve inside the tank that opens when the pipe is screwed in? Or will I get an oil bath when I remove the plug?