The gasket is important for the hydraulic lifter folks. The idea was to keep air from entering through the mating surface and contributing to aeration of the oil and air in the lifters. Same for using just a bit of thread lock on the pickup tube. Mechanical lifter motors, this is not so much of an issue. That being said, panic is quite right about using a gasket or not. Some pumps came with gaskets and some did not so the end clearances will be different between the two types of pumps. Thus, installing a gasket on a pump that did not have one originally might not be the best move. Conversely, not using one on a pump that did is also probably not the right move. And then there is the quandary of installing a thicker gasket where a thinner gasket had been previously installed.
With the cost of machine work and parts for these motors, it seems to me that maybe the better play would be to source a new pump and pickup rather then risk a potential failure of the motor down the road. I see NOS or RNOS pumps on ebay all the time for less then 100.
Last edited by Dragsix; 03/11/2020 5:54 PM.
