Purging a current grease, for a new?

[clutchpain]

Hello to all.

I would like to know if there is a cartridge for the typical grease gun that is available (cheaply) to "Purge" the current grease in a fitting/component that is neutral to the "NEW" incoming grease one wishes to use, (compatibility) question?

I simply don't want to use $10.00 + grease cartridges to purge to a new grease type? Understand?

If not as above, then what cheap method is available?

Please do not suggest disassembly and cleaning of the object component, this would be stupid!

 

[Rand]

there is no neutral grease. you would need a cheap version of your preferred grease(same base type)
also simply overfilling wont really purge the majority out in certain applications.