Question on Jabsco twist lock toilet pump

[Jim Hardesty]

I've read the instructions but don't really understand what the twist lock feature does except keep the handle down.  Before I call Jabsco thought I'd ask here. 
During this spring startup had a stripped screw and it leaked a little, replaced the original Jabsco toilet pump with a new twist lock pump.  Has been working a little glitchy compared to the original.  Takes more strokes to prime and just not the same.  Was happy enough with the original pump function, was a super easy change. 
Could this just be a break-in thing?  What does the twist lock thing do?
Just want to know before a minor thing becomes an o-s!@# thing.
Jim

[Noah]

The Jabsco Twist 'N' Lock Manual Marine Toilet's action safety handle locks the waste outlet valve shut, guarding against syphonic flooding and waste backflow

[Ron Hill]

Jim : Depending on where this stripped screw is on the old pump, you might just go all the way thru and use a nut and bolt!!

On the new Jabsco parts from China - I found that the replacement large "O" ring for the bottom of the pump does NOT slide easily unless the pump wall is coated with plumbers' grease!!  Have no idea what that "O" ring is made of, but it doesn't want to slide easily!! 

Stainless Screws into Plastic  -  When you replace the metal screws ALWAYS start them with your fingers.  Start them by turning backwards (counter clockwise) with your fingers to get it aligned into the old threads.  When you feel the screw drop into the threads then start to tighten the screw (clockwise).  If you immediately start the screw, the metal screw WILL make new threads (if not aligned) right over the old plastic threads!!  Then things are buggered up and the threads are stripped!!   

A few thoughts

[Jim Hardesty]

Stainless Screws into Plastic  -  When you replace the metal screws ALWAYS start them with your fingers.  Start them by turning backwards (counter clockwise) with your fingers to get it aligned into the old threads.  When you feel the screw drop into the threads then start to tighten the screw (clockwise).

Good advice Ron.  That's what I do.  Think this may have been a winterizing thing.  Did disassemble new pump and looked to be ample grease at the plunger.  Will try more grease if problem persists.
Jim