I have an old flint & walling jet pump. It goes to a 120 gal. galv.tank w/ well mate bladder tank tee'd in. It does make a little sand and I blow it clean from a low tank valve about once a month.
The well is 220ft/ casing side (2" galv.)
105ft/ tubing side (1" PVC)
2 months ago I changed the leathers @ the foot. Afterwards
the switch cycling was operating fine and held good water pressure.
This week the pump began cycling more than usual.
I have the switch set @ cut in-35 psig.
cut off @ 60 psig.
This morning cut in, to cutoff, took 6 minutes.
From cut off to cut in took 14 min. That is a substantial leak.

I think I hear some cavitation happening also.
I understand from this forum patially clogged jets could cause cavitation.
Would they also cause a pressure drop?

Would leathers have a leak rate like this?
The jets are supplied by the casing side pressure.
Can the jet regulator cause cavitation if malfunctioning?
I'm about to pull the tubing again. If the jets are clear, I'll change the leathers and the foot valve again.

If I still have the problem I'm going to lean toward a leaky casing.
Do you think I'm looking @ a new well? If so
Do they make submersibles that fit in 2" casing? If not.
About what does a casing replacement cost?
Or what about will it cost for someone to punch me a new 3" hole and run new casing.
Ground is mostly sand and clay layers in Lake Charles La.

Sorry about the length and all the questions.
I just can't see down there.

And thanks to whoever is responsible for this forum.