I have dPXR drive on a 31 sun seeker that won't stay in neutral goes from forward forward Jams and neutral and then pops into reverse very dangerous and upsetting any ideas

It wont stay in neutral even if you hold the shifter at that position? On the linkage side they are pretty simple. If you remove the back cover of the drive, you will see a buttery with a metal rod attached to it. Remove the butterfly and check back side of it. This same butterfly holds the shift fork. There are 3 grooves/notches for F, N, and R. The notches receive a spring loaded ball to hold gear position. My guess would be your issue is wear on the notch/detent surface. Other possible is your linkage is out of adjustment, so actually shifting, relative to shifter position causing issues. Remove the shift rod from the butterfly, make sure butterfly is is in N detent. Check shifter/cable side to make sure it is in N position. Align cable/rod connection with barrel nut adjust.

Just saw your post #16 in other thread. Based on that post, it sounds like your shift interrupt switch is a likely culprit. They are very finicky to cable adjustment and routing, as well as they do occasionally go bad.

Thank-you for your response. I can get it into neutral with muscling and wiggling, but it is a struggle. the boat is in water so looking at drive is not possible. ​​​​​​​it's a 1994 DPXR so I see any shift interuptor part. I have just neutral saftey switches in control box. ​​​​​​​

The shift interrupts are a small red rectangular box rigged inline on the cable somewhere and work based on push/pull along the cable. I am not aware of any DPX R applications that did not include them, but what the heck do I know? LOL

Check along the shift cable run under the control box to see if you can find them.

Obvious question, but are your shift cables known to be good?

The other thing that just occurred to me with the shift interrupts is, the small wire connection to the switch was held on with a small magnet. They were not particularly hard to knock loose if your were working on something around them/inadvertently pulled on them

I changed the shift cables and there was no shift interruptor along the cables anywhere.