If anyone runs into this...
When I got my 4003 a few years ago, somehow, I backed off the mute off the thumbscrew too. Managed to get it back on without dis-assembly using a dental pick to position.
Yesterday, I finally got around to replacing the foam mute pad that I nicked up a little bit in the process.
So, for anyone that wants to know how to deal with this on the 4003 v2 bridge:
1. Measure the intonation positions of each of the 4 saddles and write it down. Note the centering of the rollers as they set the string-to-string spacing.
2. De-string the bass.
3. Unscrew the pickguard screws and find the ground wire that runs to the bridge assembly. You may need to unsolder it from the body of the pot it is grounded to if there's not enough slack wire. (I had to).
4. Unscrew the intonation screws (allen head) of each of the 4 saddles, careful not to lose the springs.
5. Set aside the 4 roller saddles in order. Note that the roller of each saddle is a unique size to fit the gauge of string. Keep them in order.
6. Remove the four phillips head screws under the saddles that hold the tailpiece to the body.
7. Lay a soft cloth on the bass and gently lift the tail piece up and flip it over. You may have to gently wiggle it to free it from the painted top and not damage the finish.
8. The mute bar/foam assembly is probably loose in the cavity under the tailpiece. There should be two springs for either side, and the grounding wire is soldered to the mute bar. Don't withdraw wire from the body all the way, leave the end of the wire in the control cavity so you don't have to chase it through later during assembly.
9. If you're replacing the foam pad, use a marker to mark the position of the existing foam pad and orientation of the bar (1st string and 4th string sides)
10. Remove the old foam pad by slowly peeling it up. A little heat from a hairdryer will soften the adhesive.
11. Clean the bar of remaining adhesive and check the shape with a 10" string radius gauge.
12. Carefully align the new pad (from Rickenbacker or their dealers), centering it on the metal bar using the alignment marks and the solder-rivet in the middle of the bar. Stick it down when you're sure it is in the center. Pinch the sides a little so it will go into the tailpiece a bit easier.
13. Put the plastic washers on the thumbscrews, insert them into the tailpiece from the topside, set the springs on them and thread them into the mute bar.
14. Check the operation of mute bar/foam and thumbscrews. Should move up and down smoothly and the pad shouldn't bind anywhere.
15. Carefully align the tailpiece with the marks on the paint where you took it off, pull the ground wire into the control cavity and put in the four retaining screws.
16. Re-solder the ground wire, carefully fold and dress the wires on the pickguard, install it back on the bass, make sure no wires are trapped or stuck, and put in the pickguard screws.
17. Put the intonation screws in, set the springs on them and put the roller saddles back in order.
18. Pre-set the saddles to the positions you measured when you took them out. I centered the rollers in the saddles at this point.
19. Install new strings and reset the intonation as needed. If you didn't disturb the saddle heights, they should be where you left them. The string rollers a little pesky and like to turn while you put on the new strings, so reset as needed.
Done.
Start to finish for me was only about an hour, including stringing and setting intonation. Saved a lot of time measuring the positions of the saddles before starting so was able to start with intonation pre-set almost perfect with new strings. Just a little tweeking to dial it in with the electronic tuner.
Seems like a lot of steps, but it was actually easy. Rics are weird, compared to Fenders, which are much simpler to take apart and service. Having the photos of how the bridge is assembled was super helpful. Exploring and figuring it out would take a lot of time otherwise.
The mute works well now.
My particular bass will go as low as just under 4/64's of an inch at the 12th fret string action with about .007" relief. At 5/64" action on the E and 4/64" on the G, it is rattle and buzz free and easy to play.
I installed an original Rickenbacker string set as well. They're a slightly weird set of gauges for a 45-105 set, and are clearly nickel-plated steel made by D'addario. The middle strings are a bit lighter gauge than most sets, the factory nut is filed specifically for them. They are pretty nice feeling though, seems to have a balanced tension. Also, the set seems to be a tad shorter than typical long-scale strings sets, which fit the 4003 slightly shorter scale well.
