RB67 ProS maintenace & film back

I recently bought a RB67 ProS with 120 (ProS) & 220 (Pro) back, & lens of course. No apparent light leaks on the camera/120 back (left film in the camera testing for leaks) & shot a few rolls with the 120 back with great results, besides a few quirks -

The horizontal guides doesn't always retract when revolving to portrait, but finger taps to the base of the WLF will enable them to lower out of sight. Doesn't bother me too much.

On the 4th roll w/120 ProS back, when I advanced to the next frame the red dial started to not disengage, a first lightly wiggling on the winder would cause it to retract. If it didn't the ME lever could enable me to take the next shot. Later the winder wouldn't pop back after advancing to the next frame, but engaging the middle lever on the back popped it back into place.

When I loaded the 220 back, the film wound on fine, but after the first shot it would not advance.

So another back is its way. But would it be acceptable to keep using these & simply use the middle lever to advance to the next frame after each shot using the film counter as a guide?

With the red horizontal guides also not always retracting, is this related to the revolving back or signs of something else?

Are there certain repairs/cleaning jobs I could do myself to keep this beauty running strong? (I know periodic upkeep is advised) OR

if i wanted to send the body off to get tuned up, anyone have suggestions on where or who would do what's needed w/o costing an arm & a leg? (KEH prices seem pretty high for repairs)

The backs are just eisier to replace, not worried about repairing those - unless it's something I could do Let's keep in mind I shoot mostly for fun at this time, & the rest of the camera has performed well so far & is in decent shape But I do want to keep it going. Any advice would be welcome. Thanks!

Links that may help

Mamiya RB67 Pro-S Repair manual - Free PDF Download (81 Pages)

Mamiya RB67 Pro-S | Camera Service

Are you new to film cameras? Perhaps you bought a camera that is too complex to begin with

get the user manual here.....

Mamiya RB67 PRO-S instruction manual, user manual, free PDF manual, free manuals camera guide

check the back is an RB67 Pro S?

are you in multi frame mode or single frame mode?... under the film advance lever is a tab that is either on a red dot or not.

make sure the rotating back is fully clicked in place when you turn it?

where are you located?

Thank you, but I already have the manual & read through it multiple times before shooting. Consulting it during if needed. Then looked for any solutions online.

I am fairly familiar with this camera & have been shooting 35mm manual cameras for years. I've tried the difference suggestions listed in the manual problems & solutions section. They're both coupling to the revolving back fine. The ME wasn't flipped on, until the red dial on the frame counter would not retract after advancing. Then I flipped It on & off to allow me to shoot the next frame. It didn't feel like the film was spooled off kilter which could cause film advancing problens. After taking a shot the body engages that little rod which strikes the (top left) back to enable advancing to the next frame. Both backs advance fine despite the problem if using that lever used to wind up a partially unexposed roll if so inclined.

Just a little curious if anyone else had seen backs act like that. I'm in AR, US.

a cause for this advancing problem would be mismatched components, or the signal arm in the mechanics of the back needs alignment, and/or the wafer metering gear needs to be cleaned in the counter mechanism.

ok lets go over this again to be sure....

the film backs are pro s?

the revolving back is pro s? (2 silver tits where a pin pops out of when fired)

the body is pro s? has 2 tabs that align with the rev back pins?

take the rev back off n make sure the pins in those tits operate freely? wick in a micro dot of wd40 if sticking, that will free them.

a word of caution using rb backs.. dont let the advance lever snap back lioe shooting a 35mm camera. that will crack the advance lever mount stop made of cast aluminum.

if you are handy, pm me, i can tell you how to diy the film backs.

btw how did you make out with the enlarger?

Check - the Body & 120 back are both proS. (The 220 is a Pro, but I haven't used it since to the advance issue) I'll have to double check the revolving back, I'm 95% sure it is. I was planning on taking it off to clean behind it as well. I'll double check it's the right one. That's a good suggestion on the back, & sounds like the issue. When I get home later this afternoon I'll look it over & msg you about cleaning them.

Thank you Ron for the tips!

On the enlarger, I eventually found a really nice Aristo Cold Head & stabilizer for the Bes23. The VC one to boot! Used the mirror technique to get it aligned spot on. I am very pleased with the head! Esp getting back into MF printing. I'm in the process of figuring out a way to mount the VC filters above the negative, but not much room between the diffusion plate & carrier. I don't like the idea of the ones below the lens, but might just have to go that route if I can't rig something up. I've been on a Lith printing kick, so not an issue yet. As always you've been very helpful.