Moen cartridge replacement gone wrong...

I did a "simple" cartridge replacement on my shower. The valve appears to be a Moentrol Valve, model 3570 (single handle). It's configured in a shower, with a diverter to a second faucet, a "rain" type one coming down from the ceiling.
I thought I was being clever when I turned the screw on the left and the water shut off - I have since found a drawing that labels it as the Stop-Check valve.
Once my new cartridge was in, the water won't come on. So I opened the stop-check valve screw and voila, the water comes on. Unfortunately, now it won't turn off unless I back the screw in again. I've botched this pretty good.
It may just be that I've messed up the cartridge replacement, but it's so straight forward I can't figure out what I could have done.
Any advice is greatly appreciated! - Mike

At this point, I'm wondering if maybe the valve itself needs to be replaced, and that it wasn't the cartridge. If that's the case, it's time to call a pro. But I'd appreciate any advice. Thanks - Mike

Are you talking about the balancing spool? Or the intricate stops. Balancing spool takes a big flat head screwdriver to remove. Can you post a picture?

It's not the big flathead slotted one, it's the smaller flathead slotted one (on the left). Yes, I will post a picture, give me a couple minutes... and thanks!

It's the one indicated by the red arrow.

It sounds to me as though one of the seals on the sides of the cartridge is either not there or is not placed properly.

Can I take the new cartridge back out, and then re-seat it, or once it's removed does it have to be replaced again?

Turn the water off using the two stops and remove the cartridge. With the cartridge out turn the stops back on slowly to flush out the valve. Sometimes parts of the cartridge remain in the valve.

johnjh2o said:

Turn the water off using the two stops and remove the cartridge. With the cartridge out turn the stops back on slowly to flush out the valve. Sometimes parts of the cartridge remain in the valve.

Click to expand...

My experience is more like OFTEN! Please follow johnjh2o's advice.

Thank you both, I will give that a try!

John and SHR, that worked like a charm! You guys are AWESOME! Thank you very much for your help. - Mike