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GENERAL => CZ Gunsmithing => Topic started by: CZ75enthusiast on August 06, 2021, 12:17:49 PM

Title: CZ75D double action not working troubleshooting
Post by: CZ75enthusiast on August 06, 2021, 12:17:49 PM
Just received a used surplus  75D compact (eg European market P01) . The decocker lever is very stiff, and the pistol only functions in single action. It can be cocked, decocked with effort (eg the decock lever is stiff and needed several tries to function at first time.) 

The hammer falls when the trigger is pulled when cocked. I presume it would fire but I have not fired it given that it is not fully functional in DA only SA.

However, pulling the trigger with the hammer down does absolutely nothing. The hammer does not move to the rear and there is no resistance, as if the trigger is not connected to the hammer, eg that whatever linkage there should be between trigger and hammer is absent, broken or disconnected.


What steps should I take to troubleshoot? What parts are most likely missing or broken for this to be the case?
From reviewing previous Threads on this and other forums, I’m assuming it could be


1. Missing fixing insert plate (part 63 in manual)
2. Trigger bar lubrication
3. Broken or adjustment problem with trigger bar spring
4. Sear, disconnector or hammer spurs worn or broken

Anyone out there see this problem before and can walk me through what to check in what order? Have only field stripped so far not detail stripped.
Title: Re: CZ75D double action not working troubleshooting
Post by: Earl Keese on August 06, 2021, 01:26:16 PM
Is there a disco installed currently? Is the trigger bar spring riding in the grooves under the trigger bar?
Title: Re: CZ75D double action not working troubleshooting
Post by: Tok36 on August 06, 2021, 06:25:10 PM
   As Earl mentioned, the Trigger Bar Spring is the easiest place to start and may not require major disassembly to adjust, if it is intact. By removing the grips from the pistol you can get a good look at the TBS and check its status and adjustment.

   From what you describe it sounds like the Double Action is not resetting. Mechanically this means the the Trigger Bar is not popping up in front of the disconector. The Trigger Bar Spring applies up tension to the Trigger Bar so that the DA reset functions. Once the DA resets, this is how the Trigger moves the Hammer in DA.

Trigger>Trigger Bar>Disconector>Hammer.

When functioning normally, once the Hammer rocks back far enough in its DA travel, the Trigger bar slips off of the disco and the Hammer drops.
Title: Re: CZ75D double action not working troubleshooting
Post by: cntrydawwwg on August 06, 2021, 06:58:41 PM
Also, have you cleaned and re-lubed it? It’s a surplus, who knows what kind of gunk is in there?[emoji85][emoji86][emoji87]
     If you have cleaned and lubed, see the 2 answers above.
Title: Re: CZ75D double action not working troubleshooting
Post by: CZ75enthusiast on August 07, 2021, 10:22:40 AM
So... We took it apart and cleaned it. Very dirty. Still no go. The trigger bar spring is in place and appears to function. With the mainspring out, the trigger engages the hammer and it works in double Action, but when we replaced the mainspring it’s back to SA only. Thoughts?
Title: Re: CZ75D double action not working troubleshooting
Post by: CZ75enthusiast on August 07, 2021, 10:27:26 AM
Ok, it’s either the trigger bar return spring or wear on the trigger bar engagement point, because when I physically pull up on the trigger bar while pulling the trigger the hammer engages and moves to the rear.
Title: Re: CZ75D double action not working troubleshooting
Post by: CZ75enthusiast on August 07, 2021, 10:58:44 AM
Further to that, lifting up the trigger bar doesn’t fully engage the hammer, it goes back as far as half cock then slips. So it’s not (just?) the spring. So what parts should I be looking at to replace?  Trigger bar? Disco? Hammer?

Appears to work fine in SA. There’s a feeling of engagement when the trigger bar is manually lifted, and the hammer does start to move back but then slips. I’m assuming there’s a worn engagement point along the trigger bar > hammer chain, but what should I be looking for?
Title: Re: CZ75D double action not working troubleshooting
Post by: CZ75enthusiast on August 09, 2021, 12:19:13 PM
Is there a way to see if the disconnector is there without taking apart the whole sear/hammer assembly?
Title: Re: CZ75D double action not working troubleshooting
Post by: tdogg on August 09, 2021, 01:10:21 PM
So if the hammer cocks in DA without the main spring, there is a disconnector present.

The parts that control the length of hammer cocking during the DA stroke is the disconnector and triggerbar.  You should pull it apart and inspect the right "ear" of the disconnector, and the face of the triggerbar that the "ear" contacts.

The fact that you have stated the decocker lever is stiff is a red flag something else it going on.  I would detail strip the gun and inspect all parts for wear/damage.  Pictures of the action and parts would be helpful.

Cheers,
Toby
Title: Re: CZ75D double action not working troubleshooting
Post by: Jigo23 on August 09, 2021, 05:15:55 PM
I’d say punt and send it to Cajun Gun Works for some lovin’ :)
Title: Re: CZ75D double action not working troubleshooting
Post by: CZ75enthusiast on August 26, 2021, 04:30:19 PM
Sending it to Cajun means going through FFL. The last time I sent a gun off for repair via FFL the closest dealer to me charged me $75 for just handing my gun back to me. So, for now waiting on parts and when they are all in we’ll tear it down and see what’s going on. New trigger bar and new disco along with a spring and hammer set from Cajun should hopefully do the trick.
Title: Re: CZ75D double action not working troubleshooting
Post by: nicky on August 26, 2021, 09:56:49 PM
Speak with CGW. I believe that you can send and receive without going through a FFL. I have done it.
Title: Re: CZ75D double action not working troubleshooting
Post by: mkd on August 27, 2021, 08:43:50 AM
cz75, i would call CGW and speak to a gunsmith. Thomas comes to mind. they have been very helpful and i am betting they can tell you exactly where your problem is and how to fix it. their customer service is outstanding .