So I take the thing apart, shitty velocity, figured sitting 10 years piston could use a cleaning and some lube.  Everything went great till a neighbor thought he'd help and I noticed the sear had fallen out and there was a spring on the ground.  Sure enough no tension on the trigger.  My dad and I have tried a variety of things over the course of hours to figure out how to get it back together with no luck.  Spent 2 days googling to see if I can find a cutaway of the gun, diagram, anything with no luck, so hope y'all can help. Worth noting that none of the pins in the unit will fit through the center of the spring. As far as the sear pieces go, if that's even what you'd call them the one piece slides inside the other.

So in this pic I can point out what I do know.  The pin in the lower left goes through the hole the line points at, and into that hole on the trigger.  The tiny hole in the back is where the pin holds the safety lever in, and in the top right that pic goes through the sear.  I'm thinking how I have the sear parts laid out is how it goes in the gun, but I don't see how that actually engages the trigger.



Now in this pic you can see where there a grooved area in the center of the trigger, possible resting surfaces and a oval hole.  Thought maybe the spring resides in there.  But it won't fit back in the housing.  



Different angle.



Housing



Same



Backside.



Sear thingy close up.



Any and all help would be appreciated and if people need more pics to attempt to help just let me know what you want to see and I'll try to get a pic.

I don't have that trigger but I could take some pics of the factory set up

If you wouldn't mind that'd be awesome.

BRB
ETA; after looking at both the one I have is nothing like that, it won't help, sorry
There's gotta be schematics out there

For10 years I've tried and haven't found anything, long time back I had velocity issues which made it group like shit.  Problem is it's made by Mendoza, but I can't even find info from them, but branded Benjamin, by crosman.  Paid more for it than my .22 rifles.  If I can figure out the sear, or firing mechanism I might just rig me up a different  spring for the trigger.  Should've got a Crosman 1377 and saved $125.

Thanks for having a look for me, I appreciate it.

Its only 5 8  pieces......you can do it !

First, you need to understand how all the parts work in relationship to each other without the springs.  Then you need to look at parts and determine which need spring pressure and in which direction.  

Also, as with many German inspired things, one part may do multiple tasks.  Though this gun is not made in Germany, it is a copy of some of their designs.  

Your first problem is to understand how the sear mechanism works.  It is different from most firearms.

I'd suggest doing the following:  Lay out the internal parts without springs in the cocked position.  Start with the piston and note how the sear engages with the tail.  Then position the trigger so that the top of its sear surface keeps the sear from moving downward.  Then look at the safety and determine if it just blocks the trigger, or the sear, or if it blocks both.

When the trigger is pulled, the sear drops down out of the way of the piston tail.  The spring tension on the tail is what applies the force to move the sear.  Note that the tail and sear are not straight but sloped slightly.  The sear will not hold the tail in place without the trigger blocking it from moving.

The bar that fits in the sear slot (with the slotted hole) usually does a couple of things.  The first, it is often the thing that engages the automatic safety when the gun is cocked.  The tail of the piston pushes this back which then moves the safety to safe.  The second thing that it does, and its primary purpose, is to hold the sear down after the gun is fired.  Upon cocking, as it is pushed back, it releases the sear to pop up and engage the tail.  At the same time the trigger pops under the sear locking it in place.  

Now, note what the various springs must do.  The one on the side of the receiver, holds that eccentric pin in two different positions.  I assume this is the actual safety and the lever rotates this out or in the way of either the trigger, sear or both.  The other end of that spring has to hook onto something which allows the proper movement of that pin.  Look for bluing wear, as this is a good indicator where things go.  It appears from the photo, that this spring may hook at the front.  Also, look in the stock for relief cut-outs as these can also give you a good idea where things might go.

The spring at the back of the safety lever pushes on that sliding bar in the sear.  This is what pushes it in the way after firing.  It is also the part that pushes the safety into engagement when you cock the gun.  

The torsion spring is the trigger return spring.  In your photos, it needs to be flipped over.  The little arm with the hook will engage on the pin on the trigger (the opposite side presented in your photos).  The longer arm will hook onto the pin in the top part of the receiver.  It will take some pushing to get the pivot pin back into place as you will be compressing that spring sideways.


Now without having this in hand, these are my best thoughts on how to assemble it.  There may be some things I've gotten wrong, however.  But, I think I've given you a better starting point than what you had.  

If you find things which still don't seem right, take a few more photos, especially with the internal parts laid out the way you think that they go.  That way we might steer you into how things really fit if they are somehow wrong.

I found an exploded view of a similar (it appears to share most of the parts) Mendoza rifle.  This may help.  It appears that there are supposed to be two trigger springs that are mirror images of each other.  You only have one shown in your photos.

The parts diagram is a bit small, but I think you can make it out.  

The parts diagram is here on a Google search:  Mendoza Parts Diagram

ArimoDave huge help, thank you so much.  Went over the floor with a magnet and can't locate a second spring, I'll try to put it together and see what happens with one spring.