S&T Vss vintorez AEG Not firing

The anti reversal latch is the bit I've highlighted in pink.

It should follow the direction in blue, and catch the other side of the bevel gear. The bevel gear has a pattern cut in it so the anti reversal latch will only allow the gearbox to rotate in one direction.You also have it in upside down I think, the flat side should be on the face of the bevel gear, The curved part should be down under that gear. They require 3 hands to fit.

27287833847_7bc8fc2643_b.jpg



For grease you can use pretty much anything that lubricates and doesn't fly all over the place. There are numerous cheap options but I tend to stick with some cheap Ebay greases that come in handy little pots.

I use this stuff on pistons/air nozzles.

https://www.ebay.co.uk/itm/SYNTHETIC-SILICONE-GREASE-TEFLON-50g-TIN-2HT-PLASTIC-SAFE-LOW-FRICTION-/391399159157?hash=item5b21353575

and this stuff on gears.

https://www.ebay.co.uk/itm/Molly-MOS1-Grease-Airgun-Servicing-50-GRAM-TIN-/173321340281?hash=item285ac1c579

It's nice and cheap, and works really well for airsoft gearboxes. You don't need a lot for it to work just a small dab or two enough to get into the gears and protect them.

 
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Standard ones generally don't have an o-ring, Upgraded ones might.

You can measure the nozzle and pick one that is the same length if you can't find VSS specific ones if you think the nozzle is at fault. AK2M4 have a selection of cheap upgrade nozzles and provided you can get the correct length and it fits the hop there will be no other problems.

https://www.ak2m4.co.uk/internal-parts/air-nozzles

Looking at that picture:

The anti reversal latch isn't in correctly and it's very light on gear grease. (chances are you have already corrected this).

The slides for the piston could do with some grease as well. And that shell has a slight casting deformity so it's not straight. Just run the piston on it and make sure the piston runs without any binding.

The inner barrel is also 430mm so you might want to see if you can grab a non ported cylinder to see if it improves the guns consistency.

The trigger dolly could do with a very light smear of grease on the plastic ways. And check the gap of the contacts if it looks too wide just give them a little poke to close the gap a little (not enough to pinch the bridging contact tho).

Did you remember to put the spring in the cut off lever when you tested it?

Evike have a VSS gearbox with the selector in place, It might be a decent image reference for the selector rebuild.

https://www.evike.com/products/61951/


The anti reversal latch is the bit I've highlighted in pink.

It should follow the direction in blue, and catch the other side of the bevel gear. The bevel gear has a pattern cut in it so the anti reversal latch will only allow the gearbox to rotate in one direction.You also have it in upside down I think, the flat side should be on the face of the bevel gear, The curved part should be down under that gear. They require 3 hands to fit.




For grease you can use pretty much anything that lubricates and doesn't fly all over the place. There are numerous cheap options but I tend to stick with some cheap Ebay greases that come in handy little pots.

I use this stuff on pistons/air nozzles.

https://www.ebay.co.uk/itm/SYNTHETIC-SILICONE-GREASE-TEFLON-50g-TIN-2HT-PLASTIC-SAFE-LOW-FRICTION-/391399159157?hash=item5b21353575

and this stuff on gears.

https://www.ebay.co.uk/itm/Molly-MOS1-Grease-Airgun-Servicing-50-GRAM-TIN-/173321340281?hash=item285ac1c579

It's nice and cheap, and works really well for airsoft gearboxes. You don't need a lot for it to work just a small dab or two enough to get into the gears and protect them.
Hello, 

Thanks for the info and the vss gearbox image helps as its the exact one.

Will get some of that grease.

Not sure what you mean in spring in cut off lever? 

I'll do that with the latch, is the bevel gear above the flat one?

 
The anti reversal latch is the bit I've highlighted in pink.

It should follow the direction in blue, and catch the other side of the bevel gear. The bevel gear has a pattern cut in it so the anti reversal latch will only allow the gearbox to rotate in one direction.You also have it in upside down I think, the flat side should be on the face of the bevel gear, The curved part should be down under that gear. They require 3 hands to fit.




For grease you can use pretty much anything that lubricates and doesn't fly all over the place. There are numerous cheap options but I tend to stick with some cheap Ebay greases that come in handy little pots.

I use this stuff on pistons/air nozzles.

https://www.ebay.co.uk/itm/SYNTHETIC-SILICONE-GREASE-TEFLON-50g-TIN-2HT-PLASTIC-SAFE-LOW-FRICTION-/391399159157?hash=item5b21353575

and this stuff on gears.

https://www.ebay.co.uk/itm/Molly-MOS1-Grease-Airgun-Servicing-50-GRAM-TIN-/173321340281?hash=item285ac1c579

It's nice and cheap, and works really well for airsoft gearboxes. You don't need a lot for it to work just a small dab or two enough to get into the gears and protect them.
Well just checked the gear while trying to address the reversal latch issues and a tooth has broken off a gear. Other gears won't seem to turn all together fully either.

View attachment 34686

View attachment 34687

 
You'll need a new gearset then.

The standard ratio is 18:1 and V3 boxes need the standard gears.

https://www.ak2m4.co.uk/internal-parts/gears/zci-gear-set-18-1

or these

https://www.ak2m4.co.uk/internal-parts/gears/shs-ra-standard-gear-set

I'd probably go with the standard £10 gearset to keep costs down.

The anti reversal latch goes in looking like this.

Hopefully you can see with the image.

41275942285_7d9b110701_b.jpg



The flat side is onto the bevel gear, and the spring holds it to the gear all the time.


Chances are when you ran it with the AR latch in the wrong position it caught the tooth on the spur gear and removed that tooth. You have to have a good look for the missing tooth to make sure it's not hiding in the gearbox ready to break something else in the future.


The gears not turning well could be that old grease, or that missing tooth. You have to fully strip it to inspect. And it would be a good idea to remove as much of that grease as possible and drop some light oil into the bearings to free them up. It doesn't need to be fancy oil 3 in 1 will do (you can also use it to clean the grease off) then re grease with the ebay stuff when that arrives.

You need to remove the main spring, piston and tappet plate to see the gears moving. All of those components will add resistance or stop the gears.


The spring I mentioned for the selector plate/cut off lever is located on the back side of  the gearbox.

41455571844_392c485ab7_b.jpg

 

 
You'll need a new gearset then.

The standard ratio is 18:1 and V3 boxes need the standard gears.

https://www.ak2m4.co.uk/internal-parts/gears/zci-gear-set-18-1

or these

https://www.ak2m4.co.uk/internal-parts/gears/shs-ra-standard-gear-set

I'd probably go with the standard £10 gearset to keep costs down.

The anti reversal latch goes in looking like this.

Hopefully you can see with the image.




The flat side is onto the bevel gear, and the spring holds it to the gear all the time.


Chances are when you ran it with the AR latch in the wrong position it caught the tooth on the spur gear and removed that tooth. You have to have a good look for the missing tooth to make sure it's not hiding in the gearbox ready to break something else in the future.


The gears not turning well could be that old grease, or that missing tooth. You have to fully strip it to inspect. And it would be a good idea to remove as much of that grease as possible and drop some light oil into the bearings to free them up. It doesn't need to be fancy oil 3 in 1 will do (you can also use it to clean the grease off) then re grease with the ebay stuff when that arrives.

You need to remove the main spring, piston and tappet plate to see the gears moving. All of those components will add resistance or stop the gears.


The spring I mentioned for the selector plate/cut off lever is located on the back side of  the gearbox.


 
Damn new gearset, I found the little piece before noticing the gear and removed it. 

Ah I see, yes that spring on the back is in there.

After correcting the latch, and fixing selector plate the gun now fires okay, although getting it on auto was a pain.

Going to leave it alone now until I get the parts, thanks for the help. I'll update when I can.

 
Update, added new gearset, regreased gearbox and gears, added new piston head. Air comes out great.

Having an issue with trigger/selector semi sometimes skips, not a full cycle. Response is crap, misfires also.

Gearbox in general sounds very clunky still.

Please check video. https://youtu.be/qLpxqxWe8jA

 
You'll need a new gearset then.

The standard ratio is 18:1 and V3 boxes need the standard gears.

https://www.ak2m4.co.uk/internal-parts/gears/zci-gear-set-18-1

or these

https://www.ak2m4.co.uk/internal-parts/gears/shs-ra-standard-gear-set

I'd probably go with the standard £10 gearset to keep costs down.

The anti reversal latch goes in looking like this.

Hopefully you can see with the image.




The flat side is onto the bevel gear, and the spring holds it to the gear all the time.


Chances are when you ran it with the AR latch in the wrong position it caught the tooth on the spur gear and removed that tooth. You have to have a good look for the missing tooth to make sure it's not hiding in the gearbox ready to break something else in the future.


The gears not turning well could be that old grease, or that missing tooth. You have to fully strip it to inspect. And it would be a good idea to remove as much of that grease as possible and drop some light oil into the bearings to free them up. It doesn't need to be fancy oil 3 in 1 will do (you can also use it to clean the grease off) then re grease with the ebay stuff when that arrives.

You need to remove the main spring, piston and tappet plate to see the gears moving. All of those components will add resistance or stop the gears.


The spring I mentioned for the selector plate/cut off lever is located on the back side of  the gearbox.


 

 
I watched the video,

The scratchiness is because of your motor height. There is a grub screw at the bottom of the motor, Screwing it in and out will change how the gearbox meshes and make it sound better or worse. You've changed the gears so the Motor height will need adjusting to match the new gears. 

The selector plate is in correctly.

The misfires are the trigger dolly. It's getting caught in the fall back stage. So have a look at the spring and see if you have anything blocking the dolly. The cut off is resetting, the dolly isn't getting caught in the contacts. So it has to be with the dolly falling back and resetting. Perhaps the spring is weak, or the ways have a burr or tight spot. I'd be tempted to give it a blast of silicone spray to see if it solves it.


 

 
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I watched the video,

The scratchiness is because of your motor height. There is a grub screw at the bottom of the motor, Screwing it in and out will change how the gearbox meshes and make it sound better or worse. You've changed the gears so the Motor height will need adjusting to match the new gears. 

The selector plate is in correctly.

The misfires are the trigger dolly. It's getting caught in the fall back stage. So have a look at the spring and see if you have anything blocking the dolly. The cut off is resetting, the dolly isn't getting caught in the contacts. So it has to be with the dolly falling back and resetting. Perhaps the spring is weak, or the ways have a burr or tight spot. I'd be tempted to give it a blast of silicone spray to see if it solves it.


 
Hi,

I couldn't see any screw in the bottom of the motor cage, there is a round metal plate between the motor and cage though, maybe if I remove that.

Trigger dolly? Which spring is this, the one at the back? Looks a bit squashed from what I could see and maybe rusted or just dirty. Haven't got any spray, would the clear jelly stuff I bought work? 

 
I couldn't see any screw in the bottom of the motor cage, there is a round metal plate between the motor and cage though, maybe if I remove that.
The screw should push that plate and the motor with it. It'll be a very small grub screw. That is turned with an equally small allen key.

It'll have a hex head in a small hole that looks directly up at where that plate is.

I'd grab some silicone spray with a fine straw nozzle. and just give it a blast in the hole on the back side of the gearbox where you can see the trigger pushing the dolly. Most auto parts stores sell a cheap silicone if you don't want to get the more expensive stuff. Halfords for example should have it. It won't be the best quality spray, but then again your not lubing up a real gun so it's not going to make any difference.

If your lucky it'll solve the issue without needing to open the gearbox again.

http://www.halfords.com/webapp/wcs/stores/servlet/ProductMobileDisplay?catalogId=10151&storeId=10001&productId=219033&categoryId=165705&langId=-1

If the spring is crushed you may need to find another. It might not have the required force, or orientation to pull the dolly back to a well reset position if it's kinked.


Grub screws look like this. You should be able to spot the hexagon internal head part.

socket-set-grub-screw-stainless-steel%20(2).jpg






 

 
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The screw should push that plate and the motor with it. It'll be a very small grub screw. That is turned with an equally small allen key.

It'll have a hex head in a small hole that looks directly up at where that plate is.

I'd grab some silicone spray with a fine straw nozzle. and just give it a blast in the hole on the back side of the gearbox where you can see the trigger pushing the dolly. Most auto parts stores sell a cheap silicone if you don't want to get the more expensive stuff. Halfords for example should have it. It won't be the best quality spray, but then again your not lubing up a real gun so it's not going to make any difference.

If your lucky it'll solve the issue without needing to open the gearbox again.

http://www.halfords.com/webapp/wcs/stores/servlet/ProductMobileDisplay?catalogId=10151&storeId=10001&productId=219033&categoryId=165705&langId=-1



Grub screws look like this. You should be able to spot the hexagon internal head part.







 
Okay cheers I'll get some, I assume that abbey stuff works also. 

As for the screw there isn't one there, could of sworn there was one in the bottom of the stock grip though. May have dissappeared when I took it apart.

Thanks again. 

View attachment 35412

View attachment 35413

 
yeah that is the reason the gearbox sounds the way it does. You need a grub screw.

If you can't find it then you can order a box of them cheap enough from ebay that come with all common small sizes. I think the common size is M3x6 mm. Using a 1.5mm allen key. but I might be wrong as I've never needed to buy one!

A kit like this should cover all bases.

https://www.ebay.co.uk/itm/200PCS-Allen-Head-Socket-Hex-Grub-Screw-Assortment-Cup-Point-Set-Stainless-Steel/323204657748?epid=14018917442&hash=item4b407fb254

Abbey spray would be perfect. It's one of the better quality silicone sprays, so if you have a tin just try a shot in that hole and see if it sorts it.

 
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yeah that is the reason the gearbox sounds the way it does. You need a grub screw.

If you can't find it then you can order a box of them cheap enough from ebay that come with all common small sizes. I think the common size is M3x6 mm. Using a 1.5mm allen key. but I might be wrong as I've never needed to buy one!

A kit like this should cover all bases.

https://www.ebay.co.uk/itm/200PCS-Allen-Head-Socket-Hex-Grub-Screw-Assortment-Cup-Point-Set-Stainless-Steel/323204657748?epid=14018917442&hash=item4b407fb254

Abbey spray would be perfect. It's one of the better quality silicone sprays, so if you have a tin just try a shot in that hole and see if it sorts it.
Alright great I'll have a look around tomorrow for it if not I'll pick them up, will get that spray for sure though.

Once again thanks for the help, really appreciate you taking the time to do so. 

 
It's no problem, Gearboxes are funny bastards. Simple to look at but very easy to get wrong. Even more so when it's your first time tinkering with them. Once you've played with them a couple of times you will wonder why you ever struggled. Because you look at the parts differently, and understand how the fitting works.

 
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It's no problem, Gearboxes are funny bastards. Simple to look at but very easy to get wrong. Even more so when it's your first time tinkering with them. Once you've played with them a couple of times you will wonder why you ever struggled. Because you look at the parts differently, and understand how the fitting works.
Well hopefully that will happen soon as its still pretty alien to me after guiding myself using youtube videos. Changing hop up etc was easier than I thought anyway so I'm sure I'll get there. 

 
It's no problem, Gearboxes are funny bastards. Simple to look at but very easy to get wrong. Even more so when it's your first time tinkering with them. Once you've played with them a couple of times you will wonder why you ever struggled. Because you look at the parts differently, and understand how the fitting works.
Haven't got my grubs screws yet or silicone but trigger seems better now after taking it apart, gearbox still sounds shite.

Tried firing it before as I was going to go to a nightgame but it decided to not fire apart from 5 bbs from a near full mag on auto, doesn't seem to be feeding at all really.

Looks as though the air nozzle is in the way of the bbs getting in chamber? 

Honestly unsure. 

YouTube video below in case attached one doesn't work.



View attachment 35583
View attachment 35584

View attachment 35585

 
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Tried firing it before as I was going to go to a nightgame but it decided to not fire apart from 5 bbs from a near full mag on auto, doesn't seem to be feeding at all really.
Right, well you didn't change the airseal nozzle, so it can't be that, unless the gun has never worked correctly.

The airseal nozzle sits in a groove on the tappet plate, so provided it's on the tappet plate correctly it can't be that.

You did change the gearset. There is a chance that the sector gear has a slightly shorter radius on the nub that pulls the tappet plate back. Is that correctable> yes.

So I take it you didn't throw away the old gears. If you did it's no problem.



Firstly split the gearbox again.

Take the sector gear, tappet plate, airseal nozzle assembly.

Check the sector gear at 9 oclock on the cam is pulling the airseal nozzle and tappet plate all the way back to the cylinder head.

42207223404_f094381793_b.jpg



If that isn't the case try the other sector gear. It might have a bigger cam radius.


If the airseal nozzle is been pulled fully back chances are the airseal nozzle is incorrect and needs to be corrected. So while you have it split measure the airseal nozzle total length. If it was shooting before you stripped it, and now it isn't the airseal nozzle won't of changed length overnight. So if it was shooting before then the issue must be with the tappet plate/sector gear interaction, or there is another issue like the mag isn't feeding well.


 

 
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Right, well you didn't change the airseal nozzle, so it can't be that.

The airseal nozzle sits in a groove on the tappet plate, so provided it's on the tappet plate correctly it can't be that.

You did change the gearset. There is a chance that the sector gear has a slightly shorter radius on the nub that pulls the tappet plate back. Is that correctable> yes.

So I take it you didn't throw away the old gears. If you did it's no problem.



Firstly split the gearbox again.

Take the sector gear, tappet plate, airseal nozzle assembly.

Check the sector gear at 9 oclock on the cam is pulling the airseal nozzle and tappet plate all the way back to the cylinder head.




If that isn't the case try the other sector gear. It might have a bigger cam radius.


If the airseal nozzle is been pulled fully back chances are the airseal nozzle is incorrect and needs to be corrected. So while you have it split measure the airseal nozzle total length.


 
Hi, 

I still have the old gears!

One other thing to note is, I tried putting a screw in the motor cage to act as a grub screw that would fit in, it did and pushed the plate up, kind of went too far and the screw wouldn't go back in.

Opened up the gearbox afterwards and was full of metal shavings, so cleaned that out anyway.

One thing of notice is when I closed the gearbox the bushing on the sector gear wouldn't seem to go through the hole on the gearbox, sits underneath it like it doesn't have enough reach.

I'll trying doing what you said at some point and get back to you.

Getting on my tits this gun! Haha, thanks again.

 
One thing of notice is when I closed the gearbox the bushing on the sector gear wouldn't seem to go through the hole on the gearbox, sits underneath it like it doesn't have enough reach.
Provided the bushing is sat flush on the inside of the shell it won't matter. If it's stuck out into the shell then that will need correcting.

One other thing to note is, I tried putting a screw in the motor cage to act as a grub screw that would fit in, it did and pushed the plate up, kind of went too far and the screw wouldn't go back in.
You may have stripped the threads. The only solution for that is to drill and re-tap it at the next size up. Thread taps are pretty cheap and the materiel is soft so it's a simple project. You may even get away without drilling it.

https://www.toolstation.com/shop/Hand+Tools/d10/Engineers+Tools/sd190/Draper+Tap+%26+Die+Set/p10128

The 4mm tap in that kit will re-thread the screw hole. But you will then need a 4mm grub screw!
 



 
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4 minutes ago, Iceni said:

Provided the bushing is sat flush on the inside of the shell it won't matter. If it's stuck out into the shell then that will need correcting.

You may have stripped the threads. The only solution for that is to drill and re-tap it at the next size up. Thread taps are pretty cheap and the materiel is soft so it's a simple project. You may even get away without drilling it.

https://www.toolstation.com/shop/Hand+Tools/d10/Engineers+Tools/sd190/Draper+Tap+%26+Die+Set/p10128

The 4mm tap in that kit will re-thread the screw hole. But you will then need a 4mm grub screw!
 

Damn, should of bloody left it haha. Oh well that sorts that then anyway and atleast I'll know what screw I need for sure if I do this. 

Thanks again

 
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