Ak Burst Problem

[Skara]

F

Shimming takes some time, as for the selector, no clue

 

[Sitting Duck]

think I need to reshim  the box again as it got a  little grindy

also the nozzle doesn't always come back after firing on semi  and  the selector doesn't seem to lock into safe properly

shimming is a pita that you get better at the more you do it (hopefully)

there's loads of tutorials how to do it & some good/bad

a bit loose is better than bit tight

yes you kinda start with bevel to pinion but also attention to how the sector is shimmed

(roughly half/half spaced but attention it operates but no rubbing on COL or too high sector cam rubs on box casing)

plus attention to how the spur shims to both sector (swirl pattern if too close)

and attention to ensure plenty of bevel's 10 teeth mesh to spur etc...

(if bevel shimmed high & spur really low, little of 10 teeth mesh and stuff flies off or crunches under stress or mild lock up

so shimming is all about the spacing of gears/drivechain and how all the components engage as close to perfection as possible

(not always very easy to achieve)

IF you was on bushings I'd say a ROUGH BALL PARK...

Bevel - 0.2mm shim on top, no biggy about underneath

really not a massive biggy on JUST this gear underneath coz motor pinion ensures it ain't going far

(if you got a small shim left at end then take up some of slack if you wish to)

Spur/Step gear 0.2mm UNDERNEATH

(whatever is required on top to take up most of slack)

Sector gear 0.25mm to 0.3mm roughly so it sits a whisker higher than spur

(hopefully avoiding swirls from gears touching in rotation)

whatever on top to take up slack, should sit about half way spaced in box for sector gear

as you got bearings it is likely you might have a bit more lateral play than on bushings so add 0.05 to 0.10mm to these ref points

THE ABOVE IS ONLY A VERY ROUGH STARTING POINT, you have to adjust shit accordingly as each box & gears/build vary loads

check motor height with bevel in top half of box

on v3's a bit of shrill can be reduced by loosening the motor cage and slightly shifting it, tilting the motor angle slightly to mesh smoother

nozzle not returning - uhmm it doesn't always return 100% anyway in most instances

the nozzle begins to retract before the piston starts to retract & often the gun's cycle is slowed/stopped by piston retraction or rather the tension on spring building and slowing the motor

which means theif  nozzle often is at least partial retracted or even starting to release if running quick

(and on guns with plenty pre-cock the nozzle has returned already in preparation of firing/piston releasing)

so this nozzle fretting is not a big issue in "most" new tech concerns

obviously if it isn't operating or jamming then that is another issue but nozzle position is not (usually) a big concern

select linkage and stuff - yeah they are a bit of wank

safety is that triangle tab on gearbox that jams the 2 part trigger

the linkage is a git to get correct if the rear teeth are not aligned correctly

(and stay in place as you try to drop the whole thing back in receiver)

also clean & lightly grease and parts of selector/linkage checking they glide as smooth as silk

if any burrs, smooth them out and ensure it all glides/operates smooth as silk

stiff operation on selector mechanism shit will just mean more wear in linkage/selector components sooner

massive tip - take photo's on your phone - LOTS OF PHOTO's

then you will see how shit goes back together

in particular if a certain spring or component goes face down or face up

eg: a trigger trolley spring (you don't have one on etu) on reg setup v2 especially

can make a difference which way round the body of spring is placed or its orientation

(in the way the spring sits to clear the groove in the underside of tappet plate etc...)

on selector mechanism at rear - mark it with a pencil to ensure the marks re-align on assembly

or other shit like that - just a couple of examples

you takea pic or three will greatly assist in reassembly

 

[strykerles]

after the 5th attempt i believe I now have the shimming right

only problem now seems to be with the fire selector, sometimes it won't lock properly into safe and will click into auto when i pull the trigger

if i remove the dust cover it then allows the lever to go a bit higher and it's fine

sometimes too if I go from safe to auto it fires fine, then I go to semi and fire it's fine but then i go back to auto and it only fires in semi

I'm beginning to consider throwing this gun down the garden ?

 

[Sitting Duck]

Linkage issue, likely one tooth out or wear

On a reg V3 there is the tab that locks the trigger solid

The iffy semi/auto is a common problem on AK's

Where linkage is worn or not quite correctly located

(It "could" be one tooth out on rear linkage

Or something is binding when box is refitted into receiver impeding its operation)

Investigate further, likely something stupid out of whack on reassembly

 

[Will-CS]

Just had this 'burst fire' issues on my G&G RK74-E.

The issue was the cut off leaver was in the incorrect position when I put the gearbox back together. When I made the adjustment both single and auto worked without any other work.

Just wanted to put there here in case anyone else has the same issue in the future!