G3 Mechbox Cycle issue

Cobrajr122 · March 25th, 2011, 20:03

OK, after battering Amos and Dark Angel over TS/MSN for a good 2.5 hours we have not come to a solid solution other then possibly bad shimming, which I am sure is fine...

So here is the issue.

Up until today, the box was working fine, I opened it up to put in a new lower powered spring. Put the box back together and went to test fire and that when the fun began.

Basically what is happening is in semi mode, the gear is cycling a bit past the point where the cut off leaver engages and end up holding the nozzle back, the way the gun then continues to cycle stops the bbs from firing consistently, and has killed the air seal - otherwise - useless in semi, the ONLY MODE I USE >:(.

After numerous tests, Its been determined that the cut off leaver IS engaging and separating the contacts. The sector gear cannot be moved until the trigger is released and pulled again. but as soon as I assemble everything again it fucks up.

The pic shows where it is stopping. The nozzle and tappet plate are fully to the rear, it cannot be pushed in or be pulled out at all.

Hopefully somebody can help me out on this :S

audi_bhoy · March 25th, 2011, 21:47

Have you tried putting the stronger spring back in? The motor could be overspinning in semi mode, happened to me before I install a MOSFET as my motor had so much torque it would start a new cycle when firing semi.

Cobrajr122 · March 25th, 2011, 22:02

Quote:

Originally Posted by audi_bhoy

Have you tried putting the stronger spring back in? The motor could be overspinning in semi mode, happened to me before I install a MOSFET as my motor had so much torque it would start a new cycle when firing semi.

I have tried this, nogo, still over cycling.

I am glad I am not the only one that thought of that XD

onpoint · March 25th, 2011, 22:38

are you using a lipo?

DarkAngel · March 25th, 2011, 23:02

Hes using a 9.6

Jayne Finch · March 26th, 2011, 00:14

ok. so from what i understand the piston is being held back by the sector gear over rotating on each cycle, causing it to draw the piston back prematurely?

dumb question: same battery you were using before right?

Cobrajr122 · March 26th, 2011, 00:29

Quote:

Originally Posted by Jayne Finch

ok. so from what i understand the piston is being held back by the sector gear over rotating on each cycle, causing it to draw the piston back prematurely?

dumb question: same battery you were using before right?

Yes, same battery.

Both the piston and the tappet plate(and therefor nozzle) are being drawn back prematurity.

pokey · March 26th, 2011, 00:48

Sector gear shimmed to high causing binding with the tappet?? Maybe a shim was mistakingly put on the bottom side of the gear when reassembled? Does the tappet and nozzle move freely before you try to cycle the gearbox?

Jayne Finch · March 26th, 2011, 01:05

well thats a new one isnt it?

i wonder if the cut off lever isnt functioning fast enough. check it and the teardrop on your sector gear for wear on all contact points including the pivot of the cut off lever.

@ pokey:
i doubt thats the issue. jamming would cause under rotation. the problem here is over rotation

HKGhost · March 26th, 2011, 01:09

My guess is because you installed a lighter spring, there is less resistance so the motor will over spin. Now if you still have the same problem with the original spring, that just means your gearbox is shimmed nicely and has very little resistance. To me, having a little over spin is good as your next shot will be faster because of the precocked. Also, is the second last tooth on your piston removed?

Cobrajr122 · March 26th, 2011, 01:13

Quote:

Originally Posted by HKGhost

My guess is because you installed a lighter spring, there is less resistance so the motor will over spin. Now if you still have the same problem with the original spring, that just means your gearbox is shimmed nicely and has very little resistance. To me, having a little over spin is good as your next shot will be faster because of the precocked.

As positive as this sounds, its is an issue because in my case the nozzle is not staying forward long enough to get a good seal and shoot the BB.

Quote:

Originally Posted by HKGhost

Also, is the second last tooth on your piston removed?

It is not.

Quote:

Originally Posted by pokey

Sector gear shimmed to high causing binding with the tappet?? Maybe a shim was mistakingly put on the bottom side of the gear when reassembled?

It was just a quick spring change. The gears were not removed, bushings and shims were left in place during the whole procedure.

Though this was brought up during my trouble shooting, so I removed 1 shim from the bottom of the sector gear and spun it around a few times with some very bad grindy noises lol, so i replaced the shim and everything was smooth and quiet again.

Quote:

Originally Posted by pokey

Does the tappet and nozzle move freely before you try to cycle the gearbox?

They do.

HKGhost · March 26th, 2011, 01:17

so it seems you have a premature engagement problem. Remove the second last tooth from the end of the piston. And half of the third tooth from the same end.

pokey · March 26th, 2011, 01:17

Quote:

Originally Posted by Jayne Finch

well thats a new one isnt it?

i wonder if the cut off lever isnt functioning fast enough. check it and the teardrop on your sector gear for wear on all contact points including the pivot of the cut off lever.

@ pokey:
i doubt thats the issue. jamming would cause under rotation. the problem here is over rotation

Ah! fair enough, I read wrong. I does seem as though its getting too much juice though. Look into the electrics and cutoff mechanism as Finch has said.

CJay · March 26th, 2011, 01:21

next question - what make is the gearbox - I recall having this same issue with 4 KWA G36's this year alone already and in every case the cyllinderhead shaft had become loose and disengaged mostly but not all the way from the seating - I'd be checking that to make sure it's solid - have the same probs with alot of the cansoft M4's that KWA makes as well.

Cobrajr122 · March 26th, 2011, 01:25

Quote:

Originally Posted by HKGhost

so it seems you have a premature engagement problem. Remove the second last tooth from the end of the piston. And half of the third tooth from the same end.

I don't believe this is the problem as AOE is good. That and if the sector gear was stooping where it is supposed to, the tappet plate would not be pulled back.

I will play around with AOE again though just to make sure.

Quote:

Originally Posted by CJay

next question - what make is the gearbox - I recall having this same issue with 4 KWA G36's this year alone already and in every case the cyllinderhead shaft had become loose and disengaged mostly but not all the way from the seating - I'd be checking that to make sure it's solid - have the same probs with alot of the cansoft M4's that KWA makes as well.

TM

Only non TM parts are the Cylinder head, Piston head, spring and spring guide.

Home	Forums	Register	Gallery	FAQ	Calendar
Retailers	Community	News/Info	International Retailers	IRC	Today's Posts

British Columbia	Alberta
BCAC	EAR
Op-For	JOC
Northern Arms Airsoft	Skunkworx Airsoft
Airsoft Kelowna	RAAT
Prince George Airsoft	Manitoba
Saskatchewan	MAA
SK Airsoft	Ontario
PDW	Airsoft Ottawa
South Sask Mercs	Snow Dragons
Quebec	1st Ranger Platoon
PQAC	Wolfpack Tactical
1st Pathfinders Regiment	TTAC3
Quebec Airsoft
MTX Airsoft	Atlantic
FAQc	Atlantic Airsoft

March 25th, 2011, 20:03	#1
Cobrajr122 2 Cent Tactical Trader rating Join Date: Apr 2006 Location: NB	G3 Mechbox Cycle issue OK, after battering Amos and Dark Angel over TS/MSN for a good 2.5 hours we have not come to a solid solution other then possibly bad shimming, which I am sure is fine... So here is the issue. Up until today, the box was working fine, I opened it up to put in a new lower powered spring. Put the box back together and went to test fire and that when the fun began. Basically what is happening is in semi mode, the gear is cycling a bit past the point where the cut off leaver engages and end up holding the nozzle back, the way the gun then continues to cycle stops the bbs from firing consistently, and has killed the air seal - otherwise - useless in semi, the ONLY MODE I USE >:(. After numerous tests, Its been determined that the cut off leaver IS engaging and separating the contacts. The sector gear cannot be moved until the trigger is released and pulled again. but as soon as I assemble everything again it fucks up. The pic shows where it is stopping. The nozzle and tappet plate are fully to the rear, it cannot be pushed in or be pulled out at all. Hopefully somebody can help me out on this :S __________________ www.2centtac.com F i n d - a n - A g e - V e r i f i e r

March 25th, 2011, 23:02	#5
DarkAngel * Age Verifier status suspended * Trader rating Join Date: Jun 2006 Location: Scarborough	Hes using a 9.6 __________________ Certified Sniper Clinic Instructor and Counter Sniper Sentinel Arms Customs - Specializing In Unique, One of a kind guns

March 26th, 2011, 00:14	#6
Jayne Finch Trader rating Join Date: Apr 2007 Location: my field mostly. seems that way at least.	ok. so from what i understand the piston is being held back by the sector gear over rotating on each cycle, causing it to draw the piston back prematurely? dumb question: same battery you were using before right? __________________ -------------------------------------------------------- "bitches don't know 'bout my killing zombies!" "Be polite. Be professional. But, have a plan to kill everyone you meet." "i don't have a license to kill. but i have a learners permit!" Last edited by Jayne Finch; March 26th, 2011 at 00:18..

March 25th, 2011, 21:47	#2
audi_bhoy Trader rating Join Date: Mar 2009 Location: Trois-Rivières	Have you tried putting the stronger spring back in? The motor could be overspinning in semi mode, happened to me before I install a MOSFET as my motor had so much torque it would start a new cycle when firing semi.

March 25th, 2011, 22:38	#4
onpoint Trader rating Join Date: Jan 2009 Location: scarborough	are you using a lipo?

March 26th, 2011, 00:48	#8
pokey Trader rating Join Date: Apr 2004 Location: SasKat00N, SK	Sector gear shimmed to high causing binding with the tappet?? Maybe a shim was mistakingly put on the bottom side of the gear when reassembled? Does the tappet and nozzle move freely before you try to cycle the gearbox?

March 26th, 2011, 01:05	#9
Jayne Finch Trader rating Join Date: Apr 2007 Location: my field mostly. seems that way at least.	well thats a new one isnt it? i wonder if the cut off lever isnt functioning fast enough. check it and the teardrop on your sector gear for wear on all contact points including the pivot of the cut off lever. @ pokey: i doubt thats the issue. jamming would cause under rotation. the problem here is over rotation __________________ -------------------------------------------------------- "bitches don't know 'bout my killing zombies!" "Be polite. Be professional. But, have a plan to kill everyone you meet." "i don't have a license to kill. but i have a learners permit!" Last edited by Jayne Finch; March 26th, 2011 at 01:08..

March 26th, 2011, 01:09	#10
HKGhost Trader rating Join Date: Nov 2009 Location: Mississauga, ON	My guess is because you installed a lighter spring, there is less resistance so the motor will over spin. Now if you still have the same problem with the original spring, that just means your gearbox is shimmed nicely and has very little resistance. To me, having a little over spin is good as your next shot will be faster because of the precocked. Also, is the second last tooth on your piston removed? __________________ Please email me as I'm not on ASC too often. Custom Build \| Upgrades \| Repairs \| Maintenance Contact: ghostgunwork@gmail.com / Private Message

March 26th, 2011, 01:17	#12
HKGhost Trader rating Join Date: Nov 2009 Location: Mississauga, ON	so it seems you have a premature engagement problem. Remove the second last tooth from the end of the piston. And half of the third tooth from the same end. __________________ Please email me as I'm not on ASC too often. Custom Build \| Upgrades \| Repairs \| Maintenance Contact: ghostgunwork@gmail.com / Private Message

March 26th, 2011, 01:21	#14
CJay Trader rating Join Date: Oct 2008 Location: Belle River, ON	next question - what make is the gearbox - I recall having this same issue with 4 KWA G36's this year alone already and in every case the cyllinderhead shaft had become loose and disengaged mostly but not all the way from the seating - I'd be checking that to make sure it's solid - have the same probs with alot of the cansoft M4's that KWA makes as well. __________________ "Creator of the Zombat Sniper - oh yeah baby"

G3 Mechbox Cycle issue

Doctor's Corner