Ca M15A4 CQB + Systema 150 Gearbox

[moto]

I picked up a Systema 150 gearbox for my CA M15A4 CQB. Something is wrong and Im not too sure what it could be. The rest of my setup consists of the stock motor and 9.6v 3300mah nimh batteries.

Basically the when I pull the trigger, I get a quick wirrrr sound like its working but then it just stops. The cycle doesnt complete, it just stops somewhere in the middle of the cycle. If I remove the grip and motor and try to cycle the gears by stocking a small screwdriver in the opening, the gears seem very tight. I would think this is normal as it is half way through the firing cycle and there is a significant amount of tension brought on by the partly compressed spring.

Ive been working on this for a few days now and Ive exhausted all my ideas. I have opened the gearbox and inspeced the parts and movements but everything seems fine. I should also mention that I have tried a Systema Magnum Turbo motor because I thought maybe the stock motor wasnt strong enough but it didnt solve the problem. Any ideas are appreciated.

Thanks

[Jugglez]

Have you tried another battery?

[moto]

I have not tried another battery. I know this battery is in great shape I was just using it in the rifle before the upgrade.

Note: Removing the motor from the gearbox (letting it spin without resistance) and pulling the trigger resulted in normal operation but ofcourse putting it back in resulted in the same issue.

[thephenom]

For a SP150 spring, don't you usually need torque up gears and motor to turn that heavy spring?

[Kid]

Originally Posted by thephenom

For a SP150 spring, don't you usually need torque up gears and motor to turn that heavy spring?

SystemA 150 'Mechabox' is made for this setup (internals already in).

[safx]

I've had a couple 375fps+ M4's and no nimh batteries could properly cycle the heavy springs I was running. Trying to crank the spring on a nimh would usually get 1-2 cycles max and or stop in the middle of one. Of course the motor would still run fine when powered by the little battery, but a NICAD was the only thing that would produce the juice to run my guns normally.

Try a large NiCd battery, the max you can get your hands on.

I'm building an MP5 around a Systema Magnum 170 set, and I'll need a 10—12v for that... but I'll be downgrading it 400fps to safely shoot my pals

[Denis[teamplayer]]

maybe its the position of the motor, too far in and tight perhaps.

edit: also check and see if the piston slides smoothly on the grooves of each gearbox wall, go through each part involved and inspect it.
- possible the spring is extra long, restricting it from cycling fully?

[Kid]

Before you try anything else... I think you should give a try at a different battery. You said everything looks good inside, and is in fact a huge spring to pull.

[moto]

Well.. I just finished testing the mechbox with a 120 spring and it cycled fine. I have a hard time with the fact that it could be the NiMH batteries because at 9.6v it should be enough. I realize that NiCAD have a slightly higher voltage per cell but I would think at 8 cells, NiCAD or not, that it would be enough voltage to turn that spring. Guess Ill pick up a NiCAD and try it out. With this being a DMR, I guess that the higher mah that NiMH delivers is not as important as the extra voltage NiCAD will give me as I wont be unloading strings of BBs.

I picked up a full stock so I guess I need a new battery anyways.

[Death March]

I had the same problem when I up-graded my ICS with the MA-56 upper gear box and it has a M120 spring,all my MiMh batterys were unable to turn it over,but as soon as I put a 9.6 2200 mAh battery in,it shoots all day now!

[swatt13]

Originally Posted by safx

I've had a couple 375fps+ M4's and no nimh batteries could properly cycle the heavy springs I was running. Trying to crank the spring on a nimh would usually get 1-2 cycles max and or stop in the middle of one. Of course the motor would still run fine when powered by the little battery, but a NICAD was the only thing that would produce the juice to run my guns normally.

Try a large NiCd battery, the max you can get your hands on.

ditto! it sounds like your battery. i would definatly get a larger mah and get a 9.6 (i had a 9.6 3600mah ant that worked great). also a hitorque motor would help drastically as it uses less juice to produce more power.

[brently0725]

Nice gun

[Denis[teamplayer]]

Originally Posted by swatt13

ditto! it sounds like your battery. i would definatly get a larger mah and get a 9.6 (i had a 9.6 3600mah ant that worked great). also a hitorque motor would help drastically as it uses less juice to produce more power.

he said in the first post, he has a 9.6v 3300mAh
the spring he has, I would guess needs at least 10.8v (if that's too much, then a magnum motor should help with the batt he has now)

[moto]

As I stated... I have 9.6v 3300mah NiMH batteries and I did try it with a Systema Magnum Turbo motor. I realize its not the High Torque Magnum but it still has better torque then any stock motor, I believe. After replacing the spring with a 120 and cycling the gearbox without issue.. I can only surmise that for some reason my batteries are not suited for this application. I just find this very hard to accept.

I may as well pick up the high torque magnum and add a cell or two now. Meh.. what-the-who... its just more toys.

[Nervikaire]

What is the discharge rate of your battery? ... That is the only real answer you'll need. You could cycle a 400 fps/M120 setup with a 8.4V battery, so a 9.6V can easily cycle an M150. Just get a 9.6V battery with a 30amp discharge rate and dean's connectors. You'll be fine. (you'll be fine, but with an M150 setup, your opponents prolly won't feel the same way... but I guess it's none of my buisness since i'll prolly never play against you :P )