Strange fault

[Rubberducky]

Got my little brothers mates mp5 A something in bits as when you pull the trigger on full auto it fires and then slows down and just stops like the batteries flat but you plug the battery on another gun and it's fine :s. Put a another battery back on his mp5 and it goes again and then stops again. I've had the box in bits and checked the gears and shimming and its all ok. Annoying thing was I put it all back together last night and it was fine (firing before I left it overnight) got it to work this morning to put a magazine through it and it stops.

Can anyone help?

James

[Rubberducky]

Re: Strange fault.....

Right just taken the gearbox out and the motor pulls the the piston back but once it's back it won't release it.

[richardy]

Re: Strange fault

its not getting enough power to pull the spring back.

either a you increase the power ging to the motor

or b you reduce the work the motor needs to do in order to compress the spring and rtate the gears.

[jagillham]

Re: Strange fault

c) The motor could be shot?

[richardy]

Re: Strange fault

yup, would be my first place too look, comes under both a and b really. well my first place would be shimming, then wiring then motor. dispite whats been previously done to the gun.

some times a motor can spin fine when connected but simply cant produce any power to turn the gun over when installed.

[Rubberducky]

Re: Strange fault

Looks like it was the chinasoft spring he installed to get more umph! Removed it and it's running a dream. Thanks for the help guys.

[richardy]

Re: Strange fault

theres a basic amount of space inside the gearbox, between the piston head and spring guide. theres many ways of making a spring to produce x amount of power, some times the compressed coil length is too long for the space available. you dont "need" bearings on piston heads and spring guides removing these can often gain you some extra space.

[Rubberducky]

Re: Strange fault

Yeah I know where your coming from. Not seen a bearing on a piston head though? I'm guessing their only on the upgraded ones?

[richardy]

Re: Strange fault

yup although even on a tm one the weight on the back of the piston head takes up a certain anmount of space and is designed to add a bit of extra weight. The spring should have been designed on at least that kind of piston head thoough..

it could be another problem which was simply uncovered by the spring. but hey if its working job done.