upgrade needs 25amp fuse,why?

glicster

the gears in my ca m4 sportline recently gave in so ive installed new bushings,hop up,piston and a set of high speed gears.i left the spring because its still fireing at a good fps.
ive shimmed,re-shimmed and re-shimmed again and everythings running as smooth as i could get it.put the gb back together,hand grip and motor and gave it a test drive,now the problem starts,

useing the recommended 8.4v battery it fired a couple of times and then stopped and blew the 20amp fuse.opened it up again re-done everything and tested it again,same thing.

i then got a 9.6v battery,gave it a go,fired a few times then blew the fuse.i put in a 25amp and off she went,like a dream.tryed it on the 8.4v again and it wouldnt fully compress the spring.

so it now needs a 25amp and 9.6v to run.
is this because of the high speed gears and will it cause damage to the motor or is it that the motor is on its way out?

everything looks and sounds good when i fire so im sure my work is good but the increase in battery and fuse has me baffled.

wots your opinion on this,cheers lads

Leftyflip

You could have shimmed it too tight actually, I've seen it happen and I did it myself one time. If it's not that then it sounds like the motor may not be adjusted correctly or is on its way out. I'm sure someone else will have more ideas.

glicster

was hoping youd have the solution lefty,its not smimmed tight i can spin gears freely with my finger and theres little to no play in them.the motor is not engaging too tight coz i dont have that noise you can hear when so and ive adjusted it to see if that d problem.
but will it cause any problems pulling more power from d battery

Leftyflip

glicster wrote: »

was hoping youd have the solution lefty,its not smimmed tight i can spin gears freely with my finger and theres little to no play in them.the motor is not engaging too tight coz i dont have that noise you can hear when so and ive adjusted it to see if that d problem.
but will it cause any problems pulling more power from d battery

Actually what type fuses are you using? If they're the fast blow ones, then that could be your problem.

glicster

well that now i dont know,there glass auto fuses.look the same as what came in it.
it doesnt blow 25amps so dats ok and its not my primary so wont see a whole lot of action but just curious,is it ok needing a 25amp or will it burn the hands off me by overheating

Leftyflip

glicster wrote: »

well that now i dont know,there glass auto fuses.look the same as what came in it.
it doesnt blow 25amps so dats ok and its not my primary so wont see a whole lot of action but just curious,is it ok needing a 25amp or will it burn the hands off me by overheating

I use 25 amps fuses in mine, but I've replaced the wiring and all, but it should be ok.

glicster

ill settle with that so,and ye d wires do get a lil warm so that will be something to look into,cheers lefty

Masada

How have ya tested the shimming? I usually remove the piston/cylinder etc and screw the shell back together with just the gears in, then rotate them through the hole where the cylinder was to test they are able to turn over nice and easy.
a common mistake people make is to shim it and test with the shell pressed together, but not screwed. it tightens up ever so slightly when you screw it and that makes a big difference to the shimming.

if thats not the problem and the motor sounds fine, id look at the trigger contact or if it has one, the metal contact under the selector plate.