Continuing with the M4

[SeniorSpaz87]

Ok,

So... Parts arrived; spend three hours rewiring the thing, heat-shrinking every exposed wire to prevent shorts, and making a mess of my table. Anyway, it now works. Sort of... The connection is good, but when I pull the trigger I get a high pitched whir sound. I immediately stopped trying to fire, and removed the battery so I wouldn't mess anything up. So... Any idea what's up?

[sp00n]

Motor connected the right way round?

Is the motor height set?

[SeniorSpaz87]

Umm, with the motor, does it matter which way it's put in, as long as the wires are correct? And I don't know about the height... How can I check that?

[sp00n]

I should have said, is the motor connected up the right way round?

To be honest you have to listen when setting the motor height, and I am no expert at it

[SeniorSpaz87]

Yea, it's the right way round. I know because the red connector has a red dot on the male end, and there is no female black on mine; it wasn't on when I got it, so it's soldered on instead

[sp00n]

Arrrr no probs there then

 

Dose it fire at all?

[Cheeky vimto]

There's a screw on the bottom of the handle. Wind it all the way out and slowly wind it in, firing every rotation.

[SeniorSpaz87]

Probably not. After I reconstructed it I connected the battery, and when there was no smoke, I tried the trigger as a dry fire. The high pitched whir started, and I stopped the connection after around 1/2 second and removed the battery; I haven't done anything else with it.

[SeniorSpaz87]

There's a screw on the bottom of the handle. Wind it all the way out and slowly wind it in, firing every rotation.

Ahh, so that's what it does...

[Cheeky vimto]

I've had this happen to me before. I found out either my gears weren't meshing right with the piston (AOE), or it wasn't shimmed correctly as the wear wasn't Central on the piston. I double checked shims and added a sorbo pad and corrected AOE and has ran fine since.

 

When I took the gun apart I found the gear and ruined the piston teeth and I needed to get a new one.

[SeniorSpaz87]

Update... Vitmo, that didn't fix it. I tried every position, with the same result. However, I was try into remove the motor to test it, and I can't remove it (although I haven't tried very hard, don't want to break anything). Sooooo.... What have I done now?...

[Cheeky vimto]

Ahh, so that's what it does...

Yea. It basically pushes the motor up to properly mesh with the bevel gear.

[Cheeky vimto]

Update... Vitmo, that didn't fix it. I tried every position, with the same result. However, I was try into remove the motor to test it, and I can't remove it (although I haven't tried very hard, don't want to break anything). Sooooo.... What have I done now?...

 

You mean the motor is stuck in there?

[SeniorSpaz87]

You mean the motor is stuck in there?

It would seem...

[Cheeky vimto]

It would seem...

 

Wiggle it, it'll come out. If you've played with the height on the motor you might of pushed it up too far into the gearbox and jammed it.

[SeniorSpaz87]

Wiggle it, it'll come out. If you've played with the height on the motor you might of pushed it up too far into the gearbox and jammed it.

I was thinking it may have been something like that. I can move it forwards and backup wards, and the spring isn't under too much compression, as I can push it in, in which case it returns to its current position.

[Cheeky vimto]

I was thinking it may have been something like that. I can move it forwards and backup wards, and the spring isn't under too much compression, as I can push it in, in which case it returns to its current position.

Nothing holds the motor in other than the handle cap you've taken off. Try getting some needle nose pliers, wiggle and pull. I suggest taking the whole thing apart. If it's making a 'whirl' sound, your gears may be spinning and just hitting the tip of your piston teeth, eventually destroying it.

[SeniorSpaz87]

Alright, got it out easily. A bit more pressure got it out. And it was more of a grinding; indeed, the gear on the end of the motor has ground down a touch, but not enough to affect it. So do I need to take the damn thing apart again?...

[SeniorSpaz87]

Update; the motor works fine when removed from the gun.

[Cheeky vimto]

It will do if you heard a whirl sound. If there's a bit of grinding on the motor teeth maybe it just needs adjusting on the motor height more or the gears aren't shimmed right and the bevel gear isn't central to the motor. You don't have to take it all apart again but it you keep shooting with grinding noise it might cost you a bit more. It should be easier to see where isn't going wrong if it's griding, just look for wear.

[SeniorSpaz87]

Well, firing right now isn't an option... The issue is defiantly at the connection between the motor gear and the gear it's supposed to sit flush with in the gearbox. But I think my battery's running low, so I'll charge it overnight and continue the troubleshooting tomorrow.