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Mouse
07-21-2003, 10:14 PM
My friend's M733 blows a fuse everytime you squeeze the trigger. Sometimes it will cycle through a few shots...sometimes its almost instant....a sudden spark and thats it.

I am seen various threads on what to do in this case, but i believe they were deleted because they were old or for whatever other reason.

How can i fix this? Would switching to a different AMP fuse (other than the 15 AMP one that its blowing out?) do the trick? I also remember hearding that some of you airsoft gods out there totally remove your fuses for whatever reason. I don't know if that has any relevance (sp?) here, but if that would do the trick let me know.

Thanks in Advance,
William:)

AustinWolv
07-21-2003, 10:38 PM
There is no reason to remove the fuse, unless you want to remove the one safety device on your AEG that will hint to you when something is wrong.

Blowing fuses is that sign that something isn't right. It could happen for a few different reasons, such as poor gear shimming, bad tolerances in the parts, the motor isn't installed correctly into the pistol grip, or the motor is jammed up into the mechbox too tightly. I'm sure others will chime in with some other possibilities as well.

On upgraded guns (400fps, such as those that follow the TASO rules), a 15A fuse is still adequate to do the job. However, going to a 20A fuse won't hurt you.

Some further details might be helpful, and if in doubt, just politely ask someone like Obsidian or Agrovale to take a look at it.

Agrovale
07-22-2003, 08:28 AM
Wolv hit the nail on the head. Ocasionally on my AUG the fuse will blow when the battery is 'dumping'. But I have 15A fuses in all of my guns and they all have M120 springs. If the fuse blows, something is wrong.

Obsidian
07-22-2003, 08:29 AM
ya knowing if someone was into the mechbox was helpfull

Agrovale
07-22-2003, 08:56 AM
Some people remove the fuse under the impression that it will gove them more power and let the battery last longer. Yes, a fuse adds resistance to a circuit, but that resistance is virtually zero. Removing the fuse is a crutch. It will lead to bigger and more expensive problems down the road.

Obsidian
07-22-2003, 11:10 AM
I have removed the fuse on some of my guns because it takes up space and removes a free chance for me to upgrade my guns :)

Mouse
07-22-2003, 01:28 PM
Yes, the gun has been upgraded to 400 fps. (Done by Obsidian or Agrovale.) I forgot to mention that the problem occured when one of the wires fell out of the motor randonly. We popped it open and we couldn't get the wire back in, so we had to pull the motor out to make it easier. (The wire that fell out was jammed on the other side of the motor and couldn't reach around to be plugged back in.)

Becaue of Austinwolv's post, i am pretty sure it is a problem with how the motor is situated in the handgrip.

Anyways thanks for the help, i will post again if the problem complicates itself.

William:)

AustinWolv
07-22-2003, 01:43 PM
You basically need to ensure that the motor will freely move up and down in the pistol grip. Having the wires routed incorrectly will cause it to get caught in one position (usually jammed down at the bottom).

Deliverator
08-16-2004, 09:38 AM
Blowing fuses is that sign that something isn't right.

I just recently upgraded my stock spring in my AUG to an M120S spring. After I got my batteries (8.4v 600mAh) in and charged them up, I put one into the AEG and pulled the trigger. I got maybe 3 or 4 shots off before the motor started making sounds like the batteries were dying (not being able to crank back the spring anymore, slow response, etc.). I opened up the butplate to remove the dead battery and was greeted with the smell of ozone. I checked my fuse and sure enough it had blown.

When we were upgrading the gun, we ensured that all the gears were in the right place, well greased, and operating smoothly before we closed the thing all up. So I guess my question is, what do you guys think may be the problem?

AustinWolv
08-16-2004, 10:10 AM
8.4v 600mAh That is your first problem. There just isn't enough battery capacity to drive a M120 spring for very long, if at all. Since it doesn't have the power to supply the motor, the motor can't pull that spring back, thus it is just sitting there drawing whatever current that mini battery can supply, which can cause the fuse to blow. Typically, I'll use 2000mAh packs with M120 (or equivalent) upgrades, and that will last a usual skirmish day. Go try a 8.4v, 2000mAh pack and give it a try. If you still blow fuses with a large battery pack, then there is likely a gear shimming issue.

Any extraneous friction will cause that battery to die even more quickly (or blow fuses if the friction is that great). That friction is likely the gears having too many shims on them, so they aren't spinning as freely as you think. When you have each individual gear in place in the mechbox, there should be some slight movement allowed side-to-side. Basically, just a couple tenths of a millimeter is good. My personal method is that I check, shim, check, and reshim each gear individually, starting with the sector gear. Assemble the mechbox shell halves together for each respective gear, and then reach in through the cylinder hole to spin them, and they should spin freely well after you gave them that spin.

Then, assemble all the gears in, and again assemble the halves and reach in to pin the sector gear. All the gears should spin freely with minimal noise. Any weird sounds are an indicator of improper gear mesh, so take a look in there to see how the teeth are lined up.

From there, just grease it up, assemble it all back together, and you should be good to go.

If one gear isn't spinning freely ever, then the bushing might be deformed or the hole too tight in it. I've gotten some that way, where the hole inner diameter is too tight for the gear axle. Take some sandpaper and try to "grow" the hole a bit, or better yet, get a different bushing, as that one is bad juju.

Apply some lube on the guide rails of the mechbox shell for the piston as well.

Deliverator
08-16-2004, 11:02 AM
thanks a lot Wolv. I really appreciate it. I'll try a larger battery and see if that doesn't fix the problem. As far as I can remember, the gears were exactly as you described they should be, so unless they got knocked around more than appropriate when I was wrestling that spring back into the box, everything should be ok, hehe. Thanks again for your help.

Deliverator
08-16-2004, 11:12 AM
This (http://www.onlybatterypacks.com/showitem.asp?ItemID=10077.11) is a battery I found at Onlybatterypacks.com (http://www.onlybatterypacks.com/showitem.asp?ItemID=10077.11). Would this be sufficient but at the same time fit in my AUG? I'm a little unfamiliar with the modificiation necessary to fit the larger style batteries in to my AUG, that's why I'm asking this question, hehe.

AustinWolv
08-16-2004, 11:14 AM
Agrovale could answer the AUG battery question better than I.

Obsidian
08-16-2004, 11:40 AM
Yup thats what I used in all my AUGs. Using that Pack might require a bit of modification or rerouting of the wires to get it to fit. Another option that many people have taken up is getting a strip of velcro and sticking a Large battery on the flat side of the stock. Then all you have to do is notch the butt plate and run the wire out.

Deliverator
08-16-2004, 11:49 AM
cool, thanks Obsidian. Do any of you guys know if there's been a "How-to" written about modding the stock so the large batteries will fit inside the gun?

Deliverator
08-19-2004, 08:38 AM
well, i apparently screwed up my gears or bushings when i upgraded the spring myself. just tried my AUG with a 9.6 1500mAh battery and it still blew the fuse. any suggestions?

AustinWolv
08-19-2004, 08:47 AM
Open her back up and check the shimming. ;)

Agrovale
08-19-2004, 08:54 AM
This (http://www.onlybatterypacks.com/showitem.asp?ItemID=10077.11) is a battery I found at Onlybatterypacks.com (http://www.onlybatterypacks.com/showitem.asp?ItemID=10077.11). Would this be sufficient but at the same time fit in my AUG? I'm a little unfamiliar with the modificiation necessary to fit the larger style batteries in to my AUG, that's why I'm asking this question, hehe.

Those are the exact batteries I use in my AUG. The only thing I had to do to get them in there was to relocate the fuse to the other side of the black plastic plate (the one that holds the mechbox in).

Deliverator
08-19-2004, 09:32 AM
Open her back up and check the shimming. ;)

damn...that thing was a bitch to close back up with that 120 spring in there...

*not looking forward to this prospect at all* :(

thanks for your help guys.

i'll be borrowing Artex's MP-5 for this Op since i don't have the time to spend on my AUG.

AustinWolv
08-19-2004, 10:23 AM
Bring the AUG down, and if you're flexible, I'm sure one of us could take a look at it if you like. Just not during the op. ;)

Deliverator
08-19-2004, 11:03 AM
sure thing. i'll haul it down there, myself and the rest of Wolf Pack are staying at the Red Roof Inn on I-35 in South Austin, just FYI. i'll be borrowing Artex's AUG instead of his MP-5, so fixing my AUG before the Op is low priority, just as long as it's working before the next Op, hehe.