16 replies to this topic

[ElasticShot]

So I bought an Sr-7 from Evike during the Thanksgiving 20% off sale and never fielded it until this morning at a private party at Tac City.  It still has the factory gearbox seal but it's way past the warranty date so I can't return it to the factory. It's running on an Echo 1 11.1v mini lipo (http://www.airsoftgi...roducts_id=7338)  it worked fine for light target shooting, maybe 50 rounds at the max but when I took it to Tac City and actually used it, the rof dropped significantly before it died out on me completely.  Finally got home to check it out, I took the motor out of the pistol grip and plugged the motor connectors into the motor and pulled to trigger to see whether it was a wiring or a motor problem but the motor spun significantly slower than any motor I've ever seen.  Just to make sure it wasn't a wiring problem, I grabbed a motor out of an Echo 1 I had lying around and did the same thing and the motor spun like normal.  I know it was a lipo and there are added risks of running it but I was playing on semi most of the time and it was only one game.  And this battery was on the 3rd party compatibility test with kwa tested so I thought it was be fine to use.  How does a motor burn out anyways?

I've owned a KWA M16BR 1st gen, KWA M4ris 2nd gen, SR12 2nd gen, Sr7 2nd gen, MP9R and an ATP and I've run into problems with all of them accept for the 1st gen m16 and the atp.  I'm not trying to bash KWA, I love the quality and build of these things, they're monsters but I've just gotten bad luck with these things.

What motor do you guys suggest I use for a replacement?

[ElasticShot]

Oh and I've tried multiple 9.6 batteries with the same results

[gcw360]

ElasticShot, on 18 March 2012 - 07:03 PM, said:

So I bought an Sr-7 from Evike during the Thanksgiving 20% off sale and never fielded it until this morning at a private party at Tac City.  It still has the factory gearbox seal but it's way past the warranty date so I can't return it to the factory. It's running on an Echo 1 11.1v mini lipo (http://www.airsoftgi...roducts_id=7338)  it worked fine for light target shooting, maybe 50 rounds at the max but when I took it to Tac City and actually used it, the rof dropped significantly before it died out on me completely.  Finally got home to check it out, I took the motor out of the pistol grip and plugged the motor connectors into the motor and pulled to trigger to see whether it was a wiring or a motor problem but the motor spun significantly slower than any motor I've ever seen.  Just to make sure it wasn't a wiring problem, I grabbed a motor out of an Echo 1 I had lying around and did the same thing and the motor spun like normal.  I know it was a lipo and there are added risks of running it but I was playing on semi most of the time and it was only one game.  And this battery was on the 3rd party compatibility test with kwa tested so I thought it was be fine to use.  How does a motor burn out anyways?

I've owned a KWA M16BR 1st gen, KWA M4ris 2nd gen, SR12 2nd gen, Sr7 2nd gen, MP9R and an ATP and I've run into problems with all of them accept for the 1st gen m16 and the atp.  I'm not trying to bash KWA, I love the quality and build of these things, they're monsters but I've just gotten bad luck with these things.

What motor do you guys suggest I use for a replacement?

Before I address the motor issue, which I think is an easy fix by the way, let me ask you what other issues you have had with KWAs?  Were they motor issues?  Or other unrelated issues that would be best served on a separate thread?

Regarding the motor, remove the brushes, clean them with steel wool, a file, or other tool and reinstall.  I'm betting if you get the carbon off and properly redress them your issue will be resolved.  I use a semi-circular fine file.  I've done the same repair to 3 KWAs (New), one Sytema Magnum, and 15 or 20 G&G Combat Machine stock motors (New).  It's not just KWAs that have this issue cropping up.

[ElasticShot]

The issues were unrelated and I had them fixed over time.  KWA customer service also helped me out in a few of those cases. Customer service is superb which is why I only buy their products.

Thanks, I will try it later and get back to you with the results.

[AciDeX]

Here's a really good tutorial that Killbucket made on cleaning the brushes in your motor. http://airsoftpacifi...hp?f=13&t=20329

[superfrog]

Well actually, you can send it back for repairs but not under warranty.  
And maybe this doesn't need to be stated but ALL aegs even kwa's have issues from time to time.  But, use most people know my kwa has outdated several other guns I've owned, but I have only had two issues in a year.

It's not bad luck, its just man made.

[jpip]

Should brush cleaning be routine, semi-periodic, or only when necessary? What are some signs that they may need to be cleaned? Can the average joe do this easily without screwing something up?

thanks

[superfrog]

Regular maintenance? Prob not, but if the symptomatic of the op come up, then look at it.  Average joes can do this as well as johns, Keith etc.  Not much to screw up.  Just pay attention and your good to go.

[AciDeX]

Like superfrog said, I wouldn't clean the motor brushes on some routine. If you notice motor speed is slowing down or some wacky ROF issues then it would be a good time to try it. However if you had a big game or Operation coming up and you have never cleaned the brushes then it might be a good idea.

Just follow the instructions on the AP link I posted. It's pretty easy, Average Joe, Tom, d*ck and Harry can do this.

[niko_gpsy]

Allizard, on 19 March 2012 - 03:38 PM, said:

I'm wondering if the motor brush spring is not sitting on the correct position.

That is an issue I have had with other brands as well where the spring was not seated correctly and was not pushing against the brushes.  And reseating the spring after cleaning may have inadvertenly solved the issue.

[ElasticShot]

The inner shaft seems to have some carbon build up or what I believe it is.. it's black on the cylinder inside and is sparking when it spins. Is this normal?  Is there a tutorial on how to get to it so I can clean it up?  Or is that the eraser part from the link above?

Edited by ElasticShot, 20 March 2012 - 05:16 PM.

[AciDeX]

ElasticShot, on 20 March 2012 - 05:14 PM, said:

The inner shaft seems to have some carbon build up or what I believe it is.. it's black on the cylinder inside and is sparking when it spins. Is this normal?  Is there a tutorial on how to get to it so I can clean it up?  Or is that the eraser part from the link above?

Yes, glue a chunk of pencil eraser to a kebab skewer and stick it in the hole that the motor brush sits in and spin the motor by hand until the shaft is clean.

Sparks coming off the motor is not good and may be more serious of a problem that cleaning might not be able to fix. You may need a new motor entirely. Try the cleaning process from Killbucket's tutorial above to see if it fixes the issue first.

[niko_gpsy]

Some build up of carbon on the commutator and initial blue sparks are normal. This is evident in every AEG motor ever produced but a good cleaning as Acidex indicated couldn't hurt as long as the motor isn't damaged.  The use of precut erasers to clean the commutator is a good way and you can use fine grit sandpaper to clean the bruch contacts (or just some rubbing alcohol with Q-tips).  Afterwards make sure the spring is installed correctly.  Try it and let us know what that does for you.

[ElasticShot]

Yea it work's great but I'm not sure if it was as fast as it was out of the box, I'll just have to clean it some more and chrono.

[TheMtn]

superfrog, on 19 March 2012 - 04:40 AM, said:

It's not bad luck, its just man made.

Yep, 100% quality is 97% effective. Humans FSU all the time. Cuz they're human.
To the OP by "fast" you mean ROF and not FPS, correct??

[ElasticShot]

Yeah of course, I'll be chrono-ing for ROF when I get the chance