Dremel 4000 Troubleshooting

changed the fusible, and the rotation is not smooth and make noise again and the fusible gets burned again. the Dremel is brand new and clean. worked fine for some hours.

My dremel4000 was working great but I tried this with a 15mm ply and the 561 bit to make a hole. I kept the dremel running for a long time and it got some goose bumps kind of bubble on the rubber side and stopped working. What would be the problem

The electrical assembly does not necessarily need replacing if the tool does not start when switching it on. The switch design is not very robust. The blue plastic on/off button operates a little microswitch just under the variable speed adjuster. If the blue plastic is not pressing firmly on the microswitch then it can fail to turn on. I just took mine apart and refitted everything and it worked. If it fails again then I will glue a little packing piece on the blue plastic to ensure that everything presses firmly together. That ought to fix it.

Ive been disappointed with my 4000 series Dremel. I returned one and then its replacement stopped working. Like David, I also narrowed the problem down to the micro switch not closing properly from the blue slider distorting/wearing down.. It may seem this switch is wimpy for the tool but since the tool is FET driven there is very little current flowing through the switch.

I bought a Dremel 4000 on January 28th of this year (2017), just 21 days ago, but I used it for the first time up to a week after purchasing it to remove rust from various accessories of my Dremel 395, from that very first moment I noticed an excessive heating in the Dremel 4000, at the point where the accessories are installed, I estimate that the temperature would be between 54 and 60 degrees Celsius, excessively hot. After checking details such as not obstructing the ventilation holes and checking the free rotation of the rotor without noises or obstructions, and see that everything was fine, I took the Dremel 4000 to the service center of my town where after an "inspection" Of the tool, the qualified technician stated that he had not found anything abnormal in the tool. I asked to have it run in front of me, and after only 5 minutes and without work load, the tool had an excessive temperature that was perceived through the plastic armor and at the tip, the temperature was too high to touch.

In spite of this demonstration of anomaly the authorized service personnel justified with many reasons, some nonsense, the high temperature of the tool, explaining that as the armature did not touch with the field and the bearings did not make any noise, the tool could not be wrong, meaning that they could not validate the warranty or repair the tool.

I retired to my home somewhat disappointed and began to look for information related to this problem of overheating of the Dremel 4000 in the web. In addition to this site, I found many others where this problem with the Dremel 4000 was discussed (including Youtube).

As I do not know if Dremel will validate the warranty and will repair the tool I decided to review it myself, and here is what I found:

The tool is not misaligned, that is, the armature does not stick in any way with the field, as because of friction, high temperature could be generated. The design of the plastic body is not bad nor comes poorly molded factory which could cause an increase in temperature due to poor ventilation. Finally the brushes and rotor were clean, as intermittent contact between brush and rotor can cause an increase in the temperature in the system.

As all of these factors were correct there was only one factor that could cause high temperature in the tool and these were the bearings. So I carefully extracted the armature assembly and bearings and made a simple test: I took the armature through the bearing of one end and letting it hang by holding it only from the bearing then I turned it,

when I took the armature by the bearing that is on the side the brushe´s side, the armature spun free as for 4-5 seconds and stopped gently, but when I took the armor by the bearing that is next to the fan and I turned it, this turned only 2 or 3 TURNS and stopped abruptly. There is no doubt, the damage is in the bearing that is next to the fan.

So I proceeded to remove the seals from the bearing to see what the problem might be, when I removed the seals I saw the problem, what should be the lubricating grease was completely solidified as if it had become solid plastic, this did not obstruct the turning Of the bearing but yes it stopped the free rotation of the steel balls and obviously causes a severe friction which causes excessive temperature in the tool.

I have photos I took of the armor of the Dremel 4000, I do not know if I can share them here, but whoever wants to see them can send me a message to me.

I have photos I took of the armor of the Dremel 4000, I do not know if I can share them here, but whoever wants to see them can send me a message to me.

I have photos I took of the armor of the Dremel 4000, I do not know if I can share them here, but whoever wants to see them can send me a message to me.

I have photos I took of the armor of the Dremel 4000, I do not know if I can share them here, but whoever wants to see them can send me a message to me.

I have photos I took of the armor of the Dremel 4000, I do not know if I can share them here, but whoever wants to see them can send me a message to me.

I have been through 4 dremels, 3 4000 models and 1 3000 model. All off them would short out , no power, hand jigsaw no pover, 2 hand wands just spin and no power either. What the heck!!! I want someone to answer, I want a sales rep to replace all your broken equipment. This is ridiculous, I have been a Dremel tool lover since 96, as an manicurist I depended on its reliability, and I still do.

i just got mine last week, i think all is well, after some tests, started getting additional accessories for my Dremel 4000, twas manufactured November 2016, i noticed the spot where you access your carbon brush ? you cant screw it out ! and i got me some carbon brushes ordered already ...... my Dremel 4000 with manufacturing date November 2016 with a "611" number underneath the date, you cannot access carbon brushes from the out side.....

i happened to see in youtube a guy disassembling his Dremel 4000 and you can unscrew carbon brush hatch from the outside, not having to open it up???????

Check the brush holder #26100009854 with a multimeter… If there is no continuity, replace.

My Dremel was either intermittent or died when under any load. An air blow out/clean made no difference. Brushes were basically new. I disassembled the unit and noticed a tiny piece of metal fell out. This turned out to be part of one of four slide contacts between the circuit board/switch assembly and the external main coil assembly. These 2 main parts connect together via 4 pins and 4 sliders. Two had broken so the contacts were loose at best but mostly non-existent. I was able to give it a McGyver fix with thin slithers of metal that help to maintain the contact. How did this happen? I do not know. My Dremel is out of warranty but has not had that much use. Well ,fixed and useful for now.

Hope that description helps someone else fix their Dremel.

My Dremel will only work on high speed what can it be

Hi my dremel starts squicking sounds after 30second running and then starts slowing and burn off. ,i off it and after some minutes tried to power on, It run but does not revolve the shaft ! What could it be?

My Dremel will switch on but will not turn off if you turn off the power it does not start until you press the button to turn it on. What would be the problem?

My collet nut is stuck and i can't get it off any suggestions? I have already tried heat and banging on it .

my new dremel seems to rotate well but you can hear it is not constant, and tends to have very short bumbps of lower speed in between..like

vooooooooo ‘vooooooooooovo’voooooooo’voooooooo’vovooooo

!! is the motor having problems rotating uninterruptedly?

Dremel working fine…started a mild rattling noise the slowed to stop won't restart

Any one got collet dremel 480 falling into pieces very frequently when using cutting tools? Any tips on how to limit this?

I don't know but it looks like my fan is rubbing against the plastic on my Dremel.4000

my Dremel 4000 stopped working. the shaft span freely so took apart to check it.

the primary and secondary coil all seem ok so assumed it was the speed control.

have changed this but still not working.

as the field (coils) seems fine, would i be correct to guess its the armature?if so, how can i test this

I purchased a brand new dremmel and it worked for 7 minutes. Withou making any unusual noise or even binding it turned off and will not restart. I am not a novice at using a rotary tool. The dremmel is an overpriced piece of trash don’t waste your money.

My Drexel multi tool will work only with the head point upward. If I turn it sideways or upside down it stops

Dremel 4000 pulsing continuously.

Hi,

I inadvertently plugged in my Drexel 395 multi speed which is rated for 120v ( it was bought in the USA ) into a 240v outlet.

Is it repairable and if so which parts need to be replaced?

I've hardly used my 4000 and the switch has stiffened so much I can barely turn it on or off. What is the solution?