Dewalt demo hammer, when switched on the motor speed surges up and down constantly. What is wrong?

The high-speed motor of DEWALT DCK299P2 Hammerdrill & Impact Driver Combo Kit gives you great power and precision. You can switch through three different speeding options from 0 to 2000 RPM. It provides you the access to all metal transmission. You can increase the speed with the impact driver to a maximum of 3600 RPM.

Check the brushes and commutator for bad contacts due to dirt, etc.
Ditto for motor bearings and associated mechanism.

If cleaning all has no results then the motor is bad.

It is very common the extra grease that is on the machine to become oil and came out from the machine. In case you think that you lost more 500 ml of oil then it is is a problem. 100 ml is not a problem at all. Use your machine to demolish what you want to.

Acceleration is defined as a change in speed, either a negative acceleration (slowing down) or a positive acceleration (speeding up). If you have constant speed, you are not accelerating.---------------------------------------------------------------------------------------
Multi-Di@g Access

The gasket your looking for is part# 487224-00 SEAL which lists for $3.65. The gearcase should use LUBCON GLK 249 grease spread evenly across the gears. Be careful with the amount you apply, too little grease will not properly lubricate and too much will create additional friction cause the to motor to work harder, thus reducing its effectiveness and longevity. ONLY THIS GREASE SHOULD BE USED ON THE INTERNAL COMPONETS OF THIS TOOL. Note that the bit grease is different than the gearcase grease and SHOULD NOT be used on any internal components.

5g on connecting rod and piston - inside and out

39g in gearcase evenly coating all parts

39g in crankcase

If the battery is OK then the problem will be in the variable speed trigger switch.

On most sds drills the movement of the beat piece inside the piston cause then to vibrate, even at slow speed, this is normal, the most speed the louder the noise and vibration., note: is not a grinding noise, it should be a smooth nocking constant sound, as so the vibration.

skil is owned by bosch :)
so i would have a look at the bosch site as this may well be a rebadged bosch demo hammer ( skil dont do them anymore )

http://www.skilmasters.com/service_onderdelenservice.php

hope this helps :)
if it does please vote

Yes there is I looked and the model number posted is a demolition hammer, so you might want to recheck before checking, but go to Dewaltservicenet.com and in the middle of the page it will ask you for parts or below that manual, go to manual and type in your model number and you will get an explosion and current pricing for this tool. Let me know if I can help I work on their demolition hammer on occasion. Good luck

PGD 97-0603-625 (for 5/8" rod)
PGD 97-0603-750 (for 3/4" rod)

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