MP40 repair help

brad · 12/09/2019, 03:43 PM

I bought an old MP40 from a friend who took down his tank years ago. It sounded like a lawn mower, and I found a thread on here to change the bearings, which I did.

I used:
uxcell 698-2RS Deep Groove
and
XiKe 607ZZ Precision Bearings 7x19x6mm

Before, running just the dry side alone was very loud. Now the dry side alone is almost silent, but still almost as loud as before when I run it with the wet side.

Has anyone tried any grease or lubricant inside the motor? I suspect the shaft/magnet inside the motor is making contact with the plastic. If this is the case, lubricant should quiet things significantly, and if it isn't, it shouldn't hurt anything.

Is my choice of bearings a problem?

Is it possible I have a different problem with the wet side and my dry side is fine?

Is it possible I put it together wrong, even though the dry side seems quiet alone?

This is a "generation 2" pre-QD MP40

ca1ore · 12/10/2019, 07:19 PM

If the wetside is also pre QD then it’s well past tge replacement point. They chatter as they age.

12/09/2019, 03:43 PM	#1
brad Registered Member Join Date: Feb 2001 Location: Hudson, OH Posts: 1,347	MP40 repair help I bought an old MP40 from a friend who took down his tank years ago. It sounded like a lawn mower, and I found a thread on here to change the bearings, which I did. I used: uxcell 698-2RS Deep Groove and XiKe 607ZZ Precision Bearings 7x19x6mm Before, running just the dry side alone was very loud. Now the dry side alone is almost silent, but still almost as loud as before when I run it with the wet side. Has anyone tried any grease or lubricant inside the motor? I suspect the shaft/magnet inside the motor is making contact with the plastic. If this is the case, lubricant should quiet things significantly, and if it isn't, it shouldn't hurt anything. Is my choice of bearings a problem? Is it possible I have a different problem with the wet side and my dry side is fine? Is it possible I put it together wrong, even though the dry side seems quiet alone? This is a "generation 2" pre-QD MP40

12/10/2019, 07:19 PM	#2
ca1ore Grizzled & Cynical Join Date: Apr 2006 Location: Stamford, CT Posts: 17,319	If the wetside is also pre QD then it’s well past tge replacement point. They chatter as they age. __________________ Simon Got back into the hobby ..... planned to keep it simple ..... yeah, right ..... clearly I need a new plan! Pet peeve: anemones host clowns; clowns do not host anemones! Current Tank Info: 450 Reef; 120 refugium; 60 Frag Tank, 30 Introduction tank; multiple QTs