Mp40 rattles and falls off at startup

[kimros1986]

Hello!
I've gotten an mp40 wqd second hand that I installed the other week. I had a real problem with the start. The dry or the wetside started rattling like crazy, which led to the wetside sliding off (down). I had to restart/realign for like three times before it stuck (and being really nice and quiet).
Just now we had two power failures due to a bad toaster. The second time the power came back on the same issue happened with the mp40, started rattling and then wetside slide off. Had to restart (unplug) /realign two times before I got it stuck.
This means that every time I kill the power to my mp40 I run the risk of it not starting up again without me getting my hands wet to realign them.

Anyone knows why this might be? It couldn't be misaligned this time since power killed it at the same position as it started again.

 

[bevo5]

I'm no expert - but I have had trouble with the wet side staying on when the glass is too thick.

 

[Biddence]

Hello!
I've gotten an mp40 wqd second hand that I installed the other week. I had a real problem with the start. The dry or the wetside started rattling like crazy, which led to the wetside sliding off (down). I had to restart/realign for like three times before it stuck (and being really nice and quiet).
Just now we had two power failures due to a bad toaster. The second time the power came back on the same issue happened with the mp40, started rattling and then wetside slide off. Had to restart (unplug) /realign two times before I got it stuck.
This means that every time I kill the power to my mp40 I run the risk of it not starting up again without me getting my hands wet to realign them.

Anyone knows why this might be? It couldn't be misaligned this time since power killed it at the same position as it started again.

I had the same problem, one was a bad dry side that needed to be replaced on a basically new pump. The other time it was just misaligned.. looking directly at it from the sides my tank.. looking through the glass and water will give it the illusion that it’s lined up when it’s really not

 

[kimros1986]

I'm no expert - but I have had trouble with the wet side staying on when the glass is too thick.

Well, as soon as it's aligned and up and running it doesn't fall off. Neither when coming back from feed mode.
It's only when power has been off and it starts back up again. Rattling like a drill..
I have used the guide for the spacers and have the thin rubber for my 12 mm glass

 

[Billldg]

I would take the wet side apart and check the ceramic shaft.

 

[kimros1986]

I had the same problem, one was a bad dry side that needed to be replaced on a basically new pump. The other time it was just misaligned.. looking directly at it from the sides my tank.. looking through the glass and water will give it the illusion that it’s lined up when it’s really not

Yeah it's difficult to just align by sight. But this time I had my wife plug in the power while I held the wet side, it started rattling like crazy, meanwhile I tried sliding it around trying to make it aligned. Didn't work, had to turn it off, then back on again, rattled quickly at start but then stuck. Now quiet drift.

It might be a defect dry side?

 

[kimros1986]

I would take the wet side apart and check the ceramic shaft.

I'm coming to the same conclusion. Do you know where there might be a guide for doing this? Don't know what to look for on the ceramic shaft when it's opened.
Cheers.

 

[kimros1986]

I would take the wet side apart and check the ceramic shaft.

Sorry I have checked the wet side BTW, can't see any damage. Although, two of the plastic strings on the cage is off the center ring.

 

[Saltinmyblood]

Hello!
I've gotten an mp40 wqd second hand that I installed the other week. I had a real problem with the start. The dry or the wetside started rattling like crazy, which led to the wetside sliding off (down). I had to restart/realign for like three times before it stuck (and being really nice and quiet).
Just now we had two power failures due to a bad toaster. The second time the power came back on the same issue happened with the mp40, started rattling and then wetside slide off. Had to restart (unplug) /realign two times before I got it stuck.
This means that every time I kill the power to my mp40 I run the risk of it not starting up again without me getting my hands wet to realign them.

Anyone knows why this might be? It couldn't be misaligned this time since power killed it at the same position as it started again.

There is a glass thickness gage, did you adjust to proper glass thickness?

 

[kimros1986]

There is a glass thickness gage, did you adjust to proper glass thickness?

Yeah I have the rubber patch, glass is 12 mm. I had the same problem with the thin spacer on. Thought that was the problem first

 

[Saltinmyblood]

Yeah I have the rubber patch, glass is 12 mm. I had the same problem with the thin spacer on. Thought that was the problem first

You don't see anything where the cord comes out of the dry side not the rubber that you stick to the glass it's on the dry side

 

[kimros1986]

You don't see anything where the cord comes out of the dry side not the rubber that you stick to the glass it's on the dry side

No nothing

 

[Saltinmyblood]

No nothing

Okay so you have the three rubber spacers? And you're using the proper spacer so the only other thing it could be is this not lined up properly so when it's running and you adjust it in the tank until it stops making noise it should be set you shouldn't have any issues. Unless of course something's way out of balance on the west side

 

[Reef - Tripp]

You could do a factory reset, the vortech for safety when the dry side of the wet is detached it turns off and because the porality of the magnets changes, the other option as already mentioned is to check the magnet and the axis of the wet side, like this You can start the engine yourself and hear the dry side without the wet side

 

[Biddence]

Yeah it's difficult to just align by sight. But this time I had my wife plug in the power while I held the wet side, it started rattling like crazy, meanwhile I tried sliding it around trying to make it aligned. Didn't work, had to turn it off, then back on again, rattled quickly at start but then stuck. Now quiet drift.

It might be a defect dry side?

it would be pretty obvious, the dry side would make some serious noise.. but make sure the pump is off and you are perfectly aligned on both sides before you turn back on

 

[Saltinmyblood]

Okay so you have the three rubber spacers? And you're using the proper spacer so the only other thing it could be is this not lined up properly so when it's running and you adjust it in the tank until it stops making noise it should be set you shouldn't have any issues. Unless of course something's way out of balance on the west side

No nothing

I would absolutely make sure the Wet Side was on and holding tight before turning it on

 

[Billldg]

Sorry I have checked the wet side BTW, can't see any damage. Although, two of the plastic strings on the cage is off the center ring.

You will need to take it apart and check the ceramic on the shaft

 

[Billldg]

This is a new MP40 wet side, but, disassembled

The blue circle is the ceramic shaft, and in the red is were it comes apart, you will see the steel shaft and not ceramic.

In order to tear it down, in the below picture, you will see a blue arrow and a red arrow. The blue arrow is the separation between the guard and the propeller housing. Grip the base with one hand and the guard with the other hand. As the red arrow shows, turn the guard clockwise and the base counter clockwise to remove the guard. From there the propeller just pulls off by popping the 3 tabs. Be gentle with the tabs as they are plastic and will break.

 

[SaltyT]

^^^^ yes, this is a great pictorial @Billldg . After you do this, clean and reassemble your MP40 will probably work like new. Works for me every time I have this same issue.

 

[kimros1986]

This is a new MP40 wet side, but, disassembled

The blue circle is the ceramic shaft, and in the red is were it comes apart, you will see the steel shaft and not ceramic.

In order to tear it down, in the below picture, you will see a blue arrow and a red arrow. The blue arrow is the separation between the guard and the propeller housing. Grip the base with one hand and the guard with the other hand. As the red arrow shows, turn the guard clockwise and the base counter clockwise to remove the guard. From there the propeller just pulls off by popping the 3 tabs. Be gentle with the tabs as they are plastic and will break.

Thanks for a great pic tutorial! This is what I already had done and I could see no damage or debris anywhere.