Water pump fly wheel came off today on the water

[JBell]

So I had the fly wheel come off on the water today and obviously the serpentine belt came off as well. When trying to put the flywheel back on I did not see any bolt, clip, keyway, set screw or anything that would secure the flywheel on the shaft. Just tapped the flywheel back on to seat it then put the belt back on. 
 

Anybody have any info on this? It seems like the way I have it set it will eventually work itself off again.  This is on a 2020 23 LSV M6DI.

[ahopkins22LSV]

I’m lost. The main fly wheel came off? Did you take pictures? I’m going to go out on a limb and say it should not just tap back in place. I’d be very inclined to take the boat straight to the dealer for a full analysis on the engine to make sure nothing else is wrong. 

[JBell]

Sorry I’m using the incorrect terminology. It is the pully on the fresh water pump. Where your serpantine belt would wrap around.Back side of where you would pull out and replace the impeller. 

[Eagleboy99]

Get thee to your dealer as already mentioned.  A loos water pump pully could create a maelstrom (pun intended).

[ahopkins22LSV]

Are the bolts and nuts to the bracket as shown in this picture still there? This is of my engine. I still am lost on how it slid off then just back on. I feel like there is normally a center not on the shaft of pulleys/fly wheels. Or a plate with 3-4 nuts on the face of the pulley/fly wheel. 

[JBell]

Here is what mine looks like. When the pully was off there was a smooth shaft sticking out. The inside and outside of the pully wheel are smooth sided. It looks like there is a groove on the actual pump where the pully seats against it but no matching groove on the inside of the pully wheel. When you seat the pully wheel on the shaft it is flush to the backside of the wheel as you can see in the picture. No threads for a bolt, no hole for a pin or a groove for a clamp.

I am baffled too about it because it doesn’t seem like anything is sheered or broken but when I seat the wheel it doesn’t seem like there is anyway to secure it out than the tension from the belt. Makes me think it would just eventually work itself off again.

Edited August 9, 2020 by JBell

[ahopkins22LSV]

Personally, I’d you are a do it yourselfer, I’d try to take those three bolts off, loosen then idler pulley and take the water pump pulley off again to see if you can see any damage. 

[JBell]

I checked it yesterday before I put it back on. No damage to the belt or pully. Was more confused that I saw no dicernable way to secure the pully wheel in place to the shaft 

[JBell]

You can see the backside of those 3 bolts in my third picture. They only serve to attach that that large washer that seats agains the pump housing. They do not attach to the housing itself. 

[UWSkier]

5 hours ago, JBell said:

Here is what mine looks like. When the pully was off there was a smooth shaft sticking out. The inside and outside of the pully wheel are smooth sided. It looks like there is a groove on the actual pump where the pully seats against it but no matching groove on the inside of the pully wheel. When you seat the pully wheel on the shaft it is flush to the backside of the wheel as you can see in the picture. No threads for a bolt, no hole for a pin or a groove for a clamp.

I am baffled too about it because it doesn’t seem like anything is sheered or broken but when I seat the wheel it doesn’t seem like there is anyway to secure it out than the tension from the belt. Makes me think it would just eventually work itself off again.

Believe there is a piece missing. Supposed to be a support added to that pulley as a TSB iirc. 

[justgary]

If the shaft has a flat, it probably has a set screw.  Remove the pulley from the hub and tighten the set screw on the hub until it seats against the shaft.  Then reinstall the pulley with the three bolts.

[JBell]

15 hours ago, justgary said:

If the shaft has a flat, it probably has a set screw.  Remove the pulley from the hub and tighten the set screw on the hub until it seats against the shaft.  Then reinstall the pulley with the three bolts.

Shaft does not have a flat. It is completely cylindrical. ALso, those three bolts only connect the smaller washer piece to the inside of the pully. You can see that in the second picture.

 

Does any one have a M5 or M6 engine that could take a picture of the same angle of my second picture? That way I can see if anything is different.

[gregtay]

20 hours ago, UWSkier said:

Believe there is a piece missing. Supposed to be a support added to that pulley as a TSB iirc. 

That is only for the original style 4 bolt pulley. The one is the photo is not the one that has the TSB.

[23LSVOwner]

2 hours ago, gregtay said:

That is only for the original style 4 bolt pulley. The one is the photo is not the one that has the TSB.

And it is this pulley, IIRC, and it looks like it has it:

 

[gregtay]

1 minute ago, 23LSVOwner said:

And it is this pulley, IIRC, and it looks like it has it:

 

opps.. correct.   Now I am confused as to which pulley does what.    Raw water vs. closed cooling pumps?

[23LSVOwner]

2 minutes ago, gregtay said:

opps.. correct.   Now I am confused as to which pulley does what.    Raw water vs. closed cooling pumps?

The top one is the raw water pump.

[JBell]

Just talked to the dealer and apparently the silver flange that has the 3 bolts is factory "pressed" on to the tapered post in the raw water pump. Was told the solution is to replace the entire pump housing.

[jmack]

1 hour ago, JBell said:

Just talked to the dealer and apparently the silver flange that has the 3 bolts is factory "pressed" on to the tapered post in the raw water pump. Was told the solution is to replace the entire pump housing.

If covered under warranty and they can get to it quickly, then great. If not, I'd look to try to drill and tap the center hub for a set screw.

[23LSVOwner]

Ask the dealer to get one in there ahead of time and when you take it in it's a quick job.

[justgary]

18 hours ago, JBell said:

Just talked to the dealer and apparently the silver flange that has the 3 bolts is factory "pressed" on to the tapered post in the raw water pump. Was told the solution is to replace the entire pump housing.

Is the post really tapered?  Pressing something onto a taper makes no sense.  The shaft is either straight with a pressed hub, or tapered with a nut to hold the tension.  My vote is a set screw like @jmack said.

1 hour ago, 23LSVOwner said:

Ask the dealer to get one in there ahead of time and when you take it in it's a quick job.

Or even have them get the item in stock, then you swing by and change it in the parking lot and have their mechanic inspect and sign off on your work.  If they are truly swamped, they might just go for that.

Looking at your top-down photo, I predict that this is going to be a problem for them until they fix it with a set screw or something.  The shaft is forward of the belt, which means that the belt under tension tries to rock the hub on the shaft.  Even a pressed hub will eventually walk off of the shaft as it heats and cools while rotating with the constant torque on the side.

[oldjeep]

17 hours ago, jmack said:

If covered under warranty and they can get to it quickly, then great. If not, I'd look to try to drill and tap the center hub for a set screw.

I'd spend the $100 on a new one before I messed around trying to get a set screw in and hope that it held against a hardened shaft.

Should be warranty on a 2020 though

[oldjeep]

3 minutes ago, justgary said:

Looking at your top-down photo, I predict that this is going to be a problem for them until they fix it with a set screw or something.  The shaft is forward of the belt, which means that the belt under tension tries to rock the hub on the shaft.  Even a pressed hub will eventually walk off of the shaft as it heats and cools while rotating with the constant torque on the side.

Doesn't look any different than every smallblock GM water pump ever made.

Edited August 11, 2020 by oldjeep

[justgary]

7 minutes ago, oldjeep said:

Doesn't look any different than every smallblock GM water pump ever made.

Fair enough.  I doubt the shaft is so hard that he couldn't file a flat on it.  A set screw is probably harder anyway, and will cut the shaft enough even without a flat.  It shouldn't take much.

[JBell]

6 hours ago, justgary said:

Is the post really tapered?  Pressing something onto a taper makes no sense.  The shaft is either straight with a pressed hub, or tapered with a nut to hold the tension.  My vote is a set screw like @jmack said.

Or even have them get the item in stock, then you swing by and change it in the parking lot and have their mechanic inspect and sign off on your work.  If they are truly swamped, they might just go for that.

Looking at your top-down photo, I predict that this is going to be a problem for them until they fix it with a set screw or something.  The shaft is forward of the belt, which means that the belt under tension tries to rock the hub on the shaft.  Even a pressed hub will eventually walk off of the shaft as it heats and cools while rotating with the constant torque on the side.

That's what they said at the dealer. (To be honest i don't fully trust them on this. they sent me back and forth 3 times between parts and service to figure it out until I told them to go ask a mechanic or let me ask them.) Maybe it is not actually a tapered post but a strait post that is pressed onto. 

I am selling the boat and am supposed to hand it over tomorrow so this was bad timing for me. I ended up ordering a pump and paying for it out of pocket and got it overnighted. It was going to take a month if I went through the warranty process. Only thing I am worried about now is that Malibu will not honor a warranty claim on this in the future if there is problems because I did the work myself.

[oldjeep]

3 hours ago, JBell said:

That's what they said at the dealer. (To be honest i don't fully trust them on this. they sent me back and forth 3 times between parts and service to figure it out until I told them to go ask a mechanic or let me ask them.) Maybe it is not actually a tapered post but a strait post that is pressed onto. 

I am selling the boat and am supposed to hand it over tomorrow so this was bad timing for me. I ended up ordering a pump and paying for it out of pocket and got it overnighted. It was going to take a month if I went through the warranty process. Only thing I am worried about now is that Malibu will not honor a warranty claim on this in the future if there is problems because I did the work myself.

They can't do that.