M5/M6 Impeller Failures

[SteveQ]

Looks like Bakes has both the Globe 626 for Sherwood and the Globe 100J for Johnson

[Sparky450]

1 hour ago, COOP said:

Won't find it online. At least not the one Malibu is having made. Globe makes one, I think it's a 626, but everywhere I've tried to get one is sold out. 

At this point I have not had a problem. But I am really happy I have TWO replacement impellers. Even if they are the old style. 😂😂

[JWBeav]

Just purchased one from Bakes for my Sherwood pump on our 2020...curious if it is still recommended to change every 50 hours?

[gregtay]

I will toss in a comment on the failures.  I do truly think Malibu got screwed by a part manufacture on this and at lot of what happened over the last year was beyond their control (yes.. they could have communicated better... no question.)  My M6 was a relatively early build and we just pulled out the original impeller after 2 seasons and 120ish hours.  It was in perfect condition, could have run it for many more hours (not that I would want to go beyond 2 years.)  At some point the manufacture of the impeller part must have clearly changed something (intentionally or not) and they simply weren't up to spec.  I can't imagine being the engineers at Malibu trying to track down this issue and figure out which impellers are bad and why.  I don't think impellers have any sort of date code or batch code... just a part number.  Really sucks for everyone out there with the bad batch... but I am confident the latest rev (which I now have in my boat) will be just as robust as my original impeller was.

 

Edited April 14, 2021 by gregtay

[Bcott]

Follow up on my post my dealer is putting in the new brass impeller for me this week. So now I just need it to quit snowing!

[oldjeep]

10 minutes ago, Bcott said:

Follow up on my post my dealer is putting in the new brass impeller for me this week. So now I just need it to quit snowing!

Maybe a new brass raw water pump?  I don't think a brass impeller would work very

[Bcott]

The service guy just told me it is a new brass system. I am the guy that gets to pay for repairs since I have zero mechanical abilities.

[NWBU]

My 2021 23 LSV came with the flush kit and one of the sales guys said all their 2021s are coming with that option. Not sure if that’s something the dealer is doing on their end as extra impeller insurance or if it’s part of Malibu’s fix for the issue.

[IXFE]

17 minutes ago, NWBU said:

My 2021 23 LSV came with the flush kit and one of the sales guys said all their 2021s are coming with that option. Not sure if that’s something the dealer is doing on their end as extra impeller insurance or if it’s part of Malibu’s fix for the issue.

The transom flush kit is now standard in 2021.  I got one too.  I've never checked that box.  It's kinda nice they made it standard.  Good one to remember when everybody is whining about how everything is an option.  

[justgary]

4 hours ago, gregtay said:

I will toss in a comment on the failures.  I do truly think Malibu got screwed by a part manufacture on this and at lot of what happened over the last year was beyond their control (yes.. they could have communicated better... no question.)  My M6 was a relatively early build and we just pulled out the original impeller after 2 seasons and 120ish hours.  It was in perfect condition, could have run it for many more hours (not that I would want to go beyond 2 years.)  At some point the manufacture of the impeller part must have clearly changed something (intentionally or not) and they simply weren't up to spec.  I can't imagine being the engineers at Malibu trying to track down this issue and figure out which impellers are bad and why.  I don't think impellers have any sort of date code or batch code... just a part number.  Really sucks for everyone out there with the bad batch... but I am confident the latest rev (which I now have in my boat) will be just as robust as my original impeller was.

 

3 hours ago, IXFE said:

The transom flush kit is now standard in 2021.  I got one too.  I've never checked that box.  It's kinda nice they made it standard.  Good one to remember when everybody is whining about how everything is an option.  

I thought that we established many pages back that this was an engineering mistake.  They raised the water pump to way above the old location, and now it doesn't prime reliably.  Some people's storage/driving habits give them better odds of priming than others, so not everybody had the problem.  The addition of a flush kit should fix it if that is the case.  Just be sure to run it on the hose when you dewinterize....

[gregtay]

Just now, justgary said:

 

I thought that we established many pages back that this was an engineering mistake.  They raised the water pump to way above the old location, and now it doesn't prime reliably.  Some people's storage/driving habits give them better odds of priming than others, so not everybody had the problem.  The addition of a flush kit should fix it if that is the case.  Just be sure to run it on the hose when you dewinterize....

I don't believe it is purely related to the location of the pump.  If that was the case then the solution would be "lower the pump."  Yes, having the pump up high might contribute to the prime cycle being a bit more sensitive, but I believe the original design (including pump location) was fine.  I am sure malibu tested their new motors extensively before launching them.  

 

[ahopkins22LSV]

Reading between the lines a bit, more sounds like a complete supplied part failure that they were just shredding. Early M series engines seem to have no issues. And would also explain why some of us with 2020's had no issues as well, but others had multiple. The rate and occurrence of failures from reading on here and FB just doesn't point to the location to me. A new impeller made by Johnson is the fix for the 2020 boats without the new johnson pump/impeller combo. 

Now it could be the location is a factor or even the main factor and they had to find a solution that didn't involve moving it, but it isn't really feasible to do that so that is why they have the new impellers and new pumps/impellers.

As being an engineer and doing this sort of stuff every day, I'd love to know but I am just happy there is a solution.

[COOP]

There were multiple issues.

Version 1 impellers in the Sherwood pumps had manufacturing issues. (we were told contaminates in the molds, impellers would turn into coffee grounds)

Version 2 impellers in early batches had manufacturing issues (core spinning out, fins breaking off)

It was discovered that many of the Sherwood pumps had an issue on top of the impeller issues.

Pump location may have been a contributing factor which led us to the run dry impellers.

Edited April 15, 2021 by COOP

[JWBeav]

Thanks Coop!  Curious if the run dry impellers will be enough to overcome the Sherwood pump issue?  It seems weird that Malibu is replacing pumps on some boats and only warrantying impellers on others, why not do all the same?...our boat is a later 2020 and has never had a problem for whatever reason.

[gahvey]

3 minutes ago, JWBeav said:

Thanks Coop!  Curious if the run dry impellers will be enough to overcome the Sherwood pump issue?  It seems weird that Malibu is replacing pumps on some boats and only warrantying impellers on others, why not do all the same?...our boat is a later 2020 and has never had a problem for whatever reason.

Like most recalls, my guess is that Malibu knows the boats that have the specific Sherwood pump issue.  Guessing that Sherwood knew the SN's of the pumps that were bad and that is recorded somewhere in the Malibu archives that link to the boats that have them.

[COOP]

24 minutes ago, gahvey said:

Like most recalls, my guess is that Malibu knows the boats that have the specific Sherwood pump issue.  Guessing that Sherwood knew the SN's of the pumps that were bad and that is recorded somewhere in the Malibu archives that link to the boats that have them.

Correct. Not every Sherwood pump is bad. 

[JWBeav]

any idea when the bad pumps were installed in boats?

[Slurpee]

The service bulletin I was shown said that after removal of the old impeller check to see if the brass fitting inside the housing fit flush to the surface.  Those brass fingers of the comb taper down and give a smooth ramp from the cylinder.  If those fingers weren't making good contact or misshapen then replace the pump.  Otherwise go with the new impeller.  Also make sure the sea strainer was installed with the flow in the right direction.  I pulled my 2019 impeller after 70 hours and it looked just fine.  The only wear on the fins was on the bits of the fin that passed over the voids between combs as opposed the combs themselves.  Those parts of the rubber looked perfect.  But then again I don't trailer, it sits on a lift.  

 

[Idamon]

On 3/24/2021 at 6:05 PM, Chrismoe said:

Hi COOP,

I just bought a 2021 25 LSV with an LT4. Can you please confirm for me (no pressure) that the impeller issue is not impacting the LT4's?

Many thanks COOP,

Chris

I can confirm that my 2021 M240 with an LT4 came with the defective Johnson impeller which fell apart at 45 hrs. Dealer says it is on a recall list.

Edited June 8, 2021 by Idamon

[jcon44]

I just passed 20 hours on my new Bakes impellor. That's about when the original blew up. Fingers crossed...

[23LSVOwner]

10 hours ago, Idamon said:

I can confirm that my 2021 M240 with an LT4 came with the defective Johnson impeller which fell apart at 45 hrs. Dealer says it is on a recall list.

 

If it was on the Service bulletin list it did not come with a Johnson pump or impeller.

 

If it had it would not have been on that list.

[ThrashMetash]

Need some help with impeller install.
So, my impeller (Axis 2020 T22) failed on the lake at around 35-40 hours.  I had two spare impellers on board just in case.

I figured it would be fairly simple to just remove the old impeller and insert the new one.  I took off the 4 5/16" bolts and the back place slid off easily.  The bad impeller came out with some bent needle nose pliers.  I then spent about an hour trying to get the new impeller to fit in there.  I lined up the keyhole as best I could but it would not go in.  I could not get the old one in either.  Is there a trick to get the keyhole lined up?  It seems the impeller hits the key even if it is lined up properly such that it won't go on.  Anyway, it was getting dark so we flagged someone down to give us a tow.  Its still sitting in my garge with no impeller and letting everything cool down doesn't seem to have helped.

I haven't seen anything that would suggest it should be that difficult to install.  Anyone have any advice?

[dwc032]

40 minutes ago, ThrashMetash said:

Need some help with impeller install.
So, my impeller (Axis 2020 T22) failed on the lake at around 35-40 hours.  I had two spare impellers on board just in case.

I figured it would be fairly simple to just remove the old impeller and insert the new one.  I took off the 4 5/16" bolts and the back place slid off easily.  The bad impeller came out with some bent needle nose pliers.  I then spent about an hour trying to get the new impeller to fit in there.  I lined up the keyhole as best I could but it would not go in.  I could not get the old one in either.  Is there a trick to get the keyhole lined up?  It seems the impeller hits the key even if it is lined up properly such that it won't go on.  Anyway, it was getting dark so we flagged someone down to give us a tow.  Its still sitting in my garge with no impeller and letting everything cool down doesn't seem to have helped.

I haven't seen anything that would suggest it should be that difficult to install.  Anyone have any advice?

Hmm, never had those problems.  Do you possibly have the non updated impeller??  Going into the updated impeller pump?  

[hethj7]

Did you use a little bit of soap or spit to lube it?  I got it close to the key and then was able to “squeeze” it in while standing in the swing platform. 

[ThrashMetash]

The strange thing is that I can't get the old impeller on either.  It is pretty much missing all the ribs so it should in theory go on with ease.  Its as if the key is too big and won't fit in the keyway but I know it came out of there.