Impeller change at 80 hours...

[sheral]

Just a 'fwiw,' to anyone who may think it's not worth checking the impeller more often than every 100 or 200 hours...

We had our 50 hour Volvo Penta service a while back and the tech just looked over the side to see how much water was shooting out the exhaust to determine if everything was good with the impeller/pump - which it probably was. I just mention this because I wonder if at a 50 hour service check if the tech really shouldn't physically check the impeller?

I can guarantee that the impeller has been spitting out water each and every time we have used the boat, as I put a new one in at three hours (long story - and have been super paranoid ever since, so check it incessantly). The boat has not been run dry at all since the new impeller was installed.

Anyways, today while working through my winterizing checklist and installing the new 'Speedseal impeller kit' I pulled out the impeller and inspected it. Disappointingly, it had very small cracks at the end sides of two vanes. Scratching my head on this one as the impeller was well lubed up when installed and the system was primed to ensure it got water right away. Maybe the Speedseal kit will help the impeller last longer than 80 hours before showing signs of wear.

 

[baz]

Are you boating in water that has a lot of sand debris suspended in the water, or running in shallow waters with the sea bed being sandy and the like. This can cause a lot more abrasion to the impeller material.

A partially blocked raw water pickup grate could have cause a brief period for the impeller to run dry... Jelly fish come to mind. :roll:

Was the impeller the correct part ? If too large the impeller vanes will bend more than they should and lead to premature failure.

Run your finger tips around the inside of the impeller pump housing to feel any nasty grooving, unevenness or simply inspect the surface with a flashlight. The surface should be very smooth.

Where did you order the Speedseal impeller kit from ? Was it the new Speedseal Life unit ?

It really amazes me the huge deviations between the time impeller failures occur that boaters report. It all seems to me as being unlucky, hit-and-miss, faulty installation, running dry for too long, bad maintenance, simply aging and so on.

 

[sheral]

Yes, lots of sand here, but I never beach the boat etc. Ordered the impeller through Volvo and it is apparently the correct part number - I think it was 22222936. We got the speed seal life kit through the 1-800 USA number and it was shipped from the UK.

 

[knotflying]

Try one of those run dry impellers and see what happens. They are a bit more expensive, but supposedly can take the abuse longer.

 

[sheral]

Can anyone confirm that the Johnson Pumps 09-1026B-1 impeller is the same as the V-P 22222936 impeller?

 

[sheral]

Can anyone confirm that the Johnson Pumps 09-1026B-1 impeller is the same as the V-P 22222936 impeller?

I have now confirmed that the a/n Johnson number is a direct replacement for the a/n VP impeller. No doubt Johnson makes them for VP (once you see them you will see why 🙂 They were about $12 each versus $40 ... FWIW.

 

[baz]

...snip...

Anyways, today while working through my winterizing checklist and installing the new 'Speedseal impeller kit' I pulled out the impeller and inspected it. Disappointingly, it had very small cracks at the end sides of two vanes. Scratching my head on this one as the impeller was well lubed up when installed and the system was primed to ensure it got water right away. Maybe the Speedseal kit will help the impeller last longer than 80 hours before showing signs of wear.

Ref: "...it had very small cracks at the end sides of two vanes."

Can you post a picture of the impeller cracks ? Are the cracks at the base of the vane or at their tips ?

 

[sheral]

The cracks were at the base of the vanes. You would have to manipulate the vanes to actually see the cracks. Hope that makes sense. That impeller is no longer in this world...