MacGregorSailors.com

How often should you really change the water pump impeller?
I have a 2007 Suzuki DF70 with about170 hours on it. (three seasons)
My user manual says that you should change it every 200 hours or 12 months.
I am in fresh water

A buddy of mine is in saltwater and has not replaced his in 10 years...

Is this normal recomendation from the manufacturer or a little conservative?

How often DO YOU or CAN YOU typically go between replacements?

(If anyone knows how to make this a polling response question It would be interesting to see the feedback) 1 yr 2 yr 3 yr etc.

I always replace mine every 12 months when it gets serviced. The cost only 30 or so bucks so it isn't a big deal

David It looks like I would need to drop the whole foot of the motor and I guess I just assumed it would be more labor intensive then $30...

parts are usualy around $70.00 plus labour . I'd say if you only paid $30 all they did was inspect it or said they did
I change mine about every 4 yrs but I always carry a spare impella kit & I'm able to do the job myself so it is no big deal for me all depends what kinda water you boat in if dirty brackish water with lots of mud etc I'd change more often
J

Every one hundred hours complete service top and bottom

Yep I was only talking about the part not the labour and I guess the impeller cost may vary depending on model etc. (I have a 30hp) and yes the whole foot needs to be removed to get to it. It is a fairly easy process but I think having an expert looking over your engine regularly is a worthwhile investment. I think my last service, plugs, impeller, grease/oil came in around $270

I replaced mine on my old Merc1 outdrives which is the same as most outboard lower ends. Since I beached that big motorboat on sand I did it every year, or more if I really dug in. It took 2 tools and some grease, about 20 minutes and a $30 part. I carried the spares onboard at all times. My Evinrude gets a service every three years, they gave me the old impeller and it had one damaged vane. From now on I'll be doing it every year because I have never beached my Mac and one of five impeller vanes is more damge than I want to risk. Any impeller that hasn't been changed in ten years with even low hours is toast.

Keep in mind that when replacing worn impellors, especially with broken off / missing vanes, the missing pieces must be found, otherwise they are potentials for clogging water flow and thus could lead to an overheat condition.

(Edit-add: In response to a PM question)

Yes, it is possible that broken impeller pieces can be flushed out on their own and never found. Possible, but not something to count on. It would be better assurance to look for and locate missing pieces in water passages, or confirm that no blockages exist in their abscence. Doing so may be expensive, but losing an engine to an overheat condition would be more so. The best insurance against breaking the impeller is to replace it at regular intervals and not run engine out of the water. Opinions on what is a regular interval varies, hence this discussion.

For boatyards I've worked at, common practice was to replace the impeller at spring commissioning. I've gone every other boating season on my boats with no problems, having inspected it first.

Does anyone on the board have detailed instructions on how to change out the impeller on a 2005 Honda BF50A LRT? Thank-you in advance for your assistance.

Fairwinds,
Jim

I had a 2000 open bow Wellcraft SX that I paid about $23,000 for that I never changed the impeller and used it weekly on Big Bear Lake in California. Then one day in late 2005, my Springer Spaniel was barking to tell me about the white smoke pouring out of the engine - - but the Lake Patrol had already seen it and was racing after me.

End result, $6,000 to replace the engine - - - but then the boat would only be worth $6,000 if I did, so I scrapped a beautiful boat - - -

- - - and bought my 2006 M for $36K and I used it in Marina Del Rey a minimum of 250 times a year for three years (I went sailing every day and played poker at night - - - tough life, but I volunteered). After 3 years my 60 HP ETEC was finally due for service even though I had few hours on it because I always sailed (even tacked out of the marina - - hardly ever motored) and I had never changed the impeller - - -

- - - so I sold the Mac


Rick Less

Captain Jim wrote:Does anyone on the board have detailed instructions on how to change out the impeller on a 2005 Honda BF50A LRT? Thank-you in advance for your assistance.

Fairwinds,
Jim

I could use them too.
Seasonally changing oil is easy but replacing impeller instructions could potentially save an expensive trip to get it serviced.
I do it every other season.

Jim,
I have no details on the Honda but here are a couple of videos I found on youtube:

http://www.youtube.com/watch?v=E-uzQi7IgwU
http://www.youtube.com/watch?v=n68sb7w-3Hw

According to the video it appears to be a 5 minute job

I change my impeller once a year, which is approximately 100 hrs.

An impeller can actually look good when you remove it, but the vanes may have taken a set, and therefore loose their efficiency. If you use your engine in salt water, your lower end removal bolts can freeze, so it is recommended that you change it at least every 2 years, and use an anti seize compound on the bolts. If you use the engine very little, you still need to change you impeller regularly, because it can become brittle, and or loose it's efficiency.

It is one of the least expensive ways you can insure against what could be a catastrophic loss. I replace all the impellers on all my motors, and find it a relatively simple thing to do.

Ric K

Inspect annually. Replace bi-annually.

I will leave it to others to make a movie about it, but here are some notes I just made about impeller change or inspection.

LINK HERE

Matt19020 and Opie,

Thanks for the great info on changing out the water pump on the 50HP Honda! I will give it a go in March when I'm back in N.Y.

Fair winds,

Jim