What am I doing wrong with my Impellers?

[mesquito_creek]

I am reading some other threads were people are talking about not replacing their water impellers over multiple seasons or for many years. I have owned 3 VPs, 2 Merc OB, and Mercruisers Bravo/Alphas. I have never reliably got more than a season out of an impeller. Maybe its because they sit in AZ out of the water?... But last year one of my Alpha impellers went bad at about 50 hours/8 months and it sits in a slip/water full time. I use only Quicksilver OEM parts. I grease them up on installation for the first dry firing.

 

[fishing fool]

It also depends how much you use the boat. To me more use it will last longer without drying out. Also where you boat, is the water dirty? Do you beach your boat and drag the drive in the sand? Sand dirt will eat up the impeller real fast.

When I install a new one I use dish soap not grease. Do it every other year

 

[Ricks raft]

merc outboards, volvo penta(so easy!), mercruiser, i usually change every other season unless it gets run dry or sucked up crap. its amazing how fast running dry will destroy it.
i have found running much over idle on the hose will a destroy it quickly. usually 30-50 hrs per year.

 

[Runs2rch]

It also depends how much you use the boat. To me more use it will last longer without drying out. Also where you boat, is the water dirty? Do you beach your boat and drag the drive in the sand? Sand dirt will eat up the impeller real fast.

When I install a new one I use dish soap not grease. Do it every other year

Sand is the main impeller killer. I use Vasaline when I assemble them.

 

[dribble]

I got four seasons out of my last impeller and when I took it out it still looked good. Make sure the housing isn't scored. I also use dish soap and I never start the boat without water, not even for a second.

 

[COCA COLA COWBOY]

The retirees in Havasu use their boats all year round and can get away with that. If you're just using it and putting it away for a month in a hot storage your not going to have that luck.

 

[LargeOrangeFont]

It also depends how much you use the boat. To me more use it will last longer without drying out. Also where you boat, is the water dirty? Do you beach your boat and drag the drive in the sand? Sand dirt will eat up the impeller real fast.

When I install a new one I use dish soap not grease. Do it every other year

This is what I do.

I need to do mine this weekend actually.

 

[Ballyhoo]

for the past 17 years I have replaced the whole kit each year, with exception of 2 years. During that time I have had only one time where the impeller failed. That was a strange one as it only had about 7 hours on it. Twice I replaced it after 2 seasons and both times it wasn't looking very good. Every year for me as its cheap insurance.

 

[SoCalDave]

Thanks, this reminds me to change mine this year as I can't remember if I did it last year.

Anyone running that blue impeller that is supposed to be bullet proof? I think RD said he is using this one in his sled.

 

[lbhsbz]

Avoid using "grease"...use a water soluble lube like dish soap. Impellers are likely EPDM rubber, and EPDM does not play nice with petroleum.

I change my impeller in my OB (Merc 2.4L) every year because it take me 20 minutes and its cheap...unless I jack the motor too high and lose water pressure, my temp gauge stays at 170? (measured in the Starboard head, right behind the thermostat). My dad usually tries to go 2 years on his impeller (merc 2.4L) but on season 2, his temp gauge is ALWAYS on the hot side of the halfway mark, sometimes over the 3/4 mark. With a new impeller, it runs at about 1/4. No numbers on the gauge, so the actual temp is anyone's guess.

I think the issue is that the impeller takes a set and the blades lose tension against the housing...if it's run every day or so the blades should stay pliable since they'll always be flexing and landing in different positions all the time...letting it sit for a month or 2 in 110? heat does not help the impeller stay pliable.

 

[mesquito_creek]

I have never had one actually catastrophically fail per se... Basically they start running hotter than they should, the motor may need to be backed down to bring down temps or conversely, it may not like to idle cool but will drop temp with the forced water induction under way. I have read somewhere that on mercruiser leg the impeller no longer does anything after 20 mph or something like that. I am going to guess that they must just cook and dry out since they live full time in AZ. They always look fine when I remove them but they are "perma bent" into the shape of the housing and must not have the right stuff left in them to flick the water around. I am just amazed people get multiple seasons out of them!

 

[SCV2RVR]

Very first boat was a 1987 Bayliner and I didn't even know what an impeller was until it failed and burned up the motor. I learned very quickly how important they are and how cheap they are compared to a new motor. I sold the Bayliner for parts but now I always replace every 2 years and carry an extra impeller just in case.

 

[SoCalDave]

I think this is the one RD said he was using.
anyone have any feedback?

https://www.gcsmarine.com/content/impellers/impellers

 

[Runs2rch]

I think this is the one RD said he was using.
anyone have any feedback?

https://www.gcsmarine.com/content/impellers/impellers

Curious on these as well.

 

[SoCalDave]

Waiting on RD for feed-back...

 

[bocco]

I think this is the one RD said he was using.
anyone have any feedback?

https://www.gcsmarine.com/content/impellers/impellers

The website sucks. No way to figure out which impeller goes with which drive.

 

[SoCalDave]

The website sucks. No way to figure out which impeller goes with which drive.

yeah, I had to do a google search with the OEM part number and it came up on Amazon. out of six reviews a couple were not good...makes me think to go OEM now and replace every other year.

https://www.amazon.com/Globe-Marine-17954-0001-47-59362A1-47-59362B1/dp/B00CDT4R8W

 

[fishing fool]

One other thing to add.
When you install it make sure it is going the right way.

 

[pwerwagn]

I have a 2.4 that had a ~15 yr old impeller in it, and it never failed. I didnt "intentionally" do that. I had bought a complete motor that was supposed to be good, turned out the lower was trashed. I had already put in a new water pump. I put the powerhead on my old mid/lower, and ran it. I had kind of forgot that the old lower didnt have a new pump. 2-3 seasons later, I thought about changing the impeller and realized what I had done. It worked trouble free for ~14-15 years in all, with about 5-7 years of it sitting. Still had good psi at idle too.

Got super lucky I'd guess.

 

[HitIt]

I posted this thread about impellers last year. Maybe some helpful info?

http://www.riverdavesplace.com/foru...59-Merc-Impeller-replacement-with-Bravo-drive

 

[pwerwagn]

I had never looked in the owners manual for my 300 PM, but i just dug it up to see what it says:


EVERY 300 HOURS OR USE OR THREE YEARS
1. Replace water pump impeller (more often if: overheating occurs,
used in salt water, or reduced water pressure is noted).∗

 

[RitcheyRch]

I have the impeller changed in my Evinrude every other year.

 

[HST4ME]

Anything with a 89980 89981 89982 89983 89984 should be replaced once a year or suffer the perils. Grease, soap, spit, vagasil, KY Iit doesn't matter what you use

 

[ElAzul]

Haven't read anything good about the run dry impellers to date a quick google search will bring up some info

 

[HitIt]

Grease, soap, spit, vagasil, KY it doesn't matter what you use

Astro glide is water based... just sayin...

 

[K-DOG]

We go through them pretty quick at the lower river. Too much sand in the water cause its shallow. I had major scoring in my sea water pump so had to change to the Hardin stainless steel pump which is serviceable when changing impellers.

 

[Rajobigguy]

The last couple of boats that I have owned had Alphas and I have got several years out of each impeller (probably didn't really need to change them at that point either). I think that the reason I get such good life is that I always start the boat at home before heading to the ramp so I'm using the water hose to force water into it. If you just put it in the lake and start you may be several moments running dry before the pump picks up its prime.

 

[nowski]

My last boat had a Johnson pump in it. I first started by changing the impeller every other year. I would always inspect the used impeller coming out of the pump for wear and tear. After two years the impeller looked pretty good so I extended the change interval to 3 years and never had a problem. Note: The Johnson impeller also came with a impeller lubricant grease. The Johnson pump and impeller is a much better designed pump than what Mercury gave us. That Johnson pump had 600 hours on it when I sold my last boat, that pump lasted forever...

Current boat has a 496 mag engine. The 1st thing I did was to get rid of that piece of crap Mercury pump and had a stainless Hardin-marine gen 7 pump installed. In my boat the pump is a real pain in the but to get to, the rear seat is molded in with no access through the seat to get to the pump. I have Hallett change out the impeller for me every other year. A good shop will give you the old parts so you can inspect the old parts for wear and tear. Two years is the maximum change interval for this impeller... Hope this info helps out...

http://www.marinepartssource.com/ne...g=JOHNSON PUMP&desc=Impeller Lubricant Grease

 

[bocco]

Had a house boat on Lake Don Pedro with an OMC king Cobra drive. The boat stayed in the water for six years and the impeller looked brand new. I think if the boat stays in the water the impeller never dries out.

 

[rrrr]

.

On a kinda related note...

How many times have you seen a nitwit pull a boat out at the ramp, then fire it up and rev the shit outta it?

I don't know what they're trying to accomplish, but that destroys an impeller pretty quickly.