Did I ruin the impeller

[crawleym]

I took the boat out of the garage the other day wanting to turn over the engine and warm it up for a bit to check it out. I hooked up the ear muffs, started the water and then started the engine.

Unfortunately, I stopped the engine and then a little while later started again. The second time I had fogot to turn on the hose before starting the engine. It ran this way for may be up to a minute before I realized what I did and I hurried up and turn on the water supply.

What are the chances that I ruined the impeller?

I've done a test of putting the lower unit in a large container of water and it is still drawing water through the engine and the engine temp remained good. But I'm concerned that I may have an impeller problem waiting to happen.

 

[Bondo]

Re: Did I ruin the impeller

What are the chances that I ruined the impeller?

Ayuh,... About 99.875%....

 

[guyaverage]

Re: Did I ruin the impeller

I did the exact same thing last year, I was running mine and shut it off, then hopped out of the boat and shut the water off. I got back into the boat, adjusted the belt on the alternator, then restarted the engine. I walked to the back of the boat, leaned over the back, and noticed OH CRAP no water. I quickly shut it off. It only ran without water about 15-20 seconds. Pulled the drive, the impeller was fine.

If you ran yours without water for what was really a minute, I doubt you'll be as lucky as I was. I agree with Bondo, its probably toast.

 

[crawleym]

Re: Did I ruin the impeller

So I just replace the impeller? The water pump itself should be good. I assume they sell a kit?

 

[achris]

Re: Did I ruin the impeller

If the impeller is melted (very likely) then it got melted because of heat. I know that sounds obvious but you wouldn't believe some of the things I've heard people say.... If the impeller got hot enough to damage it, the PLASTIC housing is also going to be melted... That will need replacing too... And the base probably copped a bit too, so get a new one of those in...


Chris........

 

[Sean-Nos]

Re: Did I ruin the impeller

Have a look at this guy,You might be ok as yours was wet to start with but no harm in changing it anyway better safe than sorry.
http://www.youtube.com/watch?v=MsCCPUUXbGE

 

[bruceb58]

Re: Did I ruin the impeller

If the impeller is melted (very likely) then it got melted because of heat.

True if its a mercruiser...not true if its a Volvo.

What does the OP have in this case?

 

[crawleym]

Re: Did I ruin the impeller

Good news is that I did not ruin it. I just spent the last 2 hours separating the lower unit from the top. Most of the time was just waiting for the oil to drain and contemplation. The impeller is just fine. Rubber is flexible and does not show signs of wear, stiffness, burns, etc. Quit honestly I'm surprised the impeller survives in the first place. I would think the friction, even with the water cooling would cause it to rapidly deteriorate.

Now all I have to do is re-assemble and re-fill the lube. I figure another 30 minutes to do so. I hope that I re-assemble everything correctly as not to cause additional problems. I feel a little brain dead that I did this in the first place but something tells me I was not the first.

I've been wanting to learn/practice doing this. Now if the impeller breaks at the lake I will be able to repair it without delay. Plus I'll be able to do this myself in the future. I called the boat shop and they wanted $320 to replace the pump with parts&labor. I now just saved myself a few dollars and kept myself entertained. Now to purchase the oil pump and a couple quarts of quicksilver lube/oil.

 

[Don S]

Re: Did I ruin the impeller

It did not take all that much time. I've been wanting to learn how to do so because I'd like to change the impeller myself the beginning of each season. The boat shop wanted $320 for parts in labor but that included some other stuff because they wanted to remove the upper unit as well.

There is a reason why they wanted to pull the complete drive for "Other things" that really need to be done. You should also be doing the impeller in the fall during winterizing, etc. etc.
Might want to start a new thread about what you want to do to find you are missing a lkot of what really needs to be done to your boat,

I posted this on your other post in the fragile impeller thread.

Your impeller should be replaced in the fall when you pull your drive to check for water in the bellows, checking the alignment, greasing the coupler splines, greasing the ujoints, cleaning up around the gimbal bearing after greasing, and in general checing things out. That should be done EVERY YEAR. Since you will be changing the gear lube in the winter, or at least you should be, why have to drain the new lube out in the spring to change your impeller. Do the whole job in the fall. Then you have the drive off the boat, and it makes everything a lot eassier to assemble, and EVERYTHING gets checked and inspected, and new oil in the drive,

 

[crawleym]

Re: Did I ruin the impeller

I posted this on your other post in the fragile impeller thread.

Your impeller should be replaced in the fall when you pull your drive to check for water in the bellows, checking the alignment, greasing the coupler splines, greasing the ujoints, cleaning up around the gimbal bearing after greasing, and in general checing things out. That should be done EVERY YEAR. Since you will be changing the gear lube in the winter, or at least you should be, why have to drain the new lube out in the spring to change your impeller. Do the whole job in the fall. Then you have the drive off the boat, and it makes everything a lot eassier to assemble, and EVERYTHING gets checked and inspected, and new oil in the drive,

Agreed. I bought the boat used very late in the season (beg of Sep) last year. Immediately took it to a professional mechanic. Had all work done including replacing the bellows which was bad. I only used the boat a few time and then put it away in the garage for the winter. The mechanic said I would be good until the end of next season. I was just checking the impeller since I thought I toasted it. Turns out I did not so I figure every thing is good until the end of this upcoming season if I just reassemble it. Am I incorrect?

 

[ziggy]

Re: Did I ruin the impeller

Turns out I did not so I figure every thing is good until the end of this upcoming season if I just reassemble it. Am I incorrect?

i think ya should replace the impeller. your right there able to touch it and you know it's not the easiest item to go get. cheap insurance that it's not damaged.
here's a link for ya... http://www.boatfix.com/merc/Bullet/87/87_14.pdf
i'd agree with that link and find it hard to believe ya didn't damage the impeller.

a pic of three years of impellers. all replaced at end of season. they all got curl to them. they were all abused at least once. if i remember right. 2 of them ran w/o water for a moment, the worst looking one ran on low water flow till minor overheat.

this one is the one ran on low water flow. smoke acutally came out of the drive. i did run it till end of season. but i watched my temp gauge like a hawk as i couldn't help but think i'd damaged it. and i did.

after one years use, all these impellers look like there not up to snuff to me.
note cracks on inside of curl. on the over heat one. there was rubber loss.

ya know, after rubber gets hot it's not as pliable as it was before being heated up. it gets hard. and the impeller vanes do need to be able to flex as the blades get compressed every revolution they make. a new $25-#30 impeller could give you piece of mind..

 

[achris]

Re: Did I ruin the impeller

We didn't ask... What year is the engine/drive?

If it's 1991 or later, then it's a Gen II, and that would explain the 'luck'. The floppy vane impellers in the Gen IIs is a lot more forgiving of abuse (dry running)...

Chris.........

 

[crawleym]

Re: Did I ruin the impeller

It's an 1995 5.0LX (GM) - Alpha Gen II. On an Bayliner 2050 LS.

 

[crawleym]

Re: Did I ruin the impeller

Here is a picture showing old vs new impeller.

 

[MRS]

Re: Did I ruin the impeller

If your down that far you should just change it now but it looks like you got the new one in the last photo you posted. Change it and have fun this spring.

 

[Don S]

Re: Did I ruin the impeller

That's why it helps when someone says what drive they actually have. You don't have any plastic housings with an Alpha I Gen II outdrive. Put the new impeller in and go boating. (new gaskets also).
Those impellers put up with a lot more than the older generation Alpha and one drives do, but your impeller is damaged. The fact that it isn't uncurled says the heat got to it.
Out on the water, that impeller would probably work fine, buy why try to find out how long.

 

[ziggy]

Re: Did I ruin the impeller

That's why it helps when someone says what drive they actually have.

yep, everything i said is not relevant.

my buddys have genII drives. my observation from theirs is it seems like they last much longer than the alpha1 versions... it was a good upgrade from the alpha1...

 

[crawleym]

Re: Did I ruin the impeller

I bought and installed the impeller kit. The peace of mind will be worth the few dollars it cost me. Thanks to all on the advice.

 

[ktmrider]

Re: Did I ruin the impeller

I must be the dumbest person on here....

I ran the boat out of the water without water two times for 5 minutes each time....

Apparently, I thought it was like a car.

My wife even warned me about this!
Took the boat out yesteday....5 minutes later I smell something and nootices smoke coming out of the engine....

We got it back to shore....the engine still starts....
I nope the impeller is the only problem.
but the exhaust riser area was very hot!

 

[Don S]

Re: Did I ruin the impeller

You may very will have some other problems, I would suggest you start a new thread regarding what may have happened.
Best not to hi-jack crawleym's thread with questions about your boat, gets confusing and your thread gets covered up.