Well Duh !!

[spdracr39]

Made an oops today. In the frenzy at the dock I loaded the boat and signaled the driver to pull up about 100 yards to secure everything like always. I remembered to trim the drive up first but I never shut the engine off. It ran at idle for about 30-45 seconds before I realized there was an abnormal sound and turn it off. I didn't smell any burning rubber or plastic at the exhaust afterwards.
Question 1 : do you think I cooked my brand new impeller?
Question 2 : will it run hot on the muffs if the impeller is in fact bad ?

 

[oops!]

Re: Well Duh !!

you cooked your impeller......it only takes 3 seconds.

one of the problems is that when you are hooked up on the muffs.....the water pressure from the hose is forcing water thru the motor....so you cant tell if the impeller is cooked on the muffs..only on the water

you need to change it.

 

[mpdive]

Re: Well Duh !!

Agree with OOPS. Change the impeller. Look at the bright side, at least you didn't turn off the engine and leave it trimmed down. Could have been worse. Happens to the best of us.

 

[90stingray]

Re: Well Duh !!

Impeller is gone. We've all done it, so change it and be done with it. Also, don't be running your engine with the drive trimmed to trailer position. That's prolly where all the noise was coming from... its hard on the ujoints.

 

[spdracr39]

Re: Well Duh !!

I didn't have it all the way in the trailer position just at the top of the regular up position. If I had done that I would have remember to turn the silly thing off Fortunately that's all it
takes to clear the ground.

Now for some education. How exactly does the exhaust come back through the impeller? Shouldn't it go the other way? Especially on a cold motor with the thermostat closed ( I know mine wasn't just curious).
I can't get any parts till Tuesday so I'm gonna see if it is really hurt before I tear into it. The impeller was really first time out brand new. I ran the boat for about 30 minutes in a bucket and the water appeared to flow normally and the temp never got above 165. I revved it to about 1500 and it sucked the water like normal. Tomorrow I'm gonna put it in the water
and test it near the dock. I'll have friends around to tow me if necessary so the risk is minimal since I know it is pumping some water. I'll post the results afterwards. I hope I can at
least see how vulnerable the impeller really is in this circumstance.

 

[slag]

Re: Well Duh !!

Your impeller wont cook after 3 seconds. There was probably enough residual water in your outdrive. Now, a minute? sure, probably toast, but not after 3 seconds and not after 10 seconds either. Working at a marina part time in the past, I've seen both outboards and inboards that have been run out of the water for 10 seconds and there has been no damage to the impellers.

 

[Don S]

Re: Well Duh !!

Your impeller wont cook after 3 seconds. .

He didn't say 3 seconds,

It ran at idle for about 30-45 seconds

 

[spdracr39]

Re: Well Duh !!

What do you think I'll find ? I expect it to be ok at idle and run hot at speed. I'm not trying to get out of changing it just trying to learn something from it ( beside turning the motor off on time ).

 

[Don S]

Re: Well Duh !!

What do you think I'll find ?

What's the difference what we THINK it might look like, take it apart and look. Being a Gen II, it won't be as bad as the earlier pumps.

 

[egclassic]

Re: Well Duh !!

He didn't say 3 seconds,

Yeah, but he did!

you cooked your impeller......it only takes 3 seconds.

one of the problems is that when you are hooked up on the muffs.....the water pressure from the hose is forcing water thru the motor....so you cant tell if the impeller is cooked on the muffs..only on the water

you need to change it.

 

[Eric 3.7LX Alpha 1]

Re: Well Duh !!

I didn't have it all the way in the trailer position just at the top of the regular up position. If I had done that I would have remember to turn the silly thing off Fortunately that's all it
takes to clear the ground.

Now for some education. How exactly does the exhaust come back through the impeller? Shouldn't it go the other way? Especially on a cold motor with the thermostat closed ( I know mine wasn't just curious).
I can't get any parts till Tuesday so I'm gonna see if it is really hurt before I tear into it. The impeller was really first time out brand new. I ran the boat for about 30 minutes in a bucket and the water appeared to flow normally and the temp never got above 165. I revved it to about 1500 and it sucked the water like normal. Tomorrow I'm gonna put it in the water
and test it near the dock. I'll have friends around to tow me if necessary so the risk is minimal since I know it is pumping some water. I'll post the results afterwards. I hope I can at
least see how vulnerable the impeller really is in this circumstance.

The exhaust isn't going to. The impeller gets damaged by the friction, and it being so tight in the water pump housing and there not being water there to keep it cool. It will probably burn the rubber veins of the impeller and make them hard and stiff instead of flexible.

 

[Fordiesel69]

Re: Well Duh !!

You think your stupid???? I had twin engines & drives. I hooked up muffs to the port engine, ran it a bit. Shut it off and the hose water. Never transfered the muffs to the starboard drive, turned the water back on, heard it trickling and ran the starboard engine.......roasting my brand new impeller & housing!!!!!!!

I would recommend NOT running the engine to test. As of now the impeller pieces are all in the housing and tube. If you force water thru it, you will blow all the pieces into the engine and you will require a lot of disassembly.

 

[slag]

Re: Well Duh !!

He didn't say 3 seconds,

I was replying to Oops post, not the OP's.

 

[spdracr39]

Re: Well Duh !!

Well the lake trip was a success!!! High speed, low speed, and pulling a tube the temp never got over 170. I'm not saying I didn't just get lucky but I think the lesson here is not to jump to conclusions. Why make a repair when one is not needed. Do a little testing and make an educated decision. I really appreciate everyone's advice and I was listening but I needed to confirm my instinct that it was not damaged and I felt it was worth the risk.

 

[NHGuy]

Re: Well Duh !!

I'm glad for you. And not that surprised.
Example, this weekend I put a new starter in the boat, had my daughter turn on the water to the muff, observed it flowing around the muff and started it a couple of times. I shut it off right away each time.
Then I get called to supper, I'm climbing out of the boat, what is laying on the ground? The hose had popped off the muff.
I put it in the water and all was well.

 

[jayrodoh]

Re: Well Duh !!

Well the lake trip was a success!!! High speed, low speed, and pulling a tube the temp never got over 170. I'm not saying I didn't just get lucky but I think the lesson here is not to jump to conclusions. Why make a repair when one is not needed. Do a little testing and make an educated decision. I really appreciate everyone's advice and I was listening but I needed to confirm my instinct that it was not damaged and I felt it was worth the risk.

Glad it worked out for ya, I for one would've changed the thing as I don't like surprises at the lake and ending my day short. Although I've changed mine a few times and it's no biggie anymore either.