New Impeller, then Overheat Warning

[gjcombs]

All,

I did the right thing by getting the Quicksilver impeller and seal kit for my Alpha 1, Gen II. I replaced it and put the lower unit back on, etc...
http://forums.iboats.com/showthread.php?t=391127

I put the muffs and water on (half-flow) and it seemed to run great. After 5-8 minutes the overheat warning came on so I shut her down right away.

I pulled the lower unit to check if something was wrong with the impeller. I found fine rubber pieces about the pump housing, so I thought it was shredded or something. However, it still appeared in good condition with some of the edges burred. The wall inside the housing is smooth, so OK.

The overheating most certainly has to do with what is I changed out.

Therefore, is it OK to push as much water as I can through the muffs? Would a trashcan or container system be a better way to land test it?

What else should I check?

Could be similar to this post?
http://forums.iboats.com/showthread.php?t=392793

 

[RL Gman]

Re: New Impeller, then Overheat Warning

was there a lot of water coming out of the propeller exhaust port?

 

[gjcombs]

Re: New Impeller, then Overheat Warning

No there was not.

I am thinking that the muffs were not sealing right around the uptake ports. The engine sounded fine; the manifolds were definitely hot.

 

[RL Gman]

Re: New Impeller, then Overheat Warning

If the muffs were over the intake, it should have been sucking water. Doesnt sound like water is getting through the engine. Was there water coming out near the transom? If you ran it for 5-8 minutes, plenty of water should have been coming from the transom...

Little pieces of a new impeller bother me...what would make a new impeller shread? Were the blades all facing the correct direction?

Yes, go ahead and open up the water to full flow, but the muffs should be find to idle and engine, and it shouldnt overheat...my 5.0 doesnt...

 

[gjcombs]

Re: New Impeller, then Overheat Warning

I know exactly what you mean. I checked the impeller direction and they were right.

I will cautiously try it again and see what is up. If the same thing happens, I'll pull it again and check the impeller another time. I need to take a picture this time.

 

[RL Gman]

Re: New Impeller, then Overheat Warning

Have you tried yet? I'm interested to hear the outcome...

 

[gjcombs]

Re: New Impeller, then Overheat Warning

Thanks for the inquiry.

The system ran fine after inspection. I even pulled the thermostat and stove top checked it to see that it was opening and closing at the rated temps.

It could have been any the following:

1. I did not have the muffs completely on right. I paid closer attention to placement this last time and that there was a draw from the pick-up pump.
2. I seem to recall not much water coming out of the transom. However, I paid close attention and there was water this time, and it was warm.
3. The temp did got up to about 178-180F. This it where it should be based on the range of the thermostat. It did not get hotter.
4. My alarm could have gone off inadvertently from a slug of hot water from starting, stopping and restarting and with the combination of the muffs not delivering.

In other words, I don't have a conclusive answer, but do know that it stayed in the temp range and the alarm did not go off.

The impeller looked in good shape. In fact the old impeller looked in good shape too and I think was the original. It was stamped as 1993 and I have a 1994 drive.

 

[RL Gman]

Re: New Impeller, then Overheat Warning

Thanks for the inquiry.

The system ran fine after inspection. I even pulled the thermostat and stove top checked it to see that it was opening and closing at the rated temps.

It could have been any the following:

1. I did not have the muffs completely on right. I paid closer attention to placement this last time and that there was a draw from the pick-up pump.
2. I seem to recall not much water coming out of the transom. However, I paid close attention and there was water this time, and it was warm.
3. The temp did got up to about 178-180F. This it where it should be based on the range of the thermostat. It did not get hotter.
4. My alarm could have gone off inadvertently was a slug of hot water from starting, stopping and restarting with the combination of the muffs not delivering.

In other words, I don't have a conclusive answer, but do know that it stayed in the temp range and the alarm did not go off.

The impeller looked in good shape. In fact the old impeller looked in good shape too and I think was the original. It was stamped as 1993 and I have a 1994 drive.

Good news that it's working! Congrats.

I thought this was an important thread to close out, most first time DIYers start with the water impeller! I'm guessing what you found will help some new DIYers in the future!