Changing water pump on a Mercury Classic Fifty 45hp

[jthomas5150]

Hi,

My boat has been sitting for about three years. Just now found time to pull it out.

I put my water ears on and started up the engine. Engine started right up believe it or not (thank goodness for STA-BIL)! However, no water is coming out of the little hole. I didn't want to let the engine run more than 30 seconds. So I assume the water impeller needs to be changed. I looked all over the internet and can't find too much on the specifics on changing on this exact model. I have never done this before... Side note, the local boat shop replaced the impeller about 4 years ago. Only used it the one year..

I have done my reading and I think I need to learn to do this versus taking it to the shop. Is it as simple as taking off the four bolts and dropping the lower unit? Do I need to have the gear in neutral? Any pointers will be appreciated. Let me know if I am going in the wrong direction here.

J.T.

 

[jimmbo]

There are more than 4 bolts/nuts. There is also one hidden above the Trim Tab, which has to come off. Some people say to put the motor into Forward before dropping the case, others say Neutral. I don't know if it makes any difference. What is important is not to rotate the shift shaft, or move the Remote Control while the case is off.

 

[jthomas5150]

Yes, there were 5 bolts to fool with including taking off the little trim tab!

The lower unit dropped right off. The impeller looked just fine so I reassembled it. Same problem. I finally tried some compressed air and weed eater string to clean out the tell tale and guess what, after a lot of dribbling, it finally expelled water!

Am I okay with reusing the impeller since it looked fine?

Once again, thanks for your help.

 

[jimmbo]

4 years is a long time for an Impeller, whether or not the engine has run

 

[jthomas5150]

Sounds good. I will replace. Do I need just the impeller or a whole kit? Regardless, can someone provide the correct part number? I just want to make sure I get the right part...

 

[jthomas5150]

I can provide my serial number if that helps with getting the right impeller or water pump kit. Thanks again!

 

[jimmbo]

Serial # is always the best/safest way of obtaining the correct parts for Mercs. Usually just the Impeller, baseplate, a gasket or two are needed, but the kit often also includes a new base, with new oil and water seals, slinger washer, and o-ring for the top of the driveshaft, and instructions. Usually it's only a few $ more than the impeller, and baseplate alone.

 

[jthomas5150]

Okay makes sense to just grab the kit if it has instructions! My serial is 0C104585.

 

[jimmbo]

Reference or parts diagram may have been a better choice of words, instead of Instructions. And I did say ‘often includes’

 

[jthomas5150]

Understood. With that said, can you recommend a part number for the water pump kit and I will order it? Thanks again!

 

[jthomas5150]

Hi all. It's been about a week thought I would ask again, with my serial number being 0C104585, can someone recommend a good water pump kit to order? Thanks!

 

[jimmbo]

47-89983T is what I come up with, but I would call a Merc dealer to verify