2001 Mercury 115 FOURSTROKE Water Pump Service

Repair or modification of Boston Whaler boats, their engines, trailers, and gear
eyedol911
Posts: 2
Joined: Mon May 30, 2022 7:51 pm

2001 Mercury 115 FOURSTROKE Water Pump Service

Postby eyedol911 » Tue Sep 27, 2022 1:17 am

Q1: [Implied] How is the water pump serviced on a 2001 Mercury 115-HP FOURSTROKE engine?

BACKSTORY
I have 2001 Mercury 115-HP FOURSTROKE engine on a 2001 16/DAUNTLESS. After removing the lower unit, I found a rubberlike covered metal sleeve in the middle of the driveshaft. The water pump cover cannot be removed until the sleeve is removed. The sleeve is 6- inches above the water pump cover, about 1.25-inches wide.

The rubberlike material looks partially burned.

[The link below show some unidentified outboard engine with a drive shaft extension but without any sort of rubber sleeve as described above]

https://imgur.com/a/NoddQD1

jimh
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Location: Michigan, Lower Peninsula
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Re: 2001 Mercury 115 FOURSTROKE Water Pump Service

Postby jimh » Tue Sep 27, 2022 5:48 am

If you plan to perform service on your engine yourself, buy the factory service manual. The factory service manuals generally provide excellent advice, particularly on procedures that at first glance by an untrained person may appear to be impossible to perform.

ASIDE: in 2001 I do not recall that Mercury could manufacture any four-stroke-power-cycle outboard engines at a 115-HP level. At that time, Mercury was buying thousands of power heads from Yamaha to be rebranded and sold as Mercury engines.

The engine you have is probably an engine with a power head made by Yamaha mated to a midsection and gear case made by Mercury. As a result, there may be some rather unusual mechanism required to couple the drive shaft from the power head to the drive shaft to the gear case. The coupling you describe in your narrative may be such a device.

I have looked at the image with no caption that you have given a hyperlink to, but I do not see any coupling that corresponds to your description. Please explain what readers are to see in the linked image and why it does not match your description.

eyedol911
Posts: 2
Joined: Mon May 30, 2022 7:51 pm

Re: 2001 Mercury 115 FOURSTROKE Water Pump Service

Postby eyedol911 » Tue Sep 27, 2022 8:52 am

Thank you for the thoughts.

I have uploaded another picture that you can see clearly. There is a band-look-alike part is attached in the middle of the driveshaft. Also, rubber-like part is on bottom of the picture. The band-look-alike part has a crack in the middle.

https://imgur.com/a/NBD4PKw

You are right—this might be a Yamaha motor branded as Mercury. I remember that when I installed a water temperature sensor, I had to look for Yamaha part.


Thank you very much again. Please feel free to post any thoughts and I appreciate it very much.

PS: I just spoke with Mercury outboard service. They thought this object might be the sleeve or ring lodged in the driveshaft. That is most likely, but I have never seen it before.