What is this white nylon insert in the mouth of my lower unit??

[joe3buck3]

2017 Mercury 115 Pro XS Ser# 2B442155
Was changing lower unit lub today and when I removed the prop I found this white nylon ring loose just inside the mouth of the lower unit. It has small tabs that are probably supposed to snap/lock it in place but they are not. Is there a trick to securing this thing or can it just sit loose inside behind the prop? Sorry about the sideways pics.

[bassbama]

A protector for the carrier nut and case/threads. Doesn't take a whole lot of sand or debris to dislodge it (pretty close tolerance, especially with the FT-III hub kit). It does snap into place but not very well I keep a couple on hand and install a new one when I pull the prop for maintenance they are cheap $ wise. Mercury calls them a (sleeve-prop bore) I would give you the part # but I have a 150 not sure if it's the same.

[joe3buck3]

Thanks bassbama.

Is this the correct Mercury part number for the (Sleeve, Propeller Bore) 23-8M0054695

[bassbama]

Thanks bassbama.

Is this the correct Mercury part number for the (Sleeve, Propeller Bore) 23-8M0054695

If you launch Mercury parts express and input your serial number it shows 2 possibilities depending on your gear ratio. The part number is stamped on the inside lip of the sleeve/prop on the one you have now hard to read may have to clean the plastic and use a flashlight to make out the numbers it will be the inside lip facing you when it's installed.

[joe3buck3]

thank you bassbama. I ordered two today.

[tin wacker]

Mine came loose so I took a cigarette lighter and bent them out a little bit after heating it haven't moved in 2 years

[joe3buck3]

tin wacker
Thanks for the recommendation on heating/bending the part. I tried that last evening and it worked perfectly. I was a little surprised when I heard and felt it SNAP securely in place after it was totally loose. I did order two replacement/spares as they are inexpensive but I may never need them now.

[bassbama]

Gonna try that tip Tin Wacker thks

[EuropeanAM]

Having a spare is definitely a good idea.

And though it can be a bit annoying, it is good to see that it apparently did it's job (and protected the bearing carrier bore from damage).

[tjsellsfords]

Thanks for the input on this subject I've been wondering about mine it's been loose as well.

[joe3buck3]

The part number for the 2017 Mercury 115 Pro XS sleeve prop bore is: Quicksilver 8M0070256