Re: Mercury Mark 5 Lower Unit

[hotrod]

Another consideration from a Merc service manual: The original Mark 5 gearcases were machined deeper where the prop shaft ball bearing seat is. Thus they used a spacer between the ball bearing & the seat. The "replacement" housings were not machined as deep for the seat and this eliminated the use of the spacer. You will have to figure out if you need the spacer or not.
(The 2 needle bearings were used in the KF5 & MK5 & MK6 gearcases but only illustrated in the KF5 parts illustration.)