Mariner 3.5 hp Lower Unit Removal

[ragnar333]

I've got a little Mariner 3.5 here, I think from the early to mid 80's. The tag has 642 S 032734 on it. Anyway, I just started it and it wasn't pumping water so I'm in the process of dropping the lower unit to replace the impeller. So far I've removed the 14mm nut and the 14mm bolt, and the little 8mm at the back near the exhaust port. It dropped down about 1/2" or so easily but stopped, I'm assuming because I have to address the shift linkage. Do I just disconnect the shift shaft through the adjustment window on the leg, where the clamp joining the two shaft sections is, under the rubber plug? Thanks in advance for any input.

 

[minuteman62-64]

Re: Mariner 3.5 hp Lower Unit Removal

If it is similar to my 30 HP, of the same era, the upper and lower shift shafts are joined by a coupling nut that is visible in that window in the leg. You just unscrew that coupler and the shift shaft sections separate.

If it is similar to mine, and the coupling nut hasn't been disturbed for a number of years, and it was assembled without anti-seize or similar substance, the coupling nut will be frozen and you will have to use heat/penetrating oil to loosen it. Alternative is to disconnect the upper shift shaft, somewhere up inside the lower cowl.

 

[carholme]

Re: Mariner 3.5 hp Lower Unit Removal

Your s/n comes up as;

3,5 M 642-026311 - 1980

From here:

Mariner 2 - 8 hp, produktions?rslista, modellguide

Parts List:

3.5 H.P. - Mercury, Mercruiser, Force, etc. Parts Lookup

Gerry

 

[ragnar333]

Re: Mariner 3.5 hp Lower Unit Removal

Well, I got the lower unit off and I feel like a real dope. This thing didn't pump water because it doesn't have a water pump. It's one of those air cooled models.