1958 Mercury Mark 28

[tiercelhybrid]

I recently purchased a 1958 Merc Mark 28 for use on a CU-42 Wetback 3-point Hydroplane I am building. The engine runs, but doesn't spit water out of the "pee hole", and overheats quickly. I am seeing on the forums that the impeller replacement is no easy task, and requires some factory tools to complete. I have purchased a Sierra #18-3008 impeller from the local NAPA parts store, but need assistance to make the repair. What else should I be aware of regarding this particular outboard?

 

[rivermouse]

Re: 1958 Mercury Mark 28

Its no big deal to replace the impeller, Just remove the foot and shifter connection and the cover for the pump and replace the impeller,,Not hard at all after you do it several times It is a one hour job or less. You may need a spanner wrench . If you dont know what that is Im afraid it may very well take you a little bit longer than a hour.Best of luck

 

[Chinewalker]

Re: 1958 Mercury Mark 28

Actually, not so easy as that. The Mark 28 is a unique bird - has an "automatic transmission" in place of a more tradtional clutch dog gear shift. This puts the impeller high up in the motor leg and difficult to get at with shadetree mech tools.
You might find this useful...
http://www.pfs-ware.com/WhitePapers/pdf/AutoTrannnyRepair.pdf

 

[rivermouse]

Re: 1958 Mercury Mark 28

My bad, I was thinking it was like the 60 models ,

 

[tiercelhybrid]

Re: 1958 Mercury Mark 28

Thank you for the information on replacing the impeller on my Mercury Mark 28. Seems like I might have made a poor choice to power my just completed Hal Kelley 10 foot 3 point Wetback hydroplane.

Does anyone know if it is possible to attach a remote control throttle to the 1958 Mercury Mark 28 Super Hurricane??

 

[merc850]

Re: 1958 Mercury Mark 28

The guys on this site work on and own motors just like yours: http://johnsoldmercurysite.com/phpBB3/index.php

 

[Chinewalker]

Re: 1958 Mercury Mark 28

Thank you for the information on replacing the impeller on my Mercury Mark 28. Seems like I might have made a poor choice to power my just completed Hal Kelley 10 foot 3 point Wetback hydroplane.

Does anyone know if it is possible to attach a remote control throttle to the 1958 Mercury Mark 28 Super Hurricane??

It is certainly not the best choice for a remote hook-up with a deadman throttle. You are using a deadman throttle, yes?

Actually, the powerhead on those Mark 28s is a good one. It was built in one form or another up to about 1979. With a little ingenuity it can be adapted to a direct drive Mercury lower unit from an old KE7/KF7/KG7/KG4 which gives you a bit more high perf prop selection and a lot less weight and complexity. Poke around looking for Merc Rat Racers. It's a lot less expensive than trying to track down a Quicksilver unit... Johns Old Mercury site is a good starting point as several of the guys there have built Rats with good success.

 

[tiercelhybrid]

Re: 1958 Mercury Mark 28

Chinewalker,

You obviously have a bunch of experience with Mercury outboards, and the Mercury Forum. As a sixty-something guy, I am stuggling just to participate and post stuff on the forum, and then find my way back to the site to collect responses to my questions. Is there any way to directly communicate with you via e-mail, or is that not cool? My e-mail address is tiercelhybrid@yahoo.com

I am completing a hydroplane project with my 12 year old grandson. It happens to be the same hydroplane (CU-42 Wetback three point) that my dad and I built back in the 60's when I was 14 years old. It was powered by a 1957 (I think) Mercury Mark 25 that had a similar twist-grip control as the 1958 Mercury Mark 28 that I recently purchased for this new project. I did manage to find a vintage "deadman's throttle", for which I paid $25.00. I do believe that I must have had my old boat controlled with a "squeeze throttle", but it may have been utilized with a Johnson 10hp on a MiniMax hydroplane, which was the first boat that my father and I constructed when I was 12 years old.

Keep the responses coming as I am presently fiberglass taping the hydroplane in preparation of launching in the next week, or so. I will power it with a 9.9 Johnson until I can get the Mark 28 operational, and find a flush-mount steering wheel for less than the coast of a new one from Clark Craft (which is over $200.00.