PLEASE HELP with Merc and Outboard jet

[CatfishingMo]

I recently purchased a used outboard jet to replace the prop lower unit on my '77 Merc 50 horse. After I recieved the jet and started comparing the 2 I noticed some differences. I looked on the Outboard Jets Co. Website and it seems the jet should work. It originally came off a 1965 50 horse and both 65 and 77 show the same part number, but I'm not sure. The exhaust downpipe is to long and does not fit the factory hole in the jet unit. Also the two side by side front mounting bolts match but the rear do not. The jet is only designed to have one rear mounting bolt which it has and is a stud sticking up supposed to go through the center section of the motor with a nut on top. The prop unit had a bolt that went through the lower unit and into the threaded hole in the center section. The hole in the center section is to small for the stud to fit. When I look on the outboard jets website one of the footnotes is, "Drill Kit Needed". The stud sticking up is long enough to go completely through the lower leg and have a nut on top. Was it meant to be drilled out bigger for the stud to go through? If it weren't for the shallow shoals on the rivers around here I'd just leave it a prop but if I wanna fish I gotta have a jet. Any info or advice would be appreciated Thanks

 

[Lone Duck]

Re: PLEASE HELP with Merc and Outboard jet

Catfishingmo:
Yes! the bolt goes through the lower leg with a nut on top. If you can, use stainless steel studs and nuts. Check with shops around the country to advise you about the exhaust. Before you carry on with this, take the time and google ( outlaw marine jets, outboard jet maintenence, enhancing outboard jet performance, F A Q's jet pump and snyder boats)
All have articles that will give you an idea of what you are getting into. I have a 22' flat bottom boat with a 1982 90hp merc IL6 outboard jet. I can run in 4" water at 3/4 throttle . It is a blast man. remember jets are a whole different ball game than a prop. Also check your numbers on the jet foot ( they are on the side where the reverse cable goes) Find out from the manufactor what changes you might have to make to obtain replacement impellers for it. It will depend on the age of the jetfoot. The newer ones come with a different key than the older ones and most have a kit for the difference . Happy jetting.