Six Questions: 17-footer with 90-HP

[heatxcape]

Q1: has a 17-foot classic hull ever been powered by a115-HP engine with a 25-inch shaft?

Q2: if, so was the 115-HP engine mounted high?

Q3: was it mounted with a bracket?

BACKSTORY: my son’s 17-footer has a Johnson 90-HP engine that is fighting us. The power tilt-trim is not working. The prior owner broke two of the four bolts on the pump and replaced them in holes with 5200 adhesive or some similar adhesive. I got out the others. A replacement new tilt-trim may cost more than $300. I found for sale locally for $500 Johnson 115 with a 25-inchshaft. Wrestling with just swapping out engines.

Q4: are there concerns about using the 115 engine?

Q5: how can the broken bolts be repaired?

Q6: tell me how to install a new trim pump.

[Oldslowandugly]

I think adapting the 25 inch shaft is more trouble than it is worth. If the 90 hp is otherwise working perfectly I would concentrate on fixing the tilt pump. First I would take the pump off and disassemble it. Clamping the pump body in a vise and trying to get the broken bolts out will be a challenge. Drills, easy outs, heat, all will be needed. But if you manage to get it out then they sell a rebuild kit for the pump and that would be my plan. That assumes the pump was not corroded and is serviceable. If not a whole new pump would be in order and then you would be back in business relatively easily.

[heatxcape]

[I am] finally coming to my senses. [I am] planning on pulling the trim-tilt unit—if i can get the bolts out and [I am ] confident it will very difficult. [I] will need every tool in my garage to get off the bracket. [It is] the best course of action

i found used trim-tilt assemblies for under $300 that should work.

Wish me luck and prayers [so I] can get off this bracket.

[Oldslowandugly]

Good plan. When I had to remove my tilt assist the biggest hassle was getting the long mounting bolt out. That is the one that goes through both side brackets and the unit mounts on. It is under saltwater almost all the time. Mine was horribly corroded, the nut was stripped, and it took a long time to cut the nut off and pound the bolt out of the bracket with a big drift. I replaced the tilt assist with a new one that only lasted about 10 years. It was charged with nitrogen and when it leaks out the whole unit is junk. When that one failed I found an NOS power trim-n-tilt on Ebay for $1000. Now that one is almost 10 years old too but I know I can at least re-build it unlike the assist. You could get lucky and get a good used unit. But if you found an NOS or re-built pump with a warranty that would be a lot better.

[biggiefl]

A 25" shaft will not work on a Montauk with out a jackplate. A $500 engine is probably a piece of scrap metal and would not buy it. You should be able to get a whole assembly used for $200 or so. Yes it is usually not the easiest of jobs, nor the hardest.