1st easy check, is there a rope wrapped around prop? My IO did and melted some of the rope into a disk between prop and lower unit, tearing the prop seal.
I had overcharging problems with my 850 Merc. It would climb to 17 volts at 4k rpm, boiled the battery. I replaced the rectifier with a 6 wire regulator. 14.5 volts at any speed above 2k rpm. It has a Tach wire too. I had to get creative with mounting.
3/4 inch Exterior ccx under vinyl is the way I went. Use 1/2" risers under railings is the key for water shedding. I also shimmed furniture and helm with ridged plastic.
The old deck lasted 20 years under carpet and No risers.
Spline isn't lined up with upper half. Try turning prop while holding pressure on lower unit. You DO have both the Helm and lower in forward gear, right?
Never had satellite, never had cable, never had Internet programs. I remember not having a Television until 7 years old. Yep, I'm old, 77. My OTA 22-27 channels is a bonus from the 50's 3 black and white shows.
The old wiring is 16 gauge. Couple of years ago I'd spliced (soldered) a cable (8 wire 14 gauge) into the old 6 " from engine female coupling. Thought the wires from there to coupling were good (wrong). I'm running a 14 gauge wire from console to switch box (summer) is here 😊
1975 '850' . Type III the ignition wire is broken or corroded inside the wire loom from console to engine. I'm getting flaky voltage to the ignition post on switch box. I ran a 16 gauge from ignition switch to switch box and all is well. Engine started quickly.
Question: Is 16 gauge X 12'...
Two re-decks on my 24ft 1979 Harris Flote-Boat. 1st was carpet. Once you go vinyl you never go back😉. 1975 Mercury 50hp. Helm has Tach and Volt meter.
There are too many 300hp Tri-toons on our 1 mile by 7 mile Buckeye Lake.
An automotive carburetor has a linkage driven "Accelerator Pump" which sprays, enriches fuel mixture when pedal is pushed quickly. You won't see this on the Merc because fuel is Vacuum drawn thru the carburetor.
My 1975 (850) wiring was past toast. I had to replace everything. Mercury corporation must have subcontracted the harness on the cheap for several years 🤐
