just plain ole Bill
Seaman
- Joined
- Aug 7, 2007
- Messages
- 55
OK guys, you've brought me a long ways on this old boat. Time for another coaching session:
Installed a universal OMC tach. Boat had been rewired so nearly all wires under dash are red. Previous owner had also replaced control box so all wires (except grey) were spliced near control box. The grey wire was cut and just left disconnected inside sheath covering splices. I spliced it and ran it as the SIG wire to the tach. Hooked up remaining wires to tach and fired it up and no tach display. (The tach had been pulled from the dash and a cup holder covered the mounting hole.) Found a green wire that energized when the key switch was turned on so I tapped it for the BAT connection. OOPS! (This doens't work well on a '72 65hp with an electric shift) Moved over to the wire that energizes the choke. Now I have a tach reading with the Forward button pressed.)
Problem is tach seems to work well except around 1K. At around 1K the tach jumps up to 3K without any change in engine speed. If I idle down a little the tach drops to a normal reading.
I thought the tach was supposed to be set on "6". When I hooked it all up there was no reading. I dropped it to the "5" setting and it seems to respond correctly except for the problem around 1K.
A side note is that since I installed the tach the lower unit will not shift. I checked the voltages where the wires drop into the lower unit to the solenoids and they are correct as the different buttons are pressed. And nautrally, the prop only spins in forward and will not stop. Verified proper lower unit oil level and correct 'special' fluid.
Oh, did I mention that the previous owner had installed the terminal cover upside down on the side of the motor which made for an interesting tach installation? (Wasn't me this time honest!)
OK, what have I done now???:redface:
Installed a universal OMC tach. Boat had been rewired so nearly all wires under dash are red. Previous owner had also replaced control box so all wires (except grey) were spliced near control box. The grey wire was cut and just left disconnected inside sheath covering splices. I spliced it and ran it as the SIG wire to the tach. Hooked up remaining wires to tach and fired it up and no tach display. (The tach had been pulled from the dash and a cup holder covered the mounting hole.) Found a green wire that energized when the key switch was turned on so I tapped it for the BAT connection. OOPS! (This doens't work well on a '72 65hp with an electric shift) Moved over to the wire that energizes the choke. Now I have a tach reading with the Forward button pressed.)
Problem is tach seems to work well except around 1K. At around 1K the tach jumps up to 3K without any change in engine speed. If I idle down a little the tach drops to a normal reading.
I thought the tach was supposed to be set on "6". When I hooked it all up there was no reading. I dropped it to the "5" setting and it seems to respond correctly except for the problem around 1K.
A side note is that since I installed the tach the lower unit will not shift. I checked the voltages where the wires drop into the lower unit to the solenoids and they are correct as the different buttons are pressed. And nautrally, the prop only spins in forward and will not stop. Verified proper lower unit oil level and correct 'special' fluid.
Oh, did I mention that the previous owner had installed the terminal cover upside down on the side of the motor which made for an interesting tach installation? (Wasn't me this time honest!)
OK, what have I done now???:redface:
