bugelingkayaker
Seaman Apprentice
- Joined
- Nov 13, 2019
- Messages
- 49
well im in the home stretch now with my boat project. but i need some help with the tach and speedo.
good news from anyone who read my other post is i didnt destroy anything when i ran it without the hose for a minute like a dumbass.
anyways some other stuff i did- i was having intermittent problems where turning the key did nothing. as i suspected, it was nothing wrong with the engine, the wiring inside for the key switch and choke button were shot. with how little was left of those wires im amazed that lasted as long as they did. i didn't want to buy an all new wiring harness for close to $200, so instead i cut the old wires as close to the plug as i could (i wanted to save the plug because it still looked to be in great condition) and i picked up some marine grade wire and reattached to the switches, and inline soldered them in to the old wires, did some heat shrink and then some electrical tape for good measure. im gonna pick up some extra tubing to cover them further to protect from the elements. unfortunately i was unable to find exact wire colors to match so my brown wire is now green, among a few other changes (which i documented so i dont confuse myself later). well the new wiring is working great, engine starting right up without issues. the tach connector plug in the control box was shot as well and beyond salvage, so instead of trying to replace it i just ran the wires that would have connected to it straight out the front of the controls through the hole where the plug would have been.
next i picked up an aftermarket tach from a mercury specialist in my area who assured me it would work for my 1973 850 thunderbolt. i wired it up as instructed but with the engine running its not doing anything. the little lightbulb turns on but thats about it. i've seen some conflicting info on number of poles, some sources said 6 some said 4, so i've tried it with both, but no success either way. i'm not too clear on how exactly a tach works, but is this not working a symptom of another electrical component not working? is it possible just a bad connection somewhere? i thought wiring it up was pretty straight forward, did i screw it up somehow...?any tips or advice hugely appreciated
next is the speedo. i traced from the speedo a tube that comes off it and goes down towards my engine and... is just lying there in the bottom of my boat not attached to anything. i also can't for the life of me figure out where it even would attach. i've poured through my parts catalog for the motor and cant find anything speedometer related. i have however found the little hole on the front of the lower unit that i've read is supposed to be the water inlet for the speedo. any info on what i should be looking for to hook it up?
again thanks for any info. i apologize a few of my other posts i got super helpful responses that solved the problem and i never went back to my post to thank those individuals who helped me, so if any of those people are reading now, thank you!!
good news from anyone who read my other post is i didnt destroy anything when i ran it without the hose for a minute like a dumbass.
anyways some other stuff i did- i was having intermittent problems where turning the key did nothing. as i suspected, it was nothing wrong with the engine, the wiring inside for the key switch and choke button were shot. with how little was left of those wires im amazed that lasted as long as they did. i didn't want to buy an all new wiring harness for close to $200, so instead i cut the old wires as close to the plug as i could (i wanted to save the plug because it still looked to be in great condition) and i picked up some marine grade wire and reattached to the switches, and inline soldered them in to the old wires, did some heat shrink and then some electrical tape for good measure. im gonna pick up some extra tubing to cover them further to protect from the elements. unfortunately i was unable to find exact wire colors to match so my brown wire is now green, among a few other changes (which i documented so i dont confuse myself later). well the new wiring is working great, engine starting right up without issues. the tach connector plug in the control box was shot as well and beyond salvage, so instead of trying to replace it i just ran the wires that would have connected to it straight out the front of the controls through the hole where the plug would have been.
next i picked up an aftermarket tach from a mercury specialist in my area who assured me it would work for my 1973 850 thunderbolt. i wired it up as instructed but with the engine running its not doing anything. the little lightbulb turns on but thats about it. i've seen some conflicting info on number of poles, some sources said 6 some said 4, so i've tried it with both, but no success either way. i'm not too clear on how exactly a tach works, but is this not working a symptom of another electrical component not working? is it possible just a bad connection somewhere? i thought wiring it up was pretty straight forward, did i screw it up somehow...?any tips or advice hugely appreciated
next is the speedo. i traced from the speedo a tube that comes off it and goes down towards my engine and... is just lying there in the bottom of my boat not attached to anything. i also can't for the life of me figure out where it even would attach. i've poured through my parts catalog for the motor and cant find anything speedometer related. i have however found the little hole on the front of the lower unit that i've read is supposed to be the water inlet for the speedo. any info on what i should be looking for to hook it up?
again thanks for any info. i apologize a few of my other posts i got super helpful responses that solved the problem and i never went back to my post to thank those individuals who helped me, so if any of those people are reading now, thank you!!
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