Logo
FULL SITE MENU

1971 Johnson 60 tachometer?

A

abcjoyride

Contributing Member
Hello,
Can someone help please.
My tachometer burned out. Do I have to replace with the same tachometer or can I use something generic?
Can anyone suggest a cost effect alternative?
 
If I am not mistaken, that motor was factory wired for a tach that got its signal from the ignition system amplifier. Only saying that because you might have such a tach. However, no fear, it can be modified (simple job) to accept an alternator tach, which gets its signal from the alternator (6 pulses per revolution). Alternator tachs are the norm nowadays. Marineengine has several to choose from.
 
fdrgator said:
If I am not mistaken, that motor was factory wired for a tach that got its signal from the ignition system amplifier. Only saying that because you might have such a tach. However, no fear, it can be modified (simple job) to accept an alternator tach, which gets its signal from the alternator (6 pulses per revolution). Alternator tachs are the norm nowadays. Marineengine has several to choose from.
Click to expand...

Thanks. It was a 2 wire tach. Grey and black wires. Next question, how is the alternator tach wired up?
 
You will find a bunch of yellow wires on the terminal trip on the motor. Some of them are yellow with a grey stripe, some do not have the grey stripe. The ones with a grey stripe connect together, likewise the plain yellow ones connect together. Simply connect your grey tachometer wire along with the yellow/grey stripe wires. Black, of course, is ground. Ignore the grey wire leading to the amplifier (no connection)

Rest of the story: Any new tach will likely also need connection for power and maybe night lights.
 
fdrgator said:
You will find a bunch of yellow wires on the terminal trip on the motor. Some of them are yellow with a grey stripe, some do not have the grey stripe. The ones with a grey stripe connect together, likewise the plain yellow ones connect together. Simply connect your grey tachometer wire along with the yellow/grey stripe wires. Black, of course, is ground. Ignore the grey wire leading to the amplifier (no connection)

Rest of the story: Any new tach will likely also need connection for power and maybe night lights.
Click to expand...

Thanks...that's how it was wired up. Two wire tach. Non adjustable alternator tach. So I can use any tach? Or does it have to be an alternator tach?
 
Alternator tach is the way to go. Simple and plentiful, and they work-----as long as the alternator is working. Are you sure yours is?
 
fdrgator said:
Alternator tach is the way to go. Simple and plentiful, and they work-----as long as the alternator is working. Are you sure yours is?
Click to expand...

There's no alternator. There's a stator, points, rectifier, coil, amp and battery.
The rectifier is working, bench tested and can see charging on battery when motor running.
 
??----The stator is the " alternator " on your motor.----It produces ac voltage that is rectified to DC to be stored in the battery !!!
 
racerone said:
??----The stator is the " alternator " on your motor.----It produces ac voltage that is rectified to DC to be stored in the battery !!!
Click to expand...

In that case the alternator is good. As far as i can tell the rectifier is good.

i have just replaced the amp. I dont have an rpm gauge or a timing light. I have found TDC and followed procedure to set pointer for timing. Do i need to use a timing light or can i set the timing by ear??
 
fdrgator said:
No. It would be better to leave it alone. Unless the last guy set it by ear.
Click to expand...

Worth asking. I've bought a new tach. Just have to procure timing light and most likely one of those new regulated rectifiers. I ran the engine the other day and with increased rpm it was getting to 15 and looked to be increasing and I'm not interested in stuffing my new amp up. Apparently CDI amps don't like over voltage. I guess I'm spending another $100 bucks (60 US)
 
Back
Top