Tach Question

[propless]

Installed a new tach a few weeks ago. Accurate at idle and increases as RPM's are increased but states around 3000 rpm when the motor is past 5000 rpm - where did I screw up on wiring?
Thanks

[Blown 472]

check to make sure it is not on 4 cylinder or something like that. Look at the instructions.

[propless]

It was set properly on 8 cylinder. Any other thoughts out there?
Thanks

[Snorider]

When you say the motor is well past 5000rpm... are you assuming this, or are you verifying with a dwell & rpm meter?
When all else fails, hook a rpm multimeter up to the block and the coil output - that will tell you without a doubt what your motor really is revving to. Then, try hooking that same meter to the back of the tach. If the meter agrees with the tach at that point, i would assume its a wiring problem in the boat.

[82SleekCraft]

You might think that it's accurate at idle but it might not be. Seems that you have a 40% discrepancy. Instead of 5k RPM, you read 3k. At idle, your motor revving at 1000 RPM may read 600 RPM and you might think it's accurate.
Just a thought.