TACHO SETTING

[thommo59]

2018 TRX18 with 200hp Merc Pro XS. Standard Faria brand gauge that comes in the boat. Idle shows around 900 rpm but after that, definitely wrong. Shows 6800 wot, engine has a limiter at 5850. Setting on the back is set to 5, took tach out, moved that switch back and forth in case of bad contact, still same. Faria website only shows up to years 2011 as 12 pole output, switch setting to 5.

Anyone else had this or can suggest a fix other than. “ you may have a bad tach”

thanks

[Savage]

Wouldn't a 2018 boat be under warranty?

[thommo59]

Yes it is however I’m 7,000 miles from the dealer and happy to fix anything I can without always going back to a shop. If this in fact is a faulty tacho, I’ll take all reasonable steps to prove that then talk to the dealer about replacing it

[J Risco]

Yes it is however I’m 7,000 miles from the dealer and happy to fix anything I can without always going back to a shop. If this in fact is a faulty tacho, I’ll take all reasonable steps to prove that then talk to the dealer about replacing it

Sorry, I have no helpful info, just appreciate a guy willing to try to fix something before blaming a manf. and running back to the dealer. Good on ya!

[Savage]

Yes it is however I’m 7,000 miles from the dealer and happy to fix anything I can without always going back to a shop. If this in fact is a faulty tacho, I’ll take all reasonable steps to prove that then talk to the dealer about replacing it

Any Mercury Dealer can plug in a CDS and compare tach readings to the PCM. Your problem could be a wiring issue on the motor side, boat side, or the tach itself. Problems on a new boat/motor need to be documented in case future problems arise for your protection. Good luck.

[thommo59]

[QUOTE=Savage;9114263]Any Mercury Dealer can plug in a CDS and compare tach readings to the PCM. Your problem could be a wiring issue on the motor side, boat side, or the tach itself. Problems on a new boat/motor need to be documented in case future problems arise for your protection. Good luck.[/QUOTE

So can a merc dealer do this as a static test to compare? I heard back from Faria who suggested running at wot and tune the pot in the back of the tacho until it’s accurate. Now I don’t mind a bit of Adrenalin but I can’t see myself pulling out the tacho, extending the harness to reach, driving with my knees at 70 mph whilst holding the tacho in one hand and a screwdriver in the other and guessing that the rpms while I tune it that are now correct. There must be an easier way

[Savage]

A Dealer with a CDS can generate a 3000 RPM Tach test signal to check the accuracy of a tachometer. If you want 100% accurate RPM readings, then you should invest in a Smartcraft instrument. Most standard tachometers are notoriously incorrect.