What setting should tachometer be on for mercury 150 Pro XS on 189 trx

[KY Grant]

Got a 2017 189 trx a few weeks ago and last week when trying to get jack plate set right to 3 1/4” we still had to get rpms to 6100-6200 just to get on pad and could only get it to 49 with a 21p . Buddy looked at my tach and saw it was set on 5 and said for Mercury’s it needed to be switched to 6 so that’s what we did tonight and plan on running it tomorrow to see if that helps any just wondering v if anybody else thinks it’s supposed to be on 6 for Mercury’s

[mdtritn21]

What prop are you running? Sounds like it's blowing out.

[Riccochet]

is it a Faria gauge? Should be set to 5 for a 2016 or newer Merc outboard with a 12 pole alternator.

Also, something wrong, a 150 Pro XS shouldn't be turning over 5850 RPM.

[jbtriton80]

I have the multi function Tach/Fuel gauge on my 2017 Patriot. I made a post about it. What I do not understand is a rep from Triton said 1,2,3,4 are all down and 5 is up. This is the back of my gauge, does not make sense?
I am pretty sure mine has never read correctly. It has 2P/4C 3P/6C 4P/8C 5P 6P. Does that mean all 2s, 3s, 4s are down and only 5P is up? What about 6 and 8 ?
Tach.jpg

[Juan Lobo]

So I can't necessarily help your specific question, but my 2019 trx189 with a ProXS 150 will 50 without even thinking about it at about 5200 rpms on a Fury 21P. That is without any jackplate at all. Mine also hops right onto the pad at around 4000 rpms


Ricco I'm curious what you mean it shouldn't turn over 5850 though. Wide open mine will reach all the way to 6300 rpms (about 58 with 500 pounds of fat guys and a full tank of gas).. could it just be the cheap ass gauges misreading RPMs?

[Riccochet]

So I can't necessarily help your specific question, but my 2019 trx189 with a ProXS 150 will 50 without even thinking about it at about 5200 rpms on a Fury 21P. That is without any jackplate at all. Mine also hops right onto the pad at around 4000 rpms


Ricco I'm curious what you mean it shouldn't turn over 5850 though. Wide open mine will reach all the way to 6300 rpms (about 58 with 500 pounds of fat guys and a full tank of gas).. could it just be the cheap ass gauges misreading RPMs?

I assume you're running the new 4 stroke 150 Pro XS. Those will turn higher RPM's. The OP's boat, which I assume is running a 2017 150 Pro XS, is a 2 stroke model. Max RPM's is 5850 for the Pro XS, and 5750 for the Optimax.