Tach for Merc 500

[00scoots]

I just bought a completely rebuilt 1972 Merc 500.<br />I'd like to install a tach so that I can monitor my rpm's. I've found several different tachs ranging from 6000 to 8000 rpm's.<br />What's the suggested max rpm for this Merc 500?

 

[mellowyellow]

Re: Tach for Merc 500

5K to 5.5Krpm is what I would shoot for.<br />good luck,<br />M.Y.

 

[00scoots]

Re: Tach for Merc 500

Thanks for your reply, mellowyellow.<br /><br />One more question for you "merc techies".<br /><br />When I bought my Merc 500 (it's going on the boat next week), I told the salesman that I had a 55hp Homelite on the boat and I had a new tach and ammeter put on the boat 2 years ago when I bought the Homelite. <br /><br />The salesman said the tach would not work with the Merc, because it was for a 4 cycle outboard (no one looked at the tach, an Equus Pro Tach) and the ammeter won't work, because there's no charging system .<br /><br />I've read quite a few posts on this forum regarding tachs for Mercs (You guys have been a wealth of information!!!). I crawled under the dash of my boat to look at the back of my tach. There's a 3 position switch on the back for 4 (current setting), 6 and 12 (or was it 10 - I forget). <br /><br />Will switching the tach to the 6 position work for a Merc 500? <br /><br />Thanks for your information.

 

[wileecoyote985]

Re: Tach for Merc 500

Can't answer your question about your current tach. If it won't work, you might want to try a tiny tach. Just do a search and you'll find a link to them listed in this forum.<br /><br />wile e

 

[gaugeguy]

Re: Tach for Merc 500

Best I can do for you is a "maybe", and it's not gonna hurt anything to try it.

 

[Trent]

Re: Tach for Merc 500

Its possible? Whats your serial number. If I remember right a few of those had alternators and not rectifiers. If it has a alternator your tach will work. If it does it need to be set to 12p.