inductive tach how good

[RICKRICK1]

I have a 1967 65hp mercury and am adding a inductive tach I got from the merc dealer. It shows 4 number places but seems to read only the first three starting from the left. ***0 Is this correct or do I need a new one? Have seen a posting on this before but could not find it with search. Thanks in advance for any help.

 

[FlyBoyMark]

Re: inductive tach how good

Are you talking about the Mercury Service Monitor about the size of a match box?

 

[RICKRICK1]

Re: inductive tach how good

Yes

 

[FlyBoyMark]

Re: inductive tach how good

If the lead is only 6' long, you use 1 to 3 wraps around the # 1 cylinder plug wire on newer engines. The older engines could require up to 5-7 wraps to work because older ignition systems don't have the same high tension voltage as newer outboards. If you extended the main sheilded wire, it must be done very carefully with EXACTLY the same tiny sheilded wire with a tiny sheilded connector. You cannot extend the wire that is soldered beyond the shielding. In addition, if you extended the wire, you will need to make at least 6-7 wraps to make it work. Mercury makes 3 models of these "Service Monitors" and you must make sure you have the rite one for your motor.(They are actually made by "Tiny Tach" for Mercury's specific neeeds)<br /> I use one of these on my new Merc 40 HP "micro bass boat" and had to make the cable longer and the other aforementioned mods to make it work. If you need more info let me know and I will point you to the proper places to obtain the wire and connectors for an extension.<br /> The little tach works fine and updates fairly fast....I have no complaints....Reads hours when the engine is off

 

[Lark40]

Re: inductive tach how good

I have a TinyTach on my 1960 Evinrude Lark 40.<br /><br />It works great. But, when ordering, the TinyTach technician told me to wrap both the upper and lower plug wires because my engine has two sets of points.<br /><br />Don't know zip about your engine, but though I'd share that info in case it could also apply to you.

 

[RICKRICK1]

Re: inductive tach how good

Thanks for the replies. Flyboymark please forward the info on where to get cable and connector. I think mine is not workiong right as my dealer told me that I coulkd extend it by using any sheilded wire. Mine reads on the first three digets starting from the left, reverse of how it should I think. Hpefully its just a cable problem. Again thanks for the repies.

 

[FlyBoyMark]

Re: inductive tach how good

Outfit is called "Skycraft Parts" surplus parts in Orlando, Florida. (407) 628-5634 or They do mail order and credit cards or debit cards.www.skycraftsurplus.com<br />You need two Omni Spectra 2001-7188-00 micro sheilded cable connectors (male) and one matching double female coupler. They are TINY!!! So make sure you know what your doing when you assemble them to the wire!!!! There are four different lengths that you cut the casing, sheilding, inner insulator and conductor which must be soldered to the center pin BEFORE assembly.... I honestly dont remember the spec on the wire, it's not marked on the surplus cable I have. Call "Tiny Tach" and they will tell you....

 

[FlyBoyMark]

Re: inductive tach how good

Didja' try more wraps yet? The three digits are the clock only, your not getting signal yet, Make sure the other "ground lead" is grounded to the engine block.....