meaning of tach settings on back

[1*jaybird]

I am going to use a tach from a friend. he never used it and it came with his motor. want to check my idle speeds and running speeds/rpms. there is a dial on the back that goes from 1 (I believe), all the way up to 6. is this for the number of cylinders of the motor? thanks for any help.

 

[Barnacle_Bill]

Re: meaning of tach settings on back

No, it isn't he no of cylinders. It is the no of pulses coming from your stator. Since you posted this in the johnyrude section, I assume you have an evinrude or johnson. Most of them are 6 pulses. BTW, automotive tachs will not work.

 

[Silvertip]

Re: meaning of tach settings on back

Some tachs are marked for the # of cylinders, 2 & 4 stroke, and number of alternator poles. Since you did not tell us what engine you will use this on, we can't help you beyond this.

 

[1*jaybird]

Re: meaning of tach settings on back

it is supposed to be an outboard not automotive type tach. my motor is a 1977 75 hp three cylinder. I can get the model number and post back. with this info, is it 6 pulses? I never knew that so would it say in the manual on how many pulses it has. thanks for the help.

 

[1*jaybird]

Re: meaning of tach settings on back

My model number is 75743s. Hope this helps and thank you for replies.

 

[1*jaybird]

Re: meaning of tach settings on back

ttt

 

[farginicehole]

Re: meaning of tach settings on back

Is it a Teleflex brand tach? If so, I think I have some literature out in my barn that might tell you what setting to use.

 

[Mark42]

Re: meaning of tach settings on back

I know that Teleflex brand has a list of o/b's and their tach settings on their website, you'll have to do some browsing. If not teleflex try o the tach manufactures web site. They usually have the info you're looking for.<br /><br />BUT, I know from experience that the Teleflex motor/settings info is wrong for my motor. So it is important to get the stator info from your service/repair manual for your specific model and compare that to the settings that the tach manufacturer specifies. In my case the 40hp Evinrude came with two completely different ignition systems, a 4 amp recifier system and a 12 amp alternator system. The tach settings are different for the two systems. I guess that Teleflex just list the most popular model engines in their list without making any updates over time.<br /><br />Check and double check if you want the tach to be accurate.

 

[1*jaybird]

Re: meaning of tach settings on back

I cannot find a namebrand on it anywhere, however on the back is a molded raised scrolled letter "M". it is about four inches round, didnt measure it. it is orange in color. I cannot seem to find anywhere in the service manual on the stator for info on pulses. I am totally lost on this . would there be one pulse for each cylinder and with mine there is three cylinder, hence setting of three? I will check to see if I can find anything searching the web on this particular tach. thanks.

 

[1*jaybird]

Re: meaning of tach settings on back

just found two on ebay past auctions that match up with mine. omc /evinrude 7000 rpm tach. so now with this info and previous post info, can somoeone please help me on settings. thank you.

 

[1*jaybird]

Re: meaning of tach settings on back

ttt

 

[MarkHPCA]

Re: meaning of tach settings on back

As said before the number from 1-6 represents the number of pulses from the stator. A stator will give out a pulse for each pair of poles so for 6 pulses you would have a 12 pole stator. The Teleflex site list both 10 and 12 pole for your motor. Check you manual it should spec the number of poles......anyone out there know the answer?