tach adjustment help

[1badhusky]

So, my tach is reading over 6k rpms - i know it's not turning that fast though - it's a 2007 4.3 mpi - anyone know if you can adjust this yourself and how, or do I need to take it in?

 

[Bifflefan]

Re: tach adjustment help

So, my tach is reading over 6k rpms - i know it's not turning that fast though - it's a 2007 4.3 mpi - anyone know if you can adjust this yourself and how, or do I need to take it in?

I dont know any adjustment on any electric tach's. hook up another one and then compare results. then you'll know if there is a problem.

 

[Barnacle_Bill]

Re: tach adjustment help

Look on the back of the tach and see if there are any adjustments. Let us know what they are if any.

 

[gcboat]

Re: tach adjustment help

A quick check of your tach will require you to know how many poles your alternator has - whatever that number is you need to divide that by half.
So,if a six pole alternator you will use the #3 position, etc. on the back of your tach. As bhile mentioned there may not be any settings so it could be something as simple as a loose or corroded connection.

 

[1badhusky]

Re: tach adjustment help

hmmm...ok, not sure about the alternator poles - perhaps I should let the experts handle this. I couldn't even figure out how to change the oil - not exactly a great wrench here.

 

[Barnacle_Bill]

Re: tach adjustment help

I think this is an I/O in which case the no. of poles does not apply. You would just set the tach for the number of cylinders.

 

[NYBo]

Re: tach adjustment help

I think this is an I/O in which case the no. of poles does not apply. You would just set the tach for the number of cylinders.

Yep. Number of poles on the alternator only applies to outboards, AFAIK. Maybe some old, oddball I/Os too.

 

[1badhusky]

Re: tach adjustment help

thanks everyone...will check this out this weekend.