Adjustable tach, what's right?

[Ridemywideglide]

Boats in the sig. I noticed on the back of the tach there is an "adjustment" screw. When I first got the thing running the tach showed idle to be 2500+/- rpm. This was obviously not the case, but what is the tach supposed to be set at? It appears to have some numbers, 2-4-5-7-12 (there abouts, I can't remember exactly I'll check again this weekend) that are out of sequence. Any ideas?

 

[Bondo]

Re: Adjustable tach, what's right?

Ayuh,... If it said 4-6-8, you'd set it on 8...
I'm just Guessing, but that might be an Outboard tach, which are sometimes #ed by the poles on the stator...

 

[Ridemywideglide]

Re: Adjustable tach, what's right?

Yea if it was that simple I'd have tried that first.. Numbers were like 2 3 4 7 12 or close to that. I'll look again when I can.
If it's by the poles on the stator, where do I find that info??

 

[Don S]

Re: Adjustable tach, what's right?

Yea if it was that simple I'd have tried that first.. Numbers were like 2 3 4 7 12 or close to that. I'll look again when I can.
If it's by the poles on the stator, where do I find that info??

An outboard tach won't work on an IO

 

[Bondo]

Re: Adjustable tach, what's right?

An outboard tach won't work on an IO

Ayuh,... That's what I thought...

'course I still remember the 1st time I saw a tach on a diesel driven by the Alternator,....

 

[Don S]

Re: Adjustable tach, what's right?

Yeah, and then someone changes the alternator and puts a different size pulley on it and wonders why the tach went stupid. Or the belt gets loose and slips.

 

[rodbolt]

Re: Adjustable tach, what's right?

pay no attention to DonS or BonDo.
to old school.
bet they dont even know what an Ipod is.

actually ya gotta pay attention to both, one is good the other very good.
Bondo like the antiques Dons is is like me, stuck.
whats great is both are a wealth of knowledge if you post enough information .
PS, DonS hasnt told me where he is.
my bro inlaw is tracking the ISP.
from apr 09 to apr 20 I will be driving from san francisco to poulsbo WA.
bet I can find him

 

[Don S]

Re: Adjustable tach, what's right?

I'm not too hard to find, I'm in Ocean Shores WA and in the phone book.
I WILL get a PM off to you here in a minuter or 2

 

[Ridemywideglide]

Re: Adjustable tach, what's right?

Here's the back of the tach. Numbers don't add up..

 

[Zackman]

Re: Adjustable tach, what's right?

It looks like it reads pulses per revolution. Have you traced the line to the other end? Are you sure this isn't for an outboard and reading the number of pulses from the stator in the alternator, like Bondo had suggested?​

 

[Ridemywideglide]

Re: Adjustable tach, what's right?

It looks like it reads pulses per revolution. Have you traced the line to the other end? Are you sure this isn't for an outboard and reading the number of pulses from the stator in the alternator, like Bondo had suggested?​

No I've not traced it yet. It's on the "to do" list.
I'm sure of nothing with this boat. I just know it came this way...