Datcon 103643 Speedo calibration?

[Don4107]

Our new to us MCI 5B has this speedometer and no information on it.  At indicated 80 (0-80 dial) actual speed is about 48MPH. 

There is what looks like an adjustment on the bottom that has positions marked A, B, 4, 6, and 8.  It is pointing at 4 now. 

I would try the other positions but I have to pull the steering wheel every time to get to the gauges.

I can't find any info online.  Anyone have one of these?

The complete info from the tag. Can't see the prefixes, model serial ect because of the mounting bracket.

103643             Model?
30L08MIHDB      Serial?
12                   Voltage?
95-27               Date code?

Thanks,
Don 4107, now with a 5B too.

[gus]

80 KPH is about the same as 48 MPH, your spd reads KPH.

If you have an odometer in the spd it will read in Kilometers as well, about 0.6 of a mile.

[Don4107]

More info.  This bus has a Allison 644 and uses a sensor on the trans for speed.

In the manuals that came with the bus there are two instruction sheets but they are both for the tach.  According to the tach instructions, it depends on the model number what the function of each switch position is.  That is why I was hoping someone might have the same model speedo. 

It appears that Datcon has been acquired by another company and they don't have the web site up yet.  Hopefully they will.

Guess I will have to take a ride with the GPS and steering wheel puller and try some of the other positions and hope none of them represent smoke.

Don