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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Dreamscape on November 29, 2010, 05:46:03 PM

Title: Looking for Tachometer Sending Unit for 8V71
Post by: Dreamscape on November 29, 2010, 05:46:03 PM
Does anyone have or know where I can get an SG sending unit for a Dixson 3,000 rpm tach? I'm having a hard time finding anything online. I'll give Precision Speed a call if all else fails.

Thanks Group!

Title: Re: Looking for Tachometer Sending Unit for 8V71
Post by: Tony LEE on November 29, 2010, 06:12:57 PM
Will it work off the 1/2 wave rectified alternator output assuming your alternator has one
Title: Re: Looking for Tachometer Sending Unit for 8V71
Post by: Dreamscape on November 29, 2010, 06:48:33 PM
No, this particular unit says it must be used with an SG201A. I have another tach, 4,000 rpm, hooked up to the alt and it's not as accurate as I want.
Title: Re: Looking for Tachometer Sending Unit for 8V71
Post by: txjeff on November 30, 2010, 05:07:44 AM
Paul,

I got my tach from Precision Speed, they were very helpful and priced right. Give them a call.

jeff
Title: Re: Looking for Tachometer Sending Unit for 8V71
Post by: TomC on November 30, 2010, 08:32:31 AM
Not all, but many 8V-71's have a tach drive off the back of the blower.  I used a Isspro Tach and used the tach drive to run the synchronous generator for the tach.  It works very well.  Good Luck, TomC
Title: Re: Looking for Tachometer Sending Unit for 8V71
Post by: bevans6 on November 30, 2010, 09:06:17 AM
My 8V71 has a tach drive on the front cover beside the water pump, driven by the LH cam.  Isn't the tach drive from the blower going to be off a little bit, it the blower drive is 1.95:1 instead of 2:1?

I found something that says that a SG201A delivers two pulses per revolution, in case that helps.

Brian
Title: Re: Looking for Tachometer Sending Unit for 8V71
Post by: luvrbus on November 30, 2010, 12:28:53 PM
Paul, call Doyle and get the part number from him for tach drive for the front of the engine that is the easiest place for you to hook up he bought his from Smiths DD in Salt Lake



good luck
Title: Re: Looking for Tachometer Sending Unit for 8V71
Post by: Dreamscape on November 30, 2010, 01:10:34 PM
Clifford, I'll give Doyle a call, Thanks!


Thanks for the input everyone! :)