DD Flywheel question

[DaveNCari]

I am installing a tach on my 4104...

Stewart-Warner has a table in their instructions that says "ALL DD" 118 Teeth

Can anyone confirm that the 671 has 118 teeth on its flywheel?

That simply strikes  me as odd...that EVERYTHING powered by Detroit Diesel has the same number of teeth on their flywheels....especially in the pre-electronics days when there would have been no reason do do so.....

Dave

[luvrbus]

You are miss reading the instructions there are several different flywheels the sae 1 bell housing and 19 inch flywheel have 118 teeth a 17 inch will have less teeth with the SAE 2 bell housing same deal with a 92 series or a 53 series  

good luck

[Utahclaimjumper]

You also should be able to drive your tach from the front pulley or the generator/alternator.>>>Dan

[DaveNCari]

OK...I am obviously new to this "big engine" stuff...so how do I tell if I have the SAE1 or SAE2 bell housing??

My 4104 has its original drivetrain...the 671 and the Spicer 4spd...

If I take a pic of the engine/trans...can a knowing eye simply see the difference?

Dave

[luvrbus]

I take it you are using a transducer/magnetic sensor that screws into the plug hole in the bottom or the side of the bell housing ?

[DaveNCari]

Indeed.....



DG

[TomC]

Most of the 2 stroke engines have a built in tach drive coming off the blower somewhere.  On my 8V-71 it was on the end of the blower. I bought the synchronous generator and powered my tach off that.  My tach is an Isspro with engine hour meter.  Good Luck, TomC