Homemade 2 groove crank pulley.

[Tony_Urwin]

I own a 1948 Dodge truck with a flathead, which uses a single wide groove pulley. My water pump, 12v alternator, and  A/C compressor have 2-groove pulleys with narrow grooves. Tell me if you think this pulley hack will work out. 

I started by splitting the original single groove pulley.  I used a cut-off wheel and a grinder to remove the forward half of the pulley, then ground the remaining half-pulley smooth.

 

I found an old Mopar pulley with 2 narrow grooves.  I don’t know the original application, but it was only a few mm larger than the original pulley.  I cut off the center section of the pulley with a reciprocating saw. Using a long blade in the saw, I used the outside edges of the pulley to guide the blade.

 

 

I laid the 2-grrove pulley on its back (the cut side), and laid the single groove pulley face-down on top.

 

I used a MIG and alternated spot welds around the perimeter to join the two pulleys.

 

Any opinions?  Do you think it will be balanced enough to power an alternator and an A/C compressor?

 

[JBNeal]

Balance might depend on runout...might be too late to check, but comparing runout of the original pulleys to the modifications could give a baseline comparison... 

[Dave72dt]

It's probably balanced enough.  I'd like to see an additional layer of support for the original pulley in the hub area.  Once you removed the outer original pulley half, what remains is only half as strong as a safeguard against flex and the leverage the new double pulley has from belt tension is increased

[Tooljunkie]

Looks good from here!!

[DJ194950]

I think I would try to get someone with a lath to at least give a spin to check alignment and if possible  a higher rpm spin to check for balance. These engines at most run at about 3K rpm.

Know Anyone?

 

DJ