Power Gen on a 21 stud

Ken/Alabama

Ken/Alabama

Well-known member
Working on a customers 34. It has a 21 stud flathead and he’s going 12 volts and supplied a Power Gen alternator that looks like a generator. Problem is that the pulley on the Power Gen doesn’t line up with the other pulleys. Put the original generator on and it lines up perfectly. They advertise 32-48 to be the same but what I’m finding out that’s not true by measuring original generators against the Power Gen. Has anyone experienced this before. ?
 

Attachments

  • IMG_9553.jpg
    IMG_9553.jpg
    43.3 KB · Views: 92
  • IMG_9554.jpg
    IMG_9554.jpg
    52.6 KB · Views: 93
I added a spacer to the Gen mount.
It's just about a 1/4''.
It moved the Powergen enough for the belt to line up.
 
Does the fan mount on that powergen? I thought the powergen used radial bearings, not angular contact bearings to handle fan thrust.
 
ndnchf said:
Does the fan mount on that powergen? I thought the powergen used radial bearings, not angular contact bearings to handle fan thrust.
Click to expand...

I have the pulley to mount the fan to the Power Gen. I don’t particularly like the idea but he has other cars with the same setup and that’s what he wants. That’s a lot of thrust on that front bearing for sure.
 
I have had other folks tell me they run a fan on a power gen with no issues and thousands of miles. Not to say it would never cause a problem. I have not tried it....yet.
 
A conversion from EJ Whitney is a better choice IMHO, but...they are expensive, there's a wait time, and its not what the customer wants
 
Yes, I added 2 small 1/4" aluminum strips to the front fork of the Powergen.
I used 2 countersunk fine thread screws on each strip.
The strips move the unit out and also keep it aligned on the Intake.
I have another Powergen on an 8BA in my roadster and that has a fan mounted to it. I used a Speedway fan mount pulley. 3600 miles on it with no issues.
I believe Powergen is working on a more robust unit that they will be OK with if you use a pulley mounted fan. Right now, they do not recommend it.
 
I have used a powergen with the offenhauser fan mounted pulley with zero issues. On my cars the offy pulley lines up the belt well. 12K Miles on my 36 pickup this way all while swinging a factory fan from it and no issues. Puts out a solid 60amps I have one EJ Whitney unit and while nice puts out less than half the amperage and it's a small backlogged company. If I have a issue with my powergen I can have a replacement in 2 days, EJ whitney 3-6 months and double the cost.
 
You can run into the same sort of mis-alignment using Ford generators from various years. Put a spacer between the intake and the generator.

cas3 said:
A conversion from EJ Whitney is a better choice IMHO, but...they are expensive, there's a wait time, and its not what the customer wants
Click to expand...

As of last summer Tom Whitney had stopped taking orders for conversions due to health issues.
 
I run my power gen on my 36 roadster using the offy fan mount that fits on the power gen. Everything lines up perfectly and have zero issues and it’s a 21 stud
 

Attachments

  • ISIMG-817919.jpg
    ISIMG-817919.jpg
    53.2 KB · Views: 188
petehoovie said:
562065
Click to expand...

The 21 stud I’m working on is a 37 with the early heads and water pumps . The pumps line up with the crank pulley and the original generator lines up. I have the pulley that accommodates the fan on the powergen but it’s not lined up with the other pulleys. Could it be a difference in intakes ?
 
Could you perhaps add a spacer to the back of the pulley, by welding a 1/4" or so coupling piece to add shaft support. Then you might be able to space the pulley out on the shaft that 1/4", Maybe?

Al Hook
 
35fordtn said:
I have used a powergen with the offenhauser fan mounted pulley with zero issues. On my cars the offy pulley lines up the belt well. 12K Miles on my 36 pickup this way all while swinging a factory fan from it and no issues. Puts out a solid 60amps I have one EJ Whitney unit and while nice puts out less than half the amperage and it's a small backlogged company. If I have a issue with my powergen I can have a replacement in 2 days, EJ whitney 3-6 months and double the cost.
Click to expand...

Does the Offenhauser fan pulley have a keyway? Or just draw it up tight to the bearing?
 
You must log in or register to reply here.
Back
Top