GMC blower rotation question

The Junkyard down the road just got an old Jimmy bus in for scrap, and it's got a 6-71 Detroit in it. I've heard that in the buses the Detroit's ran backward than a traditional application in a truck or power unit.

My goal would be to pick the blower and eventually convert it for a gas V8.

Can anyone verify the rotation, or if it will be a problem?
I just don't want to buy something that I can't use.

Thanks all!

 

Blowers mount on both left and right sides of the motor,,so yes there were 2 different rotations

Though I think when most folks get blowers they need to have the rotation changed ?? ( could be wrong ) so if you have one already going teh same way,,you may be ahead of the game

triple click on image it blows up huge

 

1. It is a core, not worth a lot, but still worth picking up.
2. No matter what side it mounted on, it is still the wrong rotation for a gas motor.
3. You can flip the rotors side to side to get the correct rotation. other work needs to be done as well.

 

Hell yes get it -then call Rick Dean about converting it -

www.deanblowers.com/6-71_Blower_conversion_How-To.ppt

 

I believe there is a tech thread somewhere on here that covers the rebuild and conversion for a 6-71 blower for gas engines. Yes, you will most likely have to flip the internals, but pay close attention to how everything is put together including the stock rotor clearances and shims used.

I've also seen one or two other places on the net complete with pics. I can't remember the sites. You'll have to do a search for them.

 

Tudor, thanks for posting that. I disagree with a few dubious points, but really a good article.

 

it'll need to be gone through anyway

but to answer your question

rotate the blower drive input clockwise as viewed from the front
the rotors need to turn towards the outside when viewed from the top

 

Most buses had 6V71's, not the best for conversion. Most hot rod manifolds use the straight 6-71.
Any GM blower can be reversed, just pull the guts out and put them in from the other end. The internal gears must be on the drive end.

 

Like Paul says. Air goes in the top. Gets pumped around the outside of the housing intil it reaches the bottom and then out. As long as that is what is happening, good on you.

 

Thanks for the input everyone.
And big props for Tudor for posting the link, that's great tech.