Thread:

6-71 Blower ??????

Originally Posted by Dansblown73Nordic

I picked up a couple 6-71 Blowers today. These were from some sort of a flour blower in a Pizza Factory....Im kinda wondering what it will take to rebuild one of these. Its a regular 6-71 Blower. I will post a picture of one of them. Can I just buy seals and gaskets? Id like to run this on my BBC that has a B&M 250 on it now...

no!

Originally Posted by Dansblown73Nordic

well thanks for all the INFO!!!!!!!!!!!!!!! I spoke to BDS today and I showed him a picture of one of them. They are the correct type of a blower. What will it take to run one of these?

Its possible that BDS or the Blower Shop or RBS can set them up if they are in good shape. First off, they were never intended for high rpm operation and the bearing plates front and rear are not up to the boost loads and RPM of a engine. They were never intended to create boost pressure. They will require reinforcing rings around the bearing bores at a minimum, or better yet, new stronger bearing plates. Depends on the boost and RPM your asking for.
The clearances are wrong and need to be reset. The rotors may even need to be trimmed slightly to reduce their diameter. Diesel and "air mover" blowers are usually set up tighter because there is no load or RPM to bend or twist the rotor. The gears may not be up to boost pressures. Depends on the era they were made. Later ones have weaker gears than earlier ones.

You might be able to use the cases, possibly the rotors, if your really lucky, the bearing plates with some modifications. But no, you cannot set them up your self with new bearings and seals. And that was yor original question.

Originally Posted by ol guy

Do your'e self a favor and go back to BDS and ask that question. I have ran 6-71 blowers on a couple or four small big blocks and been nothing but happy! Or you could always run a 14-71 and under drive the hell out of it. JUST ASK THE GUYS THAT KNOW!!! BDS! M

Originally Posted by Dansblown73Nordic

I picked up a couple 6-71 Blowers today. These were from some sort of a flour blower in a Pizza Factory....Im kinda wondering what it will take to rebuild one of these. Its a regular 6-71 Blower. I will post a picture of one of them. Can I just buy seals and gaskets? Id like to run this on my BBC that has a B&M 250 on it now...

Didn't read the question again did you Ol Guy? My response had nothing to do with the SIZE of the blower, it had to do with the questiion he asked. Go ahead, tell him its OK to by bearings and seals and everything will be fine. You've done it hundreds of times

You'll need gears as well as the bearing plates. Most stock 6-71 gears are cast iron and NOT suitable for boost, high rpm or both.

Originally Posted by 058

You'll need gears as well as the bearing plates. Most stock 6-71 gears are cast iron and NOT suitable for boost, high rpm or both.

See, your simply too young Those good ole blowers off the WWII landing craft had steel gears. I know, I have one

But yes, like I said in the post, newer ones are made cheaper and have iron gears. Damn bean counters!

Originally Posted by gn7

See, your simply too young Those good ole blowers off the WWII landing craft had steel gears. I know, I have one

But yes, like I said in the post, newer ones are made cheaper and have iron gears. Damn bean counters!

As I said..."Most 6-71s" most of the forged gear 6-71s are at the bottom of the English Channel.

Originally Posted by 058

As I said..."Most 6-71s" most of the forged gear 6-71s are at the bottom of the English Channel.

, now thats funny! The rest are in France being used as house boats.

Couple of other reasons you can't use it "as is" is because stock GM blowers had a locating ledge down the left side looking from the front, that help locate the blower on the side of the Gimme 6. This rib interferes with most blower manifolds. The blower bolt also, is not symetrical. It has a stagger left to right side. It can only mount on a blower manifold one way. Since this was not a Gimme 6 application, there is no way to know if it is driven from the correct end, or even in the right direction. It may need to have the rotors and drive gears flipped over, or flopped end for end.

Bottom line, you need to have a blower shop determine its feasability for use as a supercharger on an engine.

Originally Posted by Ahsumtoy

How do you know this stuff???

Any time I see some one ask about using a industrial roots for a performance supercharger, alarm bells an sirens go off. Long before GM used the roots blower for the Gimme diesel, it was used for moving air. Primarily for mine shafts. There are way more roots blowers out there being used for things other than Gimme diesels. Like the OP said, his are from some grain mover. Very common use, as are refineries, which is here I see most of them. More and more roots are being replaced with Lysholm screw type(Whipple).

This would be considered a small screw compressor. These things can get down right huge. NO! that is not me!


Then there is always the over grown turbocharger type. We installed these two at the Glen Canyon Dam at Lake Powell. I need to check with Hass or Unchained to find out how much horsepower they think one of these could produce. All these "pressure booosters" we drop on our engines were not originally designed for that. The roots was developed decades before the first internal combustion engine