McCulloch VS57S Rebuild

[Invectivus]

Because I don’t have enough projects to fail at, I bought a McCulloch VS57S supercharger on eBay. I also bought the repair manual, both are on the way.

Has anyone rebuilt one before? It looks like the rare kind of device that doesn’t need a press to install bearings, is this something that can be done with basic garage tools?

I know that while it’s not the least efficient supercharger, it’s probably close. But I do like the retro goodness.

 

[Frank]

I'm not familiar with that specific unit. I made my living for 8 years with GM 2 cycle diesels asperated with Roots superchargers, so I'll make a couple of points from that experience.
1) The blade clearance between the rotors is specific and critical. Correct rotor bearings is essential.
2) The oil seals in the rotor shafts are also critical, even more so in a throttled draw-thru application where the blower sees high vacuum. Leaking seals or blowing out a seal dumps loads of oil into the intake tract. In a gasoline application this is inconvenient, in a diesel it causes high oil consumption, and a seal blowout, a runaway engine.
Post some pics when the time comes.

 

[aussie7mains]

I'm not familiar with that specific unit. I made my living for 8 years with GM 2 cycle diesels asperated with Roots superchargers, so I'll make a couple of points from that experience.
1) The blade clearance between the rotors is specific and critical. Correct rotor bearings is essential.
2) The oil seals in the rotor shafts are also critical, even more so in a throttled draw-thru application where the blower sees high vacuum. Leaking seals or blowing out a seal dumps loads of oil into the intake tract. In a gasoline application this is inconvenient, in a diesel it causes high oil consumption, and a seal blowout, a runaway engine.
Post some pics when the time comes.

This is a centrifugal compressor with a gearbox in front of it, nothing like a rootes blower. I have a sprintex lysholm type of blower. I would like to change seals, but nobody seems to have any idea of how to do this, any clues/

 

[Invectivus]

If it's the standard twin screw blower, the spare part looks like a standard oil seal. I'd say if you have either the specific model number for the device or the vehicle it originally came off of, looking at the spare parts would tell us a lot. Sprintex seems to make chargers for Dodge/Jeep.

 

[Frank]

This is a centrifugal compressor with a gearbox in front of it, nothing like a rootes blower. I have a sprintex lysholm type of blower. I would like to change seals, but nobody seems to have any idea of how to do this, any clues/

Well. . . guess I proved that I'm not familiar with it! LOL. . . No, I won't speculate on the procedure for seals, already got my foot well up into mouth as is. Especially since GM was so out of the box with much of their 2-cycle diesel engineering, the possibility of the procedure being totally different is high.

 

[funkaholik]

I just googled that model and I agree that the retro look is awesome.

Which vehicle are you planning on putting it on once you've successfully rebuilt it to better-than-new specs? (That's my vote of confidence that you won't fail.)

 

[Invectivus]

I recently bought the May 1960 Hot Rod Magazine as it has three 144 falcon sixes on the cover worked over by Bill Stroppe, and all had the Falcon 145 valve covers. I was chasing a note on the manufacturer (I think it was Bill) but was intrigued by the blown version that had a McColloch supercharger on a 3x1 set of 1904 glass bowl Holly’s.

I have a 250 I want to perk up and put in a future ranchero. Maybe.