Supercharger rebuilding facts/probs/pics :(

suutari

Registered User
>>the special seals that are located in the cartridge behind the bearings, where the rotor shafts would enter the case<<
These appear to be a special part that prevent the flow of supercharger fluid from the cartridge into the case, as well as the flow of compressed charge air (boost) from the case into the cartridge.<<

Hi!
If someone knows what type of seals these are and can inform me that would be nice?(saw one thread that said they would be neoprene? seals?) I just took teh first rotor/gear apart and found out that it´s pretty press fit..(have to warm the gear when putting it together too)What is the best way to get the rotor clearances right when putting it together and how to do it..since the splines in the rotor shaft are just tiny ones that have been used to get it tight at first plase..not to align the shaft? I can put it together but it´s better if someone could give me some advise..since I live far away from any rebuilding service facility. I will take some pictures tomorrow and post them here so everyone can see them. The bearings are cased too as some of you might know but that should not be the problem...(I´ll take them apart tomorrow)If right size seals can not be found I think it´s fairly easy to lathe the rotor shaft(21.80mm) and bearing seat to proper dimensions for differend seal with better availibility...
I hope someone with knowledge of this would inform me A.S.A.P. so we could save one SC again :). Mine was leaking oil to intake
and the nose seal was gone too..but rotors are fine as everything else too..
+any other clearance/blueprint info of the supercharger is welcome..what is the minimium clearance between case and rotors that it would still work as it should with normal RPM range.

I have searched all the threads and found no other info of the rotor/gear thingie or proper clearances So if you know something please share your aknowledge. I´m willing to share mine after this rebuild..we get out of this mystic rebuild ones and for all. Sorry if it takes someone out of business tho..but how many has press of their own...really. So the loss of customers is probably not an issue here. It will reguire special tools always.

Cheers, Sami from Finland
 
Im getting ready to rebuild mine also. I dont pay anyone to work on my stuff anyway so no loss to them.
 
supercharger seals

After long hours of research, I've found that these seals aren't commercially available.
You've probably found that Magnum
wants you to send the unit in for refurb and to charge you
big $$...sorry but that's the way they play this game!
You can have them fabricated by a custom seal maker but plan
on spending about 1000 bucks for them to tool up and then
make you 2 seals! If you haven't noticed they are different sizes!
sooo...that means 2 different sets of tooling...these seals are
unique, the shaft diameter is not common, so you can't just buy
any old grease seal and install. The temp rating is of concern, as
it the design! The solution I've come up with
is to make my own, yes, I KNOW this is crazy, but this is what
I'm going to do....I've already got the lathe and a couple prototypes started.
If I'm successful (and I don't see why I won't be) If you want a set, I'm sure we can work something out!
Meantime, If you find a better solution, Id be curious to find out
what that is! This whole scenario has been a HUGE source of
frustration, and the 'powers that be' at the manufacturer sure
have a captive audience on this market!
By the way the rotor
clearances are around .004"
Cheers,
Bill
 
thanks for the info so far :)...Yep..that´s the way things go now days. But I will search alternative seal near the same dimensions(if the outside dimension is the same that is good..I still have the other rotor shaft in cartridge..) The rotor shafts can be lathed down to 21mm at least without any concern about strenght..since the bearing part of the shaft is as low as 17mm( and some where around even lower acting as a fuse). Gears can be locked back together and clearances met by using something between the rotors during installation. Taking in grand of the slack between the gears..hmm..maybe there is our answer ;). Plus the sealing base can be opened up a little. Just have to search some gatalogs for two way pressure seals for high temps..even using bearings with two/one way pressure shields
might work as part of the solution (should be okay at least keeping the oil out of the rotor side ;) )..since I have acces to a whole machine shop and I´m doing mechanical engineering major that should not be a problem. I will too keep everybody updated about this thing. Looking into porting and coating the rotors as well during this rebuild process..Hope we find a way to sort out these problems ;)

More info welcome..nice to hear what others have allready done so we get this sorted as quickly as possible.

cheers, Sami
 
I thought Wynne Carter "Tbird88" sold rebuild kits for the M90's...You may wana ask him about it...He is VERY busy right now so it may take awhile for him to get back to you...I believe that Ryan Harris is knowledgable on this as well...

Brad
 
seals

FYI,
Wynn, otherwise known as tbird88, does sell kits.
These are for rebuilding the snout not the rotor pack,
unfortunately. He's also sells and engineers other cool
stuff...like poly bushings for the rear differential...
one other thing, before you go machining on those
shafts, you might want to verify that they aren't surfaced
hardened at the seal journal.
Cheers,
Bill from TX
 
You have good point there :)...I don´t want to screw that up if not necessary. it might be possible to coat it with nitrate etc. after machining tho. Seems the shaft size at seals is 21.85mm quite close to 22mm. Other seal has dimensions 21.85x33.41x7mm and other is 21.85x34.95x7 just quick measurements..If I can find something for that saft size the outer diameter can be machined to at least 35-36mm(other one is allready 35) or spacer made to down size the hole. Seal can be as much as 10mm deep too. Other thing is how to lock up the bearings again because the lip that holds them in place does in fact take care of the rotor axial movement. Bearings are standard size 6203. Originals are made by NSK and they are special type that have marking X28 at inner ring. Maybe C3 clearance would be okay ;). They have somekind of plastic strips at outer ring and it has something to do with shattering or preventing movement/wear in the bearings/bearing cases. Have to check if someone knows exactly why it has the stripes.There isn´t much room to make anything to bearing cases (threads/lock groove). High temperatures are not that good for clueing the bearings eather so I might do lock rings for the bearings that bolt up with small bolts to the case. This thing is really interesting ;)..heh. they did not intend it to be dismantled for sure. Also I´m thinking other bearing alternatives too with high rpm range..Gears should be fairly easy to fit back tho with heating/freezing the parts :). I´ll post some pictures today when I get home. No matter what I have to change, it is going to be running again ;)....and hopefully ported and with better performance too. Tho´ I wouldn´t try to do this with hammer in the garage :rolleyes: The snout is peace of cake compared to this baby...

PS: the end bearings on the case are INA FC65477 if someone is interested on those...You can with other bearings there too with the same size if the rpm and heat ratings go hand in hand...and the cartridge bearings were not hard to remove at all..and you don´t need to machine the lip away. Just press them out and it takes only 500kg or so to pop em´out...;). The lip is gone, but there is no way to save it if you wan´t to change the cartridge bearings..
 
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The Magnum Powers rebuild does not include the bearings and seal in the rotor cartridge. From what I understand, the only place those bearings are available is Magnuson the Eaton distributor and they won't sell them.

To fix my leaking seals I just bought a low mileage used rotor cartridge from a late model SC blower that had a little teflon flaking off for around $100. I would suggest you consider doing the same.

David
 
I think they chance the rotor cartridge as whole if necessary?..but since I´m doing a lot of other stuff too for the blower and have acces to necessary tooling..Why not. Plus I have time too. Easyer would be to buy new one. This one Will be rebuildable when I finish it and the same time I´m learning new things. By no other means it is not the way to go if it weren´t just for fun..:rolleyes:
 
supercharger parts

I have researched the bearings and have sourced them, all
I need is the cash!!! All this info is at home, so when I can
I'll post the list on this thread....can't remember all the specifics
off the top of my head..lol...they're aircraft turbine grade,
spec 5 rating...I'd planned on using loctite, the strongest stuff I
can find, to lock the bearings in place. When I disassembled
the press seemed to work quite well, and I match marked
everything before going nuts...
but I'm there with you on learning and
having fun rebuilding. Not the cheapest way to go
but at least it will be done the way YOU want!!
Getting a used blower is wise, especially if you want
to drive the car while working on the other.
gotta go...
Bill
 
What about making a billet rotor pack plate to fit bearings and seals that you can get with the right ID sizes but maybe there OD's are either larger or smaller than the Eaton pieces?
 
Rotor Bearings are available. Tbird88 (wynn) has them available but you can find them yourself as well.

bearings0065.jpg


http://www.datarecall.net/~tbird88/index/parts/4sale1.htm
 
Those are the rear rotor needle bearings which are easy to get Mike. The problem as has been said is finding bearings and seals that go into the front of the rotor pack in the rotor pack plate.
 
I just looked into it and it would be very easy to make new cartridge from billet with CNC..not too hard, but before that I all ready sourced some seals (ptfe,viton etc.) That are maybe enough close and can take the challence..and by the way inch sizes for original seals are
axle shaft: 55/64
outside blue: 1"5/16
outside red: 1"3/8
deph: 17/64 (this can be larger too..)

Do a ww.Google.com search with high performance seals..dual lip,viton etc..
American high performance seals should have some..just like the originals. They had their E-mail full so could not ask about them today :(

As for the bearings..you won´t probably need that good bearings..bearings that are rated beyond 14 000rpm are not too expensive and come in standard case( maybe 5-7$ each). I found some that are rated to 22 000 and so on...price is not concern of these. How expensive are the original bearings? are they exactly
the same ones :)?

Using the strongest bearing clue with high temp ratings is what I´m going to use probably too when I have time to ask around the specs...or then make the locker rings that will bolt on with small screws to the support pilars(have to calculate some stuff before this ;)...)

Happy to see someone else has the same project ;)..nice!
Cheers, Sami
 
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Sami thanks for posting this info it could'nt have come at a better time. I was getting ready to tear my rotor pack apart and try to figure it out myself but the info you are providing has now put me ahead of the game. THANKS!:) :cool:
 
rotor plate fab?

are ya'll actually proposing that
machining the rotor plate is easier than fabricating
the seals? If you could explain a little further I'd
appreciate it!
when considering bearing choice
please note that they should be spec 5 and
you need them to handle at least 400 degrees F
and they need to be temp rated.
I think the goal here is to end up with an upgraded rotor pack,
not something thrown together...
Make sure the seal design is the same, if you install a seal with
a different design, this could spell trouble.
A non-pressurized single lip grease seal won't work properly.
There is also the issue of two different sizes for these seals...
any guesses to why they designed it this way??
My guess is that it has something to do with the harmonics
generated when those baby's are spinning at 14K+ and there
could be a fundamental frequency that vibrates and
eventually cracks that rotor plate! High frequency stress is
powerful stuff, (opera singer shattering the glass)...
just my two cents.
cheers,
bill
 
http://www.seals.saint-gobain.com/media/documents/S0000000000000001018/OmniLip Catalog_Seals_app.pdf

What do you think about these dual lip ptfe seals?(haven´t converted that speed to m/s still so.. ;))
I don´t really believe that the reason for different size hole would be harmonics..they are in differend phase after all and should be balanced pretty good + It´s not that heavily engineered unit it would have been easyer to make it more robust and use different size/style bearings I think...I´m just building it for my self and someone can do it other wise if they want to..but why the heck put some top end stuff there that will last forever and cost heck of a lot more than stuff that does the same job for fraction of the cost? Then I probably should do the case from titanium and design my own rotors etc. from carbonfibre and so on..I just want the seals to hold and the thing to work like it should. Plus I´m not going to spin it above 15 000rpm:s ;)...

Question about machining new rotor plate might get answers when you look at the pictures..it would be pretty easy to draw pictures and machine it from solid block with CNC machine since there are not that many functional measurements that are important. I can even acces to computer measurement device so it really is not that hard to blue print the old peace and draw new one that is even more robust with Ideas/CAD/katya/Solid works etc ;).

If you have any succestions about seals etc. all are welcome :). If I find the original bearings and they are not something like 200$ per piece I´m using them for sure..if some bearings that are rated the same rpm range and heat resistance values but are 10$ piece I´m going to use them...
 
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