Rotor pack/gear plate swap how to...

super red91 said:
The new rotors dont have the cast around the gears, dont know why but they just dont. Nothing to worry about.


The one alignment pin needs to be moved into the lower position. Use a vice and a socket that is about the same size as the pin and put a larger socket on the other side to press is out. Clean out the new hole and put some oil in it so when you press in the pin it goes in smooth.

We just finished putting my friends back together took pictures along the way, but the digital camera took a ~~~~ so we had to use a phone. Dont know how good the pics will come out but it should help.

I did some porting on the blower inlet/outlet (94/95 style) added the coated rotors and it makes a tad over 15psi with a STOCK pulley. The car (89 sc) has an intake, 75mm tb, ported/welded plenum, raised top, double ic, and a full exhaust.

Hey that's a great idea. I'll do it tonight and post my results for those interested. Looks like I'll have to find a socket whose OD is roughly 0.413" ;)
 
power steering pump swap

thinking about tackling my p/s swap .looks like im going to need to take off most of the front of the motor? any short cuts ? let me know thanks
 
Update

Okay, here's the scoop. I got the rotor packs swapped and everything fits real nicely and is torqued to 25ft lbs. I have one question, there is a little play in the pulley. It seems to move about 3-5 degrees before the one pin in the gear engages the bent end of the coupler's spring. I am assuming there is only one way the spring will go in and allow everything to bolt together? I ask b/c the damn spring fell out when I removed the snout before I saw how it sits in the coupler. I'm hoping that what seems like an unreasonable amount of play is just the fact that there currently is no oil in the SC. (I'm letting it dry overnight with the top off and the fill plug out.) Can someone confirm this or do I have to remove the snout and reposition something? Thanks for the help today guys! :)
 
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Since i cannot see how you installed the spring,there is a method to check.Hold the rotor pack blades by the exit port of the blower.Then with your other hand turn the pulley clockwise,you should feel the resistance of the spring.It should turn about an inch or so then engage solidly against the rotors,but you must feel the spring tension.Like it would turn back itself.Check it out.;)
 
Here's a pic to help with my previous question. I wasn't sure on which side of the bent spring end I was supposed to put the one gear's pin. I looked at the wear marks on the orange pads and it suggested I should locate the pin to the LH side of the spring endpiece (red line in pic), but then after assembling it, I thought that maybe what seemed to be play was due to the fact that the pin should have ben installed to the RH side of the spring endpiece (green line in pic). Can someone confirm this? David, Wynn? I'll wait until I get confirmation b4 refilling with fluid.
 

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92strokedbird said:
Since i cannot see how you installed the spring,there is a method to check.Hold the rotor pack blades by the exit port of the blower.Then with your other hand turn the pulley clockwise,you should feel the resistance of the spring.It should turn about an inch or so then engage solidly against the rotors,but you must feel the spring tension.Like it would turn back itself.Check it out.;)


I get what you describe when I turn the pulley counterclockwise. Looking at what the rotors do when I turn the pulley in this direction suggests to me that the assembly turns counterclockwise as the rotors will be pushing air up and out. So, I feel tension and a springback action when I turn counterclockwise. When I turn it clockwise I just get a thud as it solidly hits the orange buffer-like piece, or at least this is what I imagine is occurring.
 
It goes on the side with the green line. Stand the case up and put the coupler on the side with the rotor pack spring down, this way you can lower the snout and align it with the three holes and not worry about the spring falling out.
 
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David Neibert said:
I can never tell which way those spring loaded couplers are supposed to go back together either, so I always replace them with a solid coupler like this one I got from Magnum Powers.

http://www.sccoa.com/forums/attachment.php?attachmentid=14983&d=1125253716

David


I think I'm gonna get one like that, either from MP or Wynn. No spring at all with that type of set up, right? Question, how does the OEM coupler come off? Just pull on it? I didn't investigate this when I had the snout off, as I never planned on replacing it. On a side note, I think it is time to do away with the spring assembly anyway b/c I noticed wear grooves in the shaft from the spring.
 
super red91 said:
It goes on the side with the green line. Stand the case up and put the coupler on the side with the rotor pack spring down, this way you can lower the snout and align it with the three holes and not worry about the spring falling out.

Thanks for your help.
 
I've never heard of anyone having problems. The coupler just pulls off, you may need to put a screwdriver behind it and pry it a bit but it should just come right off.
 
How are you overdriveing your blower? with the GTP rotor swap I had to stick to the %3 underdrive cause of bad belt slip (new belts).
 
Tickler said:
How are you overdriveing your blower? with the GTP rotor swap I had to stick to the %3 underdrive cause of bad belt slip (new belts).


10% JS OD and 5% SC pulley OD.
 
pablon2 said:
Do people increase the likelihood of breaking the gear pins (not teeth) when they switch to solid couplers (no give)? I'm referring to an MPII with 15-20% OD.
No, i've never heard of it.
 
Project Closure

Here's a little closure to this thread for those that come across this thread when searching for info on rotor pack swapping. I finally finished the swap. I say finally, b/c when I got into my SC I realized that I should replace the coupler. I was moved to do this b/c the gearshaft had wear grooves in it from the spring in the OEM coupler. After some research, I opted to install the moly-filled coupler from 'Texasthunderbirds.com' (thanks again Wynn!). Attached are a few pics. The red sealant on the flange is anerobic gasket maker Permatex item #51813 (replaces Loctite 518). Flange bolts torqued to 25 ft/lbs. Thanks to all who helped make this project a success. Rotor pack looks and feels (no play) great. :)
 

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sizemoremk said:
Its cool to use anti sieze on those right?

I imagine you could, but I was able to screw the bolts in by hand each time and noticed no material in the threads from galling, so I didn't use any.
 
Well the one I took apart was a real witch!

I'm pretty sure I broke a cheapie 1/4" socket wrench, if I'm thinking back correctly...

For that matter, I broke a cheapie autozone puller trying to get the pulley off the SC...
 
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