How to Rebuild an Eaton M90 Supercharger
The Eaton M90 supercharger is a positive displacement supercharger that is used as an OEM component as well as an aftermarket modification on many cars. This is a very reliable supercharger that regularly sees over 150,000 miles of maintenance-free performance. Like any components, though, the M90 will eventually fail. The below information will cover the snout rebuild, which is the most common area needing attention. If necessary, the main unit should be rebuilt by a professional shop.
Other People Are Reading
Things You'll Need
- Three-jaw, 5-inch gear/pulley
- Complete socket set
- Ratchet
- Extension
- Small hammer
- Set of wrenches
- Flathead screwdriver
- Phillips head screwdrive
- Snout seal
- Snout bearings
- Coupler
Instructions
-
-
1
Remove the belt from the supercharger snout.
-
2
Remove the pulley with the special pulley removal tool.
-
-
3
Unbolt the snout from the supercharger with a socket. There are probably 10 bolts.
-
4
Remove the bearing and seal from the snout by tapping a larger socket on the inner bearing to remove it.
-
5
Remove the bearing from the coupler end of the shaft with a puller to remove it from the splines. Check to see that the shaft is not scored. Clean the surfaces with Scotchbrite.
-
6
Reassemble shaft and install the new bearings. Tap the shaft back into the housing, ensuring that the bearing is seated.
-
7
Remove the retaining clip from the supercharger snout seal and set it aside.
-
8
Puncture the bearing seal with a nail on both sides. Screw two self-tapping screws into the snout seal.
-
9
Place a small wood pad between the two screws on the end of the snout and pry out the screws and seal with a screwdriver or prying tool.
-
10
Thoroughly clean the housing where the seal was with brake cleaner. Dry thoroughly.
-
11
Soak the new seal in the a bag filled with WD40 in the freezer for an hour or so.
-
12
Insert the seal as far in as it will go, which should be just past the retaining clip ring groove.
-
13
Install the retaining clip into the clip groove.
-
14
Remove the old coupler, which is often what causes a supercharger to rattle. The coupler transmits the shaft's action to the actual supercharger.
-
15
Lube the new coupler and slide it onto the snout pegs for the coupler.
-
16
Reinstall snout with the main supercharger by lining up the dowels that position it in place.
-
17
Refasten all of the bolts to 15 foot-pounds with a torque wrench.
-
1
