Eaton M90 Supercharger Rebuild Kits

The Eaton M90 supercharger is a well-proven unit which is found in the Jaguar XJR X300 (XJ6-R), Aston Martin DB7 and Aston Martin Vantage 600, as well as a variety of cars in the US market.

Good though they are, these superchargers can be subject to premature seal or bearing wear, or failure of the drive coupler. Rattling at idle is the first indication that something is going wrong, usually that a bearing is starting to wear, or that a drive coupler is fractured and failing. The important thing is to have them repaired when you hear early signs of something being wrong – if they are left rattling too long and the damage will spread from bearing wear, which is curable, to wear of the rotors and/or main casing, which can become bad enough to scrap the supercharger.

Replacing the Bearings & Oil Seals

Replacing the bearings and oil seals in your supercharger will give it a new lease of life, and your own peace of mind. As long as issues are identified and repaired early, our Eaton M90 supercharger rebuild kits, which are £95, should fix the problem. You will need access to a workshop press but other than that the job is not beyond the ability of a competent mechanic.

The kits include front and rear snout bearings, snout oil seal, rear needle roller bearings and the required oil to fill the supercharger after reassembly.

M90 Snout Rebuild Kit

If your problem is just a leaky snout oil seal, or you’ve stethoscope and confirmed that just a snout bearing needs to be replaced, then our Eaton M90 snout rebuild kit at £46 may be the most cost-effective way to have your car back to good health. The snout rebuild kit includes front and rear snout bearings, snout oil seal and the required oil to fill the supercharger after reassembly. BUT – if there’s any doubt over the condition of the rear bearings, it would be advisable to change them as well. The rear bearings are prone to failure, and you may wish to avoid a future repeat of the process to remove and refit the supercharger for the sake of two more bearings first time around by buying the full rebuild kit!

Rotor Pack Bearings & Seals

Our M90 supercharger rebuild kits do not include the pair of bearings and seals which live between the rotors and timing gears in the middle of the rotor pack. This is because at manufacture Eaton rolls the casting onto the bearing outer race, permanently sealing them in and meaning the casing has to be fractured to remove those bearings. That said, these are in an oil bath and rarely fail – when we are rebuilding superchargers we do not change the rotor pack bearings. If they do fail, some service providers in the US do offer rebuild of the rotor pack, but the Eaton Corporation themselves consider this to be an unreliable and often unsuccessful route to repair – when the rotor pack is worn out or damaged the only dependable solution is a new rotor pack.

If you want to attempt to rebuild your Eaton M90 rotor pack we can supply you the parts, but caution that it is not a straightforward task.

Preventative oil changes are very important on Eaton superchargers, as the ‘sealed for life’ claim is at best an aspiration, and repairs can be expensive. Although Eaton uses a high quality synthetic aviation turbine oil in its supercharger range, the oil is not indestructible and does oxidize gradually over years of exposure to high working temperatures – it just lasts longer than a plain mineral oil would.

After only 50,000 miles, the original oil can have degraded from the nice clear sample on the left to burnt-smelling brown soup like the right hand sample – not good for protecting the bearings and seals in your Eaton M90 supercharger!

We have a range of oil refill kits which include the required quantity of oil for your Eaton supercharger, with a syringe and tube to aid removing the old oil and filling with the new.