Rear main seal installation tool

NOTE: You only need this if you're working with the 8 mm thick oil seal.

Long ago, the rear main seal was 10 mm thick and was installed flush with the back of the bearing carrier, so it was pretty easy. Then, for whatever reason, the seal was replaced with one that is 8 mm thick. And this one is to be installed to a depth of 2 mm from the back of the bearing carrier.

Here's what IMZ (the Ural factory) said about it in 2018, along with their photo:

IMZ would like to inform you that since 20.07.2016, VIN X8JL40018G0226493 (truck Europe 9/2016), engine rear case has seal VITON 55x80x8 (IMZ-8.108-01081-02) with 8 mm height installed instead of 10 mm height seal VITON 55x80x10 (IMZ-8.108-01081) for the flywheel.

Seal VITON 55x80x8 (IMZ-8.108-01081-02) is pressed into the rear case with 2 mm recess to the rear case surface."

After messing one up during installation and eating the rather high cost of an OEM rear main oil seal, we decided to design a little tool to make the job easier to do accurately.

If you've got a 3D printer or a lathe, you could spin one up pretty quickly on your own.

Color may vary, and it's entirely possible you'll get one with some smears of other colors mixed in. We get these printed by our friends at Schimmel Engineering, who use whatever plastic filament they happen to have on the printer to keep the costs down, and we don't fuss about the cosmetics.

Instructions for use: Make sure the bearing carrier is clean. Do not apply sealant between the seal and the carrier. With your fingers, get the seal pushed into the hole slightly, such that it stays in place on its own. Then use the "pointy" end of this driver and a rubber or plastic hammer to drive the seal in carefully. Until the seal is at least 50% installed, stop and check your work often to make sure you're not getting it crooked. Once it's far enough in, you'll be able to whack the back of this driver as hard as you like, until it bottoms out against the bearing carrier, leaving a 2 mm gap between the outside of the seal and the bearing carrier.