Clutch or flywheel removal and rear main oil seal replacement

Clutch or flywheel removal and rear main oil seal replacement, for Jetta Passat TDI
difficulty: 3/5
back to 1000q: mk3 FAQ and "how to" index"

Introduction

This article gives tips on removing the clutch/flywheel and replacing the rear main oil seal. If you remove the flywheel and your car has higher miles on it, it's a very good idea to replace the rear main oil seal. This project is rated 3/5 difficulty only because it requires transmission removal, once the transmission is out it is an easy job.

There are two types of rear main oil seals (RMS) on the TDI, rubber lipped type with spring or the flat paper-like teflon/PTFE seal. The rubber RMS has two lips and has a metal spring on the inside edge. The advantage is that this is the more conventional type of seal and can be easier to install. The disadvantage is that if there's already a groove worn into the crankshaft from the old seal, this seal may not seal it completely unless it wears into the same groove. The teflon type (pictured below) is a papery-plastic like seal with no metal spring and should be applied dry. The advantage is that it has a wider lip that sweeps across the running surface of the crankshaft and leaves no groove. If there is a groove, the seal can "bridge over" a small groove and can seal better than a rubber type. Teflon seals are also more durable and slippery. Although a seal can be difficult to install, your RMS should come with a plastic guide sleeve installation tool. It only fits one way and guides the RMS onto the crankshaft by stretching the seal a little bit for installation. I am told that if you use a teflon seal you should also stay with that type of seal to prevent leaks although since it shouldn't wear a groove into the surface I am not sure on that.

Parts

12 point sockets
10mm sockets
torque wrench
flywheel holder (or make your own)

6x 12 point bolts (one use only) VW# n 902 061 03
6x flywheel bolts (one use only) VW # n 101 010 01

For rear main seal replacement
T-40 torx
rear main seal VW # 028103171B available at tdiparts and worldimpex, worldimpex generic seal
OR rear main seal VW # 068-103-171-F
oil pan gasket VW# 044-103-609-D or generic worldimpex

misc notes and optional part list

The stock clutch was a 228mm sachs clutch with a solid flywheel. The clutch and pressure plate (and part number) is specific to the TDI.
stock pressure plate VW# 044 141 025 x or #074 141 025 b
stock clutch VW# 028 141 035c or 028 141 035bx
stock flywheel VW# 028 105 269 b (rebuilt so it has an "x" suffix)
clutch pivot ball pin VW # 02a 141 777b
clutch fork VW# 02j 141 719 c
clutch fork spring VW# 012 131 741
release bearing is VW# 02a 141 165 g , from worldimpex, sfk bearing

Procedure

Clutch/flywheel removal

Remove the transmission. See 1000q: transmission removal for mk3 for more details. I don't suggest using air tools inside the bellhousing since it blows clutch dust all over where it can be inhaled. Use a wet rag to wipe off the dust.

To remove the pressure plate, use a 12 point socket to remove the 6 bolts. Below is a picture during installation, the bolts were removed. I put a socket in the middle of the clutch to align it.

To remove the flywheel, counterhold the flywheel and remove the 6 bolts holding the flywheel. Do not counterhold it by the 19mm bolt at the harmonic balancer/serpentine crankshaft bolt at the other (front) end of the crankshaft. It's ok to use that bolt to gently turn over the engine but you should not apply any significant force to it since it is a 1 use only stretch bolt. You can thread some of the transmission bolts back into place or use a VW tool or a generic flywheel holder (pictured below at picture bottom) to hold the flywheel. Note that it should only go on 1 way due to the bolt hole alignment. This puts the TDC mark at the correct spot.

As mentioned in 1000q: clutch FAQ , the TDI clutch is pretty robust and the flywheel on my car (street use only) did not show much wear when I removed it. I see no reason why you would want to put a dual mass flywheel (DMF) to replace your single mass flywheel. I reused the single mass flywheel by scrubbing it with scotch-brite pads and then thoroughly cleaning it with brake cleaner. Disclaimer - this was what I chose to do on my car only, have your flywheel inspected by a professional for cracking, warping, hot spots. You may need to have it resurfaced before attempting to reuse it Before putting it back on, I marked the TDC notch with paint for easy identification.

For installation, use all new flywheel and pressure plate bolts.

You can put a very thin smear of high temp grease on the splines. If in doubt, less is better since you don't want grease on the clutch. Wipe down the flywheel and pressure plate surfaces with brake cleaner before installation to remove machining oil. Note that the flywheel bolt holes will only align in one direction so that the TDC mark is in the correct position. The VW flywheel bolts come with threadlocker, I would also suggest light strength threadlocker on the pressure plate bolts since you don't plan on removing it soon.

flywheel bolt torque: stage 1: 22 ft-lbs. stage 2: 44 ft-lbs. final stage: additional 1/4 turn (90^o turn)
pressure plate bolt torque: hand tight, then tighten diagonally or in a pattern, in stages, to a final torque of 15 ft-lbs. Tightening in stages like 2 turns each, diagonally across the pressure plate in a star pattern keeps it flat while tightening.

Rear main seal removal

Remove the shield (3x 10mm bolts) circled in yellow below.

Remove the RMS flange. Note that it uses (2x T40) torx bolts on the oil pan. Do not pry close to the flange surface! The area outlined in red is a safe place to pry it out.

Below is the end of the crankshaft exposed. Note - I didn't cover the CV joint with plastic wrap because I was going to replace it anyways. Scrub away any corrosion on the block and wipe clean. The correct method to replace the RMS flange is to remove the oil pan, install the rear main seal, and then install the oil pan with a new oil pan gasket. This ensures that the flange is sealed correctly at the corner. I put some gasket maker on the corners before putting the new flange in and there are no leaks.

Scrub the rust off with scotch brite and wipe clean.

There was a paper gasket in the ETKA that goes under the flange but mine had none and the flange also had a rubber seal against the engine block. If your engine is like this, I would not use the paper gasket.

If you are using a teflon type seal, install it dry (no oil or grease) and always use the install guide sleeve to prevent damage to the seal. From what I've heard, teflon works better on diesels so don't worry if you had a rubber-spring type seal.

Torque for the rear main seal flange is 7 ft-lbs. There is no torque listed in the bentley manual for the oil pan-rear flange torx bolts so use an educated guess.

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