Dust seal 300TDi timing cover

[Finnius]

Hey folks,
I am replacing the dust seal in a 97 300TDi front timing cover. It is the latter style dust seal with a couple of metal rings the crank pulley sits in.

One side has a big rubber ring and other is just plain metal.

I am hoping someone can tell me which way to install it? Rubber side in or out? Flush with front or back of cover?

I checked 2 workshop manuals and they both neglected the details i need.
https://www.aulro.com/afvb/images/imported/2017/11/187.jpg

https://www.aulro.com/afvb/images/imported/2017/11/188.jpg

[Roverlord off road spares]

Hi Ben, googling shows these images of a new timing case with the metal cased seal fitted

132066
132067
Also looking at schematic in diagrams, it shows the timing cover then behind it the dust seal, so I would assume the seal is fitted from the behind face of the timing cover using the metal face to push it in so that the rubber face is on the front face of the cover. Having said that though I have never fitted one myself
Cheers, Mario

[Finnius]

Hi Mario,

Good idea looking up images of the later style timing cover!
I can see that the rubber ring sticks out the front of the case - presumably to press against the crank shaft pulley. I will install it flush with the back of the cover.

Thanks!

[AK83]

Hopefully this vid helps a little too:

Changing the cambelt on a Land Rover Discovery 300 TDI (HD) - YouTube (https://www.youtube.com/watch?v=_26y5pDpHzY&t=303s)

at about 7:40 they do the timing cover dust seal(if it doesn't link to that point)

Did you do the cam belt change?
Or are you replacing seal due to a leak or something?

[Finnius]

Hey,

Yep i am doing the timing belt and whilst i have the cover off I am doing the font main oil seal, fan bearing, A/C idler pulley and front dust seal for good measure.

I just hope i can get the front main oil seal out now and reinstall it - without taking out the rear timing cover...?

[justinc]

I wpuld ise the err4576 rubber dust seal personally. I have several times come across the new thicker 1 piece crank pulley rubbing on the steel dust seal. You can fit the early err4576 seal in its place to clear the pulley. The front crank seal err4575 can be hooked out but do not damage the seal bore. To refit the seal ise the old crank pulley reversed, and tap it over the crank as a guide to insert the seal dead square.

Jc

[Finnius]

Do you mean the timing belt crank pulley rubbing on the back of the metal dust seal?
If i make sure it is flush with the back of the cover (perhaps a fraction of a mm recessed) surely it wont rub?
In any event the metal seal and the crank pulley should both be turning in unison - not one rubbing on the other - as the inner metal dust jacket spins with the crank...
Thanks

[justinc]

The timing belt pulley was scuffing against the steel shell of the seal. I just removed the cover and fitted an earlier rubber seal.
Like i said only happened a few times out of all the literally hundreds i have done over the years.

[Finnius]

Could a kind soul confirm where the O-ring goes that lives behind the timing belt crank pulley...

Does it just sit on the crank and the crank pulley presses up against it? Does that mean that when i put the front harmonic balancer on that it presses up against the timing pulley which in turn presses against the o-ring?

I have found a parts diagram of the o-ring in another thread but it just shows the o-ring hovering in mid air behind the timing belt crank pulley...

[AK83]

I only did mine a few months back .. but really can't remember, other than I followed the instructions and took note of stuff during disassembly.
But having just read the instructions in RAVE, I do remember the O-ring a little.

From RAVE:


14. Lubricate a new crankshaft oil seal with clean
engine oil.
15. With lip side leading, drive-in seal squarely using
special tool LRT-12-079.
16. Lubricate new ’O’ ring seal with petroleum jelly
and slide onto shaft, taking care not to damage
seal on the woodruff keys.
17. Fit crankshaft gear, tap fully home ensuring ’O’
ring seal is properly seated.

so the O ring goes between (inner)main seal and timing belt crank gear.

[workingonit]

The o-ring stops oil from moving to the timing case shell, via the inside of the pulley.

In theory, with lube and under pressure, the o-ring should self seat inside the recess at the rear of the pulley. You should end up with metal to metal contact between the crank and the pulley, with the seal sitting snug in the recess where it does its sealing job. It should not be sandwiched/pinched/mashed between the crank and the rear face of the pulley.

In practice I find the o-ring generally will not will not self seat, even under pressure of doing up the nose bolt. Undoing it all finds the seal distorted, flattened and on the way to being sheared. I've tried other approaches like using the harmonic balance as a simple slide hammer against the pulley, but no success. Maybe the pulley recess could use a bigger chamfer to guide the o-ring to self seat?

I now resort to installing the o-ring inside the pulley recess before putting the pulley onto the crank. The bane of this order of process is working the o-ring over the last key (the first is left off for the exercise). A small portion of the o-ring is worked out of the recess to give the slack necessary to get over the key, then in the tight space left forcing the slack back into the recess - job done.