I'm looking to replace the rear crankshaft seal on a 5 bearing engine.

I've just ordered a decent seal from Turner engineering.

Is it best to remove the back plate (flywheel housing) and fit the seal whilst it's on the bench, or to do it in situ?

I did this about 10 years ago to a 200tdi, I think I removed the back plate. I know I had to do it twice, the first time was with a "oem" seal (yeah, right!), the second with a genuine part.

My thinking is that, even with the plastic insert in place, it might be too easy to not have the back plate fitting squarely and distort the seal when fitting the back plate.

But if I do it the other way with the back plate fitted what's the teqhnique to getting the seal in squarely? I don't have a drift or socket anything like that size. Is it simply a matter of gently tapping around the edge until the plastic insert pops out?

And is it best to oil the crank and seal or do it dry?

Thanks in advance

First thing, very important if using genuine seal you do it dry, seal and crank journal. I do this job with the housing off on the bench. I do not have the special tool for this so tap it in with care flat on the bench. The last one I did just would not go in so put the seal in the freezer for half an hour and it then fitted with ease.
It is important not to distort the seal outer when fitting.
You should fit a new housing to block gasket, they come with a bead of sealer pre applied. It is straight forward with refit housing with the seal in place an guide on the crank. A little wiggling and pressure each side of the housing will get it there.
I do not think it is possible to do the job the "other way" as you suggest, at least not with out a special tool of some sort.but I bet someone will be long who did it that way. Cheers.

Brilliant, reply, thanks.

I can't find a gasket for a 10J engine, only the 200tdi. I'm not sure if that would fit, it looks to have extra bolt holes along the bottom.

There wasn't one on there when I removed the housing, but I guess it could've been removed and not replaced. I was going to put some silicone on there!

Bern said:

Brilliant, reply, thanks.

I can't find a gasket for a 10J engine, only the 200tdi. I'm not sure if that would fit, it looks to have extra bolt holes along the bottom.

There wasn't one on there when I removed the housing, but I guess it could've been removed and not replaced. I was going to put some silicone on there!

Click to expand...

there isnt a gasket but best practice is to use a 200di gasket and cut the the bottom of leaving a little to overlap sump edge

Great, thanks, I've just ordered one.

HI
Hopefully you ordered the Dowty seal from turners, mines been on 10 years 84 5mb Diesel and not a drip since come out of wading plug hole.
I fitted mine in situ with engine in place, plenty of room and go carefully , the sleeve helps avoid damage.
instructions on pics, don't forget the O ring

Perfect!

Yes, I've ordered the Dowty seal from Turners.

The O-ring I assume goes between the housing and the block in the indentation?

Yes correct.