G'day folks,

I've just finished changing the front crankshaft seal on my 1981 W123 300D...

I followed the instructions on the DIY links on this site and all seemed to be well - the plastic cup special tool worked a treat.

However, as the upper oil pan is not perfectly aligned with the block it was very difficult getting the seal to fit. It went in - in the end - but the outside of the seal ripped. I've finished the job and so far there is no leak but I guess it won't last for ever!

So here is the question - is it a good idea to loosen the bolts on the upper oil pan and re-align it so there is no longer a misalignment of about 0.5mm (before fitting another front crankshaft seal)?

I guess I'm most likely to replace one leak with another - but you never know perhaps someone else has had this trouble and has done a fix before?

Here are some pictures that if you look carefully show the badly aligned joint.

Thanks in advance for any advice you may give.

Attached Thumbnails

     

Perfect surface alignment does not matter if it is fully seated to the engine block.
If it does not leak = all is good...





Have a great day.

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Assuming the Upper Pan was never off it sould have been aligned from the Factory.

If you loosen the Pan there is no gasket just sealant on it so if you cannot re-seal it you could end up with a leak somewhere else.
Also, in theory ounce the Pan is loose you are supposed to align it with a Special Tool before you tighten it.

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84 300D, 82 Volvo 244Gl Diesel

What does the tool do ? I'm getting ready to pull mine.

.

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Experience : what you receive 3 seconds after you really needed it !!



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Thanks for the responses - if I find a link for that special tool for the upper oil pan I'll post it here.

Good lord. I have been looking in the Factory Service Manual CD and I do not see that tool.

So now I do not know if I just cannot find it or if I made mistake and there is no tool at all.
I am going to look in the printed book and chec.

OK I looked through the paper Engine manual and could also find no Oil Pan Centering tool.

So I am just going to beg for mercy and hope that my Apologia for being wrong is accepted.

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84 300D, 82 Volvo 244Gl Diesel

Thanks for letting us know!

I'm waiting for something about the upper oil pan to come up in this epic:-

http://www.peachparts.com/shopforum/diesel-discussion/272444-konstans-1982-300d-engine-out-thread-post2418370.html?highlight=upper+oil#post2418370

Here's another one for the upper oil pan

upper oil pan gaskets?

Truthfully. I don't think there is any type of sealant or glue from the factory. Just a highly machined fit. But IMHO once you disturb it, you'll need to seal it.



I just aligned by sight.


.

__________________
1983 123.133 California
- GreaseCar Veg System

I would put a small amount of a good quality silicone on the seal before I would move the pan around. On the seal only , not on the pan/block surface, as I would not want any squeezing into the interior of the engine and coming off to clog something.

If I were you I would be concerned about the seal ring surface...it looks grooved to me.

Nice job cleaning the block and pan.

__________________
Diesel-guy

Hi Brad,

As everything is back together I'm going to wait until it fails - so far it seems OK as nothing is leaking.

I'm glad you appreciate the clean up job I used brake cleaner and lots of rags!

That's what I'd do!

Much better than "If it doesn't leak, take it apart to find out why".

__________________
Charles
1983 300D, bought new, 215k+ miles, donated to Purple Hearts veterans charity but I have parts for sale: http://www.peachparts.com/shopforum/mercedes-benz-cars-sale/296386-fs-1-owner-83-mb-300d-turbo-rebuild-parts.html

Update:-

The front crankshaft seal lasted about 4 months - I've now removed the engine (to do some other stuff as well) to see if I can get it all nice and leak tight

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

It's always more fun to do things a couple times than to do them right once!

Although it is probably possible to get the alignment of the upper pan to the front cover without a special tool, in the interest of have more complete info on doing this task here is the alignment tool info:

617 589 00 14 00 Sleeve
Use/specification:

Engines 617.95
Sleeve for centering the front cover and oil pan to crankshaft.

http://www.startekinfo.de/etools/content/tool.jsp?toolno=617 589 00 14 00

I was not able to connect to the above link.

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Gary
OBK #37