front timing cover leak

[Big Ron]

Could anyone tell me how long it takes to dismantle , reseal, and reassemble the front timing cover to repair a small leak on my 1997 320E , straight six? Also ,since I can't find a manual or even pictures to help, what has to be removed to gain access? How long will this job take, tools needed,etc. ANY HELP WILL BE GREATLY APPREIATED. BIG RON

I did this on my 1992 300e 2.6

Removed valve cover, collant pipe that runs in front of cover behind fan belt.

Removed fan shroud.

Removed distributor cap and rotor.

1/2 day job. Be sure the use proper sealant when installing seal.

Search this forum , lots of posts on the subject.
Joel

[deanyel]

i agree with the last post on the 103 motor - but think a 104 motor is a little bit tougher - never actually done one though. Someone should know about the 104.

[stevebfl]

If you are lucky you may only have to remove the timing cover and reseal it. The real problem is likely to require the head gasket replacement. Some of all that is explained here: http://www.babcox.com/editorial/ic/ic100345.htm

BTW, I might point out that three of the pictures in the article were donated by Jim Ellington. They are the two which have a blue towel in the picture and the one of the switchover valve. Thanks again Jim!

My tech went right through those areas before I could get the pictures. Its unfortunate that they reduced the frames so much to put the article online.

[Kestas]

I did the timing seal on my M104 last year. I can't say what the minimum steps are involved since I did the head gasket at the same time.

I believe the following need to be removed:
- fan shroud
- fan assembly
- valve cover
- coolant crossover tube

There is no distributor on this engine.

Take pictures or make good drawings so you can put the vacuum lines back in the proper location. I met with some confusion there during assembly.

Basides the u-shaped gasket, be prepared to replace the o-rings for the water passage in the upper cover and the o-rings for the crossover tube.

It is specified to use Loctite 5090 sealant (MB Part No. 002 989 73 20 10) for the vertical sealing surfaces of the upper timing cover and a bead at the corners of the gasket seal. Don't add it to the gasket or o-ring seal surfaces. Let those gaskets do the job on their own. I like to prep all sealing surfaces with Scotchbrite to ensure as perfect a surface as possible and coat all o-rings and gaskets with a thin coating of silicone grease - just enough to make them shine. I believe it helps during installation so they won't bind and helps them seat into a natural position. I don't like to install any gasket dry.

The dicey part of the job is when you reinstall the upper timing cover. It is tough to locate it properly onto the surfaces without snagging the u-shaped seal. Practice a bit with some dry runs before putting sealant on the surfaces. You'll understand when you get to that point. You don't want to do this job twice!

[Big Ron]

Thanks for all the help , guys! Big Ron

[brewtoo]

Originally posted by stevebfl
Some of all that is explained here: http://www.babcox.com/editorial/ic/ic100345.htm

Hey Steve, great article! Are there any other jewels hidden in that site??

[stevebfl]

I have writen seven articles for them ("Import Car"). A couple of those articles appear here on the DIY area. If you wish to see the rest of my articles go to www.import-car.com and click on the "search back issues" link on the left column. Enter my name Steve Brotherton in the search and search.

The magazine is a trade publication intended for technicians. Entering Mercedes in the search will find other articles; I know there is one on V8 timing chain issues written by Steve Louden of Louden Motorcars in Dallas

I did a lot of reading before I did my seal.

Be sure to use the correct loctite referenced in this string.

I got mine at Fastlane.

Joel