camshaft breaking

[julianl]

I have just replace my cylinder head gasket on my H reg 200TE and had the engine running very nicely for a couple of hours when the camshaft broke just in front of the no. 1 rocker. I got a replacement and fitted it together with two new valves, put it all back together again ran the engine for another hour or so and the second camshaft has broken again in exactly the same place. Why? As far as I can see everything is back where it should be, I do not have any bits left over....

 

[Bolide]

The tensioner was set & fitted incorrectly. Do a search on this forum - there are lots of posts about this problem

Nick Froome
www.w124.co.uk

 

[jibcl500]

You refitted the chain tensioner incorrectly putting too much stress on the chain hence the camshaft snapped.

jib

 

[television]

The tensioner should have been removed and returned to its fully closed state,,what a shame

 

[julianl]

Thanks for coming back so quickly. What am I supposed to do to the chain tensioner? When I replaced it I screwed in the piston section and then pushed in the spring and did up the covering nut.... What more should I have done?

 

[television]

I can send you the correct fitting instructions,,I take it it is the 102 engine,,just pop up your email address and you can edit it out later

 

[Alex Crow]

you should have pulled the plunger right out, fitted the tensioner body to the car, then pushed the plunger back in from the other end. when you get it apart again have a look at the design, it has a ratcheting mechanism built into it.

 

[julianl]

malcolm,

Thanks, very helpful indeed. As this will now be the third time, assuming I have a couple of bent valves again, I have taken the head off I am out to beat my previous record of four hours to take off and three to put back together. The first time took nearly three days, reading the manual at the same time. Do I need to prime the tensioner with oil and if so how?

 

[julianl]

oh, and it is a 200 TE four cylinder, don't know if that is a 102, I think it is a w124

 

[television]

It is a 102,,I have sent a pile of papers just ask if unsure

 

[julianl]

Thanks Malcolm,

see message above, edited

 

[television]

Thanks Malcolm,

see message above, edited

Good luck this time round, there is no mention of filling though that used to be the normal practice,,just make sure that it is fully closed before inserting it,,, If you need any more info you know where we are

 

[meanie]

Hate to be a party pooper, but I would consider replacing the timing chain at the very least whilst the head is off this time. To have put enough load through it to snap a camshaft twice will have hurt it. Whilst the duplex chain on the later 102 was 100% better, it will not have taken kindly to this treatment. I'm actually a little surprised that it didn't fail before the cam. A very easy job to wind one round for 2 people with the head off.

 

[television]

Hate to be a party pooper, but I would consider replacing the timing chain at the very least whilst the head is off this time. To have put enough load through it to snap a camshaft twice will have hurt it. Whilst the duplex chain on the later 102 was 100% better, it will not have taken kindly to this treatment. I'm actually a little surprised that it didn't fail before the cam. A very easy job to wind one round for 2 people with the head off.

I sent the details of this with all the things I sent,,good point

 

[Alex Crow]

shame a haynes manual wasn't looked at, would have saved a couple of camshafts and possibly a few valves.

 

[kth286]

shame a haynes manual wasn't looked at, would have saved a couple of camshafts and possibly a few valves.

I also am always surprised that people will do these kind of jobs without looking up proper instructions first - every car design has it's own individual quirks.

 

[julianl]

I quite agree, I should have looked at this section in more detail. The benefit of hinsight!!