Just got a valve job on my head. Re-installing the head is challenging.

Removing the upper timing chain gear was relatively easy. The opposite is not true.

I did not have or need the special tool for removing the chain tensioner. I was able to remove the cap and spring and the chain and timing gear slipped right off the camshaft. Upon reinstalling it, I now see that the tensioner pushrod won't go all the way backwards into its recess.

Is there any tip or trick to re-seat the tensioner pushrod without removing the whole chain tensioner?? Please say yes...

If not, is there another tool that'll take out the tensioner?? That internal 12(?) point retaining ring looks like about 18mm...

I am totally stuck without help...

And one other thing: While monkeying with the whole thing, I broke the driver's side chain guide... (Plastic) How critical is this? Replacement requires pulling out everything on the front of the engine including the harmonic balancer and as I read it, the oil pan!

Many Thanks!

I'll assume that you're dealing with a 300E or something similar?
Once the tensioner is extended, it has to be removed, taken apart and reinstalled. The plunger will only go out toward the chain, not back. You take it out and pull the plunger out the end. Then slide the plunger back in from the "outside" end, slide it in and tighten the retaining ring. Wait until the chain is connected to put the spring back in it. The threaded ring should be a 17mm Allen(it's been a while, maybe a 19 mm?).
If you destroyed the chain guide, the front cover has to come off. The oil pan just needs to be loosened slightly about half way back to get the cover off. If it just got chipped don't worry about it.
Regards,
Randy D.

Yes, it's a 103 engine on a 1987 260E car. I guess I trashed the chain guide on the driver's side. It broke in half below the pin on the head.

That tensioner threaded ring isn't an allen, but a 12(?) point type. Does anyone butht e dealer have such a tool? What is the tool properly called?

Thanks for the help!

I had to remove my tensioner, so I just went out and did it. The first allen cap is a 12 mm. This allows the spring to be removed. The second, or internal is a 12 point threaded ring that can be removed with a regular hex 17mm allen key.

Disassemble by pressing the pressure pin out of the larger body. Then clean the parts. Put the outside housing back into the bore. Screw the threaded ring back into the bore.

Inserting the pressure pin into the housing is OK at this point, but do not re-insert the spring and put the cap back on without a chain installed.

__________________
Michael LaFleur

'05 E320 CDI - 86,000 miles
'86 300SDL - 360,000 miles
'85 300SD - 150,000 miles (sold)
'89 190D - 120,000 miles (sold)
'85 300SD - 317,000 miles (sold)
'98 ML320 - 270,000 miles (sold)
'75 300D - 170,000 miles (sold)
'83 Harley Davidson FLTC (Broken again) :-(
'61 Plymouth Valiant - 60k mikes
2004 Papillon (Oliver)
2005 Tzitzu (Griffon)
2009 Welsh Corgi (Buba)

<< Steve Wrote: "That tensioner threaded ring isn't an allen, but a 12(?) point type. Does anyone butht e dealer have such a tool? What is the tool properly called?"

Thanks for the help!


__________________
-Steve>>

The special tool is called a 17 MM Allen socket . There is no special 12-point tool for the job...no kidding.
Regards,
Randy D.

The threaded ring is tightened to 30 Nm and the screw plug is tightened to 50 Nm.

__________________
Michael LaFleur

'05 E320 CDI - 86,000 miles
'86 300SDL - 360,000 miles
'85 300SD - 150,000 miles (sold)
'89 190D - 120,000 miles (sold)
'85 300SD - 317,000 miles (sold)
'98 ML320 - 270,000 miles (sold)
'75 300D - 170,000 miles (sold)
'83 Harley Davidson FLTC (Broken again) :-(
'61 Plymouth Valiant - 60k mikes
2004 Papillon (Oliver)
2005 Tzitzu (Griffon)
2009 Welsh Corgi (Buba)

Well I cant give you any useful tech help like the previuos mebers did .But I do want to offer you some encouragement try to relax and enjoy what you are doing even if you have to walk away from it for afew hours and get your self together goodluck