I was in the process of re-installing the new tensioner lever into my 300SDL. The big hex bolt that connects the tensioner to the block... I have used the big 1/2 drive to tighten the big hex bolt - I wanted it snug but it felt like it gave in at little at the end... I removed it and inspected the threads... don't seen anything bad but I'm afraid to tighten it again. I HOPE and PRAY I didn't strip those threads!

Can somebody plz provide a quick spec for tightening torque for this big bolt?! Again, it's the tensioner that has the idler pulley and shock absorber installed to each end of it.

Quick help will be appreciated.

James

__________________
1987 Mercedes 300SDL; SOLD
1985 Mercedes 300D; SOLD
2006 Honda Pilot - wife's ride; 122K;
1995 Toyota Land Cruiser - 3X locked; 182K

it's a 16 or 18 mm hex from memory, spring one side and damper the other, that one?

It *is* a nasty one, everyone thinks they either cracked the block or stripped the thread, I don't know the factory settings, did both of mine by hand with a proper hex key and a ring spanner to lever until it felt right. I do know one person who broke the block.... so on that data point alone it appears that the block will fail before the threads...

My advice is watch it, open the bonnet every day or two for 3 months, if it hasn't moved by then you'll be OK.

100 nm


the "bearing pin" ?

I'm talking about this bugger in the photo below:

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__________________
1987 Mercedes 300SDL; SOLD
1985 Mercedes 300D; SOLD
2006 Honda Pilot - wife's ride; 122K;
1995 Toyota Land Cruiser - 3X locked; 182K

That's the one.

I *think* from memory it's around 55-60 ft/lb

You did remember the big flat washer that was between the tensioner and the chain cover?

__________________

Gone to the dark side

- Jeff

Yes sir, I did... I'm thinking of using thread lock on that big bolt?!

__________________
1987 Mercedes 300SDL; SOLD
1985 Mercedes 300D; SOLD
2006 Honda Pilot - wife's ride; 122K;
1995 Toyota Land Cruiser - 3X locked; 182K

1.Thread lock on the portion of the Bolt that fits into the Aluminum Timing Cover.
('Careful,don't want any of that Loctite into the Engine Oil)

[And Yeah,they're calling for "Clean thread and coat with sealant."]

2. A Timesert insert into the Timing Cover [Would be a Permanent Fix]
BUT you'd wanna R+R the Timing Cover to do that.The threaded Bolt hole
is open to the Timing chain cavity on the Inside.

[I feel for you,I was the Over Torque champion in Jr. High."What's a Torque Wrench and why would you need one?]

1 N-m = 0.737561 lb-ft
100 N-m = 73.7561 Lb-Ft

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__________________
'84 300SD sold
124.128

Thanks - what is the 'Timesert' insert?!

__________________
1987 Mercedes 300SDL; SOLD
1985 Mercedes 300D; SOLD
2006 Honda Pilot - wife's ride; 122K;
1995 Toyota Land Cruiser - 3X locked; 182K

http://www.google.com/search?q=Timesert&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-USfficial&client=firefox-a
similar to helicoil...

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

I replaced this one on mine half a year ago.
Can't remember any hazzle with it. Just unscrewed the old one and put the new one back in.

If the treads look fine, I'd just put it back in and tighten it firmly. A little locktite wont harm, but shuldn't be necessary.

__________________
-1992 300 TD Turbo
-198 2600E
-2004 E240 4matic LPG
-2000 Jeep
Editor, Norwegian Mercedes-Benz Enthusiasts Club Magazine MB Tidende www.mbentusiastklubb.com

Thanks - what would it take to remove that timing cover to do the TIME SERT repair, I wonder (worst case scenario)?! Would it require removal of the engine?

__________________
1987 Mercedes 300SDL; SOLD
1985 Mercedes 300D; SOLD
2006 Honda Pilot - wife's ride; 122K;
1995 Toyota Land Cruiser - 3X locked; 182K

To R+R the Timing Cover you're gonna remove Everything attached to it.
All the "S" Belt tensioning equipment,the Vacuum Pump,Radiator Fan + Clutch,
the H2O Pump.'Have to R+R the Harmonic Balancer system and the Crank Hub.
You would want to R+R the Oil Pan.the Valve Cover of course will come off.

It's a real Task.

The Timesert requires drilling out the existing Hole and Re-threading it to the
new larger diameter to enable the SINGLE PIECE STEEL Timesert(Which has
the same bore and thread inside as the existing "Buggered" thread.)

If you can see no CRACKS in the Timing Cover and it's threads look Good,All
you can do at this point is clean everything up real good and ReTorque the
Bolt .(With a little Loctite).

__________________
'84 300SD sold
124.128

I used lock-tight on mine also. Not much, but just a dab. I also torqued it by feel. It actually came loose once after I didn't tighten enough and caused the fan to start hitting the tensoner.

__________________
1995 E420 152k
1991 300D 2.5 348116 daily driver
1992 300E 2.6 196k-work in progress(head gasket)
2002 BMW 745Li 93k

Yep, think I'm f&&&ed... tried to re-tourque the bolt and it went slack on me... it turned all the way around on me - I must have stripped the threads for good!!!

That's how you make a 1 hr task into a 3 month project

Could I use JBWeld to weld that bolt into the block? I know JBWeld is good stuff and it can withstand temperature, but I'm not sure if there is any amount of tension on that big bolt from that spring - I know JBWeld doesn't tolerate twisting and torquing very well... dang it!

It's not a good fix - I won't be happy with it but it may be the only thing that will get me back on the road... opinions, please?!

__________________
1987 Mercedes 300SDL; SOLD
1985 Mercedes 300D; SOLD
2006 Honda Pilot - wife's ride; 122K;
1995 Toyota Land Cruiser - 3X locked; 182K