I'm only guessing here but if there are no factory specs for re-torqueing then, I suspect you will need to take the bolts out change them out with new ones and torque to factory spec's. Perhaps you can measure the bolt lengths and decide if they need changing.

I did my cylinder head because it needed new valve guides. It is a lot of work to take the head out so I do not blame you for trying a short cut. I wonder if there is a danger of causing other issues (compression leak/oil-water mixing, etc)

Assuming M102 and M103 designs are similar, I do not see oil leaking anywhere but in the right (passenger) side. All the oil channels are on that side.

 

I tried a little to figure out what engine # is, but don't know. Look here:

https://www.startekinfo.com/StarTek/outside/11832/?requestedDocId=11832

There should be a sequence to follow. Hope you have a torque wrench. If not, can get ones at Harbor Freight...

 

I think I can find sequence easily enough but can’t find torque ft lbs

 

I have that in my manual(s) at home. Will send it out if I do not get beat to it.

But the torque is a progressive thing with fresh bolts and head gasket. And it goes "like" this:

First crank to a low spec (I think 54 ft-lbs, I will send that out) using the proper bolt pattern sequence
Then crank half turn using the proper bolt pattern sequence
Then crank another half turn using the proper bolt pattern sequence

There must be a preferred method to re-torgue the bolts though without a new gasket.

If you are just torquing without removing the bolts you should be just counting 1/4 or 1/2 turns not ft-lbs (or newton-meters) as you will not find a spec for the final torgue.

If you are starting with freshly removed bolts then you would just follow the procedure I outlined above.

I will get you the exact requirements assuming no one replies before then.

 

I have that in my manual(s) at home. Will send it out if I do not get beat to it.

But the torque is a progressive thing with fresh bolts and head gasket. And it goes "like" this:

First crank to a low spec (I think 54 ft-lbs, I will send that out) using the proper bolt pattern sequence
Then crank half turn using the proper bolt pattern sequence
Then crank another half turn using the proper bolt pattern sequence

There must be a preferred method to re-torgue the bolts though without a new gasket.

If you are just torquing without removing the bolts you should be just counting 1/4 or 1/2 turns not ft-lbs (or newton-meters) as you will not find a spec for the final torgue.

If you are starting with freshly removed bolts then you would just follow the procedure I outlined above.

I will get you the exact requirements assuming no one replies before then.

Not to disagree with you dolucasi, but when I replaced my head gasket in 2007, I torqued the head bolts to 40.6 ft. lbs., then turned each bolt 90 degrees, then another 90 degrees per instructions and in the sequence recommended.

To the OP, the only oil leak problem I had was when I didn't use a MB brand valve cover gasket and I thought I had a head gasket oil leak. I ordered a MB brand valve cover gasket and problem solved.

 

If retorquing, a friend told me to back the bolt out a little and start from scratch. Would this make sense here, ie. these are not one time use, need locktite, or something?

If it's not easy for you to find, I'm guessing it will be hard for me, but I do have the original CD-ROM I bought direct from Mercedes, although the original sleeve may have been thrown by my wife accidentally.

Which engine number??? Then I can try looking when I get the chance.

 

You are not disagreeing with me SLK. If you read my email more carefully I said it goes "like" this:

Whatever I said after that was a guess before I checked my manual tonight. So you have it there. 40.6 ft-lbs followed by 2 90 degree turns.

My whole point to the OP was that one does not torgue to a spec, the final torque is by turns.

There are two paths here "after" the OP makes sure it is the headgasket that is leaking (I doubt that too for these engines)

(1) Drain the coolant below the head level and remove and replace the head bolts as specified
(2) Do not remove the bolts and just do a quarter turn (or 1/8th) on all with the sequence

I do not own a 4 cylinder but I personally would never attempt to re-torque the head gasket. If that was a tried and proven method everyone would use it. I do not believe it is a well traveled path by others.

The reason why I would not is that an oil leak is rather benign and one can not get serious oil leaks from the gasket and not have oil/water mixing or have a blown gasket. I believe an oil leak is the last thing that happens in these head gaskets. Generally it is the valve cover or timing cover or something else.

Mine is a '89 2.6 and at 190K miles and 29 years never had a drop of oil leak from the head gasket before I replaced it. Was leaking plenty from the upper timing cover.

Now 2.3's may be entirely different, and the OP needs members like you to chime in with input as mine is tangential.

- Cheers!

 

The leak isn’t coming from the valve cover nor the timing cover as that leak would originate from the front of the engine. I’ll try to find the link to the thread on here where the fella retorqued the head with positive results. The thread stated to remove 1 bolt at a time,clean, measure and retorque before moving to next bolt. He stated the bolts seated an extra half turn from original and leak stopped. I believe this was an M103 engine? I’m not sure my engine model but its a 2.3L 8V.
Here’s the link http://www.peachparts.com/shopforum/tech-help/389836-m103-head-gasket-re-torque-i-tried.html

 

Sounds like you have a plan. Not sure if you replaced your head gasket yet, but just for reference here's a picture of my old head gasket next to the new one I installed.

Good luck.:thumbsup:

 

Yep, that is an interesting method. Hopefully it works. Let us know how it turned out!

 

I haven’t replaced the head gasket however when looking at photo of your old one perhaps I should just such a big job. Am hoping for a quick fix but aren’t we all. Anyway if someone has accurate torque spec I could use them regardless

 

BTW, do not use the torque numbers he came up with in that thread. I'm pretty sure he had an incorrect start. He had a m103 engine that had different starting torque spec then he should have. He started with 41 lb-ft the M103 takes 52 lb-ft unlike your M102.

So he ended up with bolts slightly looser, and it still worked. His collected numbers are going to be similar to yours though because he torqued his head as if it was a 4 cyclinder.

- Cheers!

 

You have the correct torque specs and sequence, now it's just a matter of doing it. Are you going to check the length of the head bolts to make sure they are all the correct?
Be sure to have the 12mm Serrated Wrench fully seated into the head bolt. Also, be sure to replace the valve cover gasket with a MB brand. A few of us have had oil leaks due to the aftermarket gaskets not being quite as thick as the MB brand.

Good luck, hope all goes well.:thumbsup:

 

Are you going to check the length of the head bolts to make sure they are all the correct?

I’m pretty sure that this is a must, unless you want to have to do it again, or are very lucky!

 

So the correct specs for my engine are 41ft lbs?

 

Yes, follow SLK's numbers he already posted. You guys share the same engine (M102).
The thread you sent had some mix-up, though he gave some expected torques for his job with 41 ft-lb + quarter turn each time.
You can see if yours is simillar to his numbers but remember there is a reason why one does not torque to a final ft-lb spec.

It must be because the important issue here is "travel/compression", not torque.

So one first gets all the bolts to a moderate position at 41 ft-lbs, then one 'compresses" the head gasket equivalent to a quarter turn each time (which translates to a certain amount of compression of the gasket.

Problem is a used gasket does not compress like a new gasket does. Which is probably why what you are attempting is not an exact science.

 

Gotcha. Thanks

 

Just for reference, here's a picture of the top of block without the head and the head after having it at the machine shop.

 

That’s beautiful work! Can you trust any machine shop for that?

 

BTW, the four circular holes (in a row) on top of the cylinder head photo from SLK are the oil ports. Those are the ones you are trying to stop a leak in.

 

Nice job on your head and block!

Are these the oil ports you described?

 

Mercedes, she’s definitely high maintenance, that gal.

(I thought I was rough with her racing around when I was younger, or that and possibly using Dexcool I guess! Had head gasket done back in 2009 at a dealer)...

 

Yes, those are the oil ports. All the rest are either for the bolts or coolant passages.