I was replacing the disintegrating and ineffective cork gaskets with new OEM MB gaskets + copper sealant today and got everything all ready to go and started tightening the intake manifolds. Finger tight, then 5 ft/lbs, then 10 ft/lbs. Everything looked good, then my first bolt to 15 ft/lbs... SNAP.

Sigh.

So my first question is... 15 ft/lbs is the correct specification for tightening the intake manifold bolts w/ a stock metal gasket, correct? I saw a few spots on the forum that said 10 ft/lbs but I believe those are for the cork gaskets. The SRT6 (which is what I have) service manual says 15 ft/lbs. And if it is 15 ft/lbs, why the heck did it snap on me? I had the correct setting on my torque wrench.

Second question, does anyone have a part number for a new set of bolts? I would prefer not to spend 50 bux on a new set of bolts, so if someone has a spare that I could buy off of them that would help me tremendously.

It's this one:

o

o o

o x

o

(Left manifold, center bolt closest to front of car, shown as x in my crude diagram)

Luckily it didnt snap flush to the block, there's about an inch poking out from the bottom. I'm assuming pliers and a strong grip will do it?

Thanks!

 

l run in a tap to each hole before replacing a bolt to be sure the threads are clear, using my fingers without the handle. Then using the handle, I run it in and out as the aluminum is not forgiving. 15 ft pounds should be ok but is your torque wrench able to be set there??? ie is it the same one that you use on head bolts?? I got an inch pound wrench as a smaller tool is needed here. Enjoy WDY

 

I still have stock intake manifold bolts. Take a quick measurement of which one you need and I can send it out to you. If you want a few extra or all of them, let me know.

 

Sent you a PM!

 

...Replied!

 

Yeah, I have a smaller inch/lb torque wrench, set it to 180 inch/lbs = 15 ft/lbs. Did a test with the bolt itself, only seems to take about 10 ft/lbs until it starts twisting and ready to snap.

These are stock bolts, but don't seem to take 15 ft/lbs. ???? Im confused.

EDIT: Is it possible I'm looking at the wrong specs? I'm trying to tighten the 6 bolts for the bolt holes you see in this picture:



I am using stock mercedes gaskets that go in between these and the block.

 

The bolts are tightened to 7 ft.lbs, not 15 ft.lbs
The operative word is PLENUM.

 

Well, crap. I was looking at "Intake Manifold Bolts - 15 ft/lbs". So you're saying the bolts I am tightening now are "Cylinder Head Cover Bolts - 7 ft/lbs"?



If so, why does Rob list the specs at 10 ft/lbs on the cork gasket page? Difference in material?

NeedsWings Performance Products. NeedsWings Intake Manifold Gaskets

So 15 ft/lbs is wrong, what exactly are these specs for? I see this number all over the forum, what bolts are we talking about for this spec?

 

That part is the PLENUM.
What finish do you have on yours? Teflon?

 

srt6 gasket and bolt torque specs 9-853 in the service manual


the picture in post 8 is cut off just shy of showing the next line which reads
Intake plenum to supercharger bolts at 7 ft/lbs, 10nm or 88 in/lbs


the "Intake manifold" line showing 15 ft/lbs I assume is referring to a NA intake manifold being bolted to the heads. this should be the same holes as the "supercharger to cylinder head bolts" that shows 17ft/lbs


Mercedes does not make service manuals, we lucked out when Chrysler realized that Americans would demand a service manual so we kind of got to take what Chrysler made us and overlook a few mistakes in there. the slk and c-class owners lucked out with the crossfire manual as well, or at least those that have realized it.

 

Well Dave beat me too it. I do 8 on mine, but 15 is too much....

 

Thanks to everyone for correcting my mistake. For all you future DIY'ers, if you're reading this...

7 ft/lbs

Is the number you're shooting for. These bolts won't take much over 10 ft/lbs before they'll twist and snap.

Much appreciated guys!