Je Suis Moi

Does anyone know the torque spec and order for the M119's cylinder head bolts? I would like to retorque mine this weekend.

Thanks.

rojacobs1

I have All Data for my '96 and it gave me this-

Seems like it's way more complicated than just re-torquing to a set value.
Not sure why you would need to do it anyway, you may just be asking for trouble.



Cylinder Head Torque & Sequence

Tightening Torques And Tightening Angle Table





Cylinder head bolts, engine cold*
1st stage: 55 Nm
2nd stage: 90°tightening angle
3rd stage: 90°tightening angle
Bolts of camshaft bearing caps M7: 15 Nm
Bolts of cylinder head timing case cover M8: 25 Nm

* Moisten washers and thread and contact surface of bolts with oil before installing.






Cylinder Head Bolt (12-pt Socket with "Closed-Deck")
Thread Diameter "D" 12 mm
Stretch Shank Diameter "d":
When New 10.75 ±0.05 mm
Thread Length "a" 135 mm
Bolt Length "L":
When New 160 ±0.8 mm
Maximum Bolt Length 162.70 mm
Cylinder Head Bolt (12-pt Socket with "Open-Deck")
Thread Diameter "D" 12 mm
Stretch Shank Diameter "d":
When New 10.75 ±0.05 mm
Thread Length "a":
Short Bolt 135 mm
Long Bolt 190 mm
Bolt Length "L":
When New:
Short Bolt 160 ±0.8 mm
Long Bolt 218 ±0.9 mm
Maximum Bolt Length:
Short Bolt 162.70 mm
Long Bolt 221.60 mm

Bolt Diagram




"Closed-Deck" Cylinder Head Bolts Numbers 1 to 10 = M12 x 160 mm
"Open-Deck" Cylinder Head Bolts:
Numbers: 1, 3 and 5 = M12 x 218 mm
Numbers: 2, 4, 6, 7, 8, 9, 10 = M12 x 160 mm

NOTE: Cylinder head bolts : Cylinder head bolts match with washers. "Closed-Deck" cylinder head bolts are phosphatized, washers chrome-plated. "Open-Deck" cylinder head bolts are chrome plated, washers are phosphatized.
No "HELI-COIL inserts are installed in crankcase of "open-deck version. HELI-COIL inserts may be used when performing repairs.

cliffyk

I believe attempting to "re-torque" the head bolts on an M119 would be a big mistake-BIG!

The head bolts are of a TTY (Torque-To-Yield) design, intended to be initially tightened to a specific torque, and then further tightened in two TBA (Torque-By-Angle) stages to achieve a specific load on the bolt. This is in no doubt related to the engine's having an aluminum block and aluminum heads.

To properly "re-torque" the heads would require removing all head bolts in stages and in the reverse of tightening order as shown above, then measuring each bolt to determine its fitness for service (obtaining new bolts if found unfit), and re-installing and tightening them using the initial torque and two stages of angular tightening.

And of course when the bolts are removed the head gasket will be free to move about and break whatever affiliations it may have settled in to with the block and head--to do it 100% properly the head gaskets should also be replaced...

Je Suis Moi

Thank you both for your replies.


I still have the dreaded engine ticking even after having inspected the cam oiler tubes, finding none blown, but replacing all of them anyway.


I read on another site that someone solved the same problem by re-torqueing his head bolts and I was going to try it.

cliffyk

Have you checked for exhaust leaks at the exhaust manifold/cylinder head gaskets or the manifold to head-pipe connection? The high velocity flow of exhaust gasses through "pinhole" sized leaks can very often mimic mechanical ticking...