Jvenne86

well i will be installing injectors here soon and i am wanting to retorque the head bolts. now i know i have to do them one at a time but do i do each one to the full spec and degree or break one loose and torque to the first step and then go to the next one and so on. then come back and do the second.

Paul Winey

Unless you've had the head off I would leave them alone. If there is a leak then you would be better off with a new gasket.

If I can ask, why do you think you need to retorque the head bolts. I know on a 12 valve that they are made to stretch just a bit at proper torque to clamp them down. Not sure about the 24 valves, but just never heard of anyone retorquing them just for fun.

Jvenne86

i am wanting to try and retorque it because it leaks a very small amount of water at the very front of the passenger side. i have to ad maybe a half gallon every to weeks. i am wanting to get by until this fall. i plan on buying a used head off of ebay when i find one and have it gone through and machined for orings.

05CTDN8

Talking to some very knowledgable folks, instead of head stud they recommend pulling one bolt at a time, run a thread die in and clean the hole out. Use moly lube on the bolt threads AND HEAD. You do not want and friction during the process. retorgue to factory specs. Heat it up...cool down retorque in small steps to XXX ft/lbs. I need to find the value for XXX .

I am not putting out enough to really NEED head studs. And I could use the money else where.

dieselfan

kinda old thread..

heres how i did my retorque, broke em loose one at a time added oil to bolt, then torqued one at a time to 90, 100, 105, 110, 115, 120. they started turning more than i liked after 120 so i stopped.

this was not for fun it, is for insurance till i get studs.

Mike Holmen

You could also use an oil additive like STP on the bolt threads. I think that you're head gasket is blown if you have a coolant leak. The head comes off pretty easy. Leave the exhaust manifold bolted on, just unbolt the turbo from the manifold. Remove injector lines, push rods, injectors and rockers. I bet for a first timer, you could be fixed in 4 to 6hrs of wrenching. Head studs are abit more time consuming. Orings you have to get them done at a good shop to get them to work right. I've done three head gaskets and two cylinder head replacements this year. Its not that bad of a job. Engine hoist comes in handy for lifting the head off the engine, its one heavy mother.

samiam4

Maybe I'm just strange...

If you want to get consistent-factory tension in the head bolts. Follow the manual- no STP, no Moly. Use engine oil on clean threads. Lowering friction changes bolt tension. Best lubricant General Dynamics found in testing many was actually- LARD.
Studs with the same torque, you get higher tension force in the shank. They have higher fatigue allowables which is part of the preference. Also racers whom take motors apart a bunch find less problems as they are not messing with threads in Alumimum blocks.
Michael

CamperAndy

Just add to this.

Adding friction modifiers to the bolts will adversely affect the true torque as the turning friction is accounted for in the torque spec. Also on any blind holes you want nothing in the bottom of the hole, no oil, grease or even lard. It will cause a hydraulic lock and you will reach the final torque before the bolt is even close to tight. Engine oil is the only lube you ever need and even then just enough to wet the threads.

Try a google search for "torque specification" and you will find that 99% of the specs indicate "clean dry threads".

Mike Holmen

I was told to use STP on my studs and crank them up to 135ft-lbs. How much lube you putting on? Mine just come out thru the bolt holes. There enough junk (coolant, oil, rust, dirt) in the holes to cause issues, so use air hose and make sure they are clean. You can feel when the stud bottoms out. The stock bolts shouldn't bottom out. Which everway you go, for an engine less than 50psi of boost, you should be fine with the stock parts. If my memory is correct the book say 75 ft*lbs plus a 1/4 turn, dry, so go from there. There are many many ways to get this to work. Also use a recently calibrated torque wrench on the bolts. I found out that my old wrench was not quite calibrated the hard way. If you can get 120ft*lbs on a stock bolts, why not. On a new gasket, let the motor sit over night, retorque. Start motor up and bring the motor up to temp, no boost. Re-torque. You should be good at that point. O-rings, you just keep on re-torquing and get that o-ring compressed. Good luck and have fun