Big Brown delivered stuff friday! First thing this morning I started pulling my intake off to replace the knock sensors and add a remote oil pressure sensor. Things were going great for doing this for the first time, had my new Service Manuals.

Had it all back together and started torquing the intake screws, 45 foot pounds per the book to start. Well #1 screw proceeded to snap off in the head? Only had about 4 threads showing.

Can these screws be purchased at Auto Parts stores or do I have to wait until Monday to order. Notice, I'm being positive about digging the broken screw out of the head,

 

Wtf keep us posted, most likely a specialty screw, but I snapped my shock screws and Ace Hardware had the exact match...

There is a "fancy" number on the screw that can be matched 100%

 

Your torque is too much, I seem to recall the intake torques are in in/lbs. Think you need to read the manual.

 

He still had 4 threads showing so was not even starting to torque down if I read that initial post correctly...

 

45 FOOT POUNDS!

Straight from the service manual:

"Tighten the intake manifold bolts. Tighten
Tighten the intake manifold bolts a first pass in sequence to 5 N·m (44 lb in).
Tighten the intake manifold bolts a final pass in sequence to 10 N·m (89 lb in). "

I strongly recommend replacing ALL of them is you really used 45 FT/LBS.

Heres the entire procedure:

Intake Manifold Replacement
Removal Procedure

Important
The intake manifold, throttle body, fuel injection rail, and injectors may be removed as an assembly. If not servicing the individual components, remove the manifold as a complete assembly.






Drain the cooling system. Refer to Draining and Filling Cooling System in Engine Cooling.
If replacing the intake manifold, perform the following:
Remove the throttle body. Refer to Throttle Body Assembly Replacement in Engine Controls - 5.7 L.
Remove the fuel injectors. Refer to Fuel Injector Replacement in Engine Controls - 5.7 L.
Remove the right fuel rail cover.



Remove the left fuel rail cover.



Remove the fuel feed hose. Refer to Fuel Hose/Pipes Replacement - Engine Compartment in Engine Controls - 5.7 L.
Disconnect the evaporative emission (EVAP) canister purge tube from the intake manifold.
Disconnect the EVAP canister purge tube from the EVAP canister purge solenoid valve.
Remove the EVAP canister purge tube.



Disconnect the EVAP canister purge tube from the EVAP canister purge solenoid valve.
Disconnect the EVAP canister purge tube from the fuel feed pipe.
Remove the EVAP canister purge tube.



Disconnect the throttle position (TP) sensor electrical connector.
Remove the coolant air bleed hose. Refer to Coolant Air Bleed Hose Replacement in Engine Cooling.



Reposition the throttle body heater outlet hose clamp at the throttle body.
Remove the throttle body heater outlet hose from the throttle body.
Remove the throttle body heater outlet hose.



Disconnect all the fuel injector electrical connectors (1).
Disconnect the EVAP canister purge solenoid valve electrical connector (2).
Disconnect the electronic throttle control (ETC) electrical connector (3).



Remove the EVAP canister purge solenoid valve from the bracket.
Disconnect the harness clips at the fuel rails.
Reposition the intake manifold branches of the wiring harness.



Disconnect the power brake booster vacuum hose at the booster.



Remove the knock sensor wire harness (1) clip from the fuel rail stop bracket (2).



Remove the TP sensor harness clip from the positive crankcase ventilation (PCV) tube.
Remove the PCV tube from the right rocker arm cover and throttle body.



If equipped with the regular production option (RPO) LS1 engine, remove the PCV valve pipe from the left rocker arm cover.



If equipped with the RPO LS1 engine, remove the PCV valve pipe strap nut.
Remove the PCV valve pipe from the right rocker arm cover and intake manifold.



If equipped with the RPO LS6 engine, remove the PCV valve hose (1) from the valley cover and intake manifold.



Remove the intake manifold bolts (1) and fuel rail stop bracket (2).
Position the intake manifold forward.



Disconnect the manifold absolute pressure (MAP) sensor vacuum hose.
Disconnect the MAP sensor (3) electrical connector.



Remove the intake manifold.



Remove the intake manifold gaskets (1). Discard the old gaskets.
Clean and inspect the intake manifold. Refer to Intake Manifold Cleaning and Inspection in Engine Mechanical - 5.7 L Unit Repair.
Installation Procedure

Important
DO NOT reuse the intake manifold gaskets. Install NEW intake manifold gaskets.






Install NEW intake manifold gaskets (1) to the manifold.



Install intake manifold.
Position the intake manifold forward.



Connect the MAP sensor vacuum hose.
Connect the MAP sensor (3) electrical connector.
Position the intake manifold into place.



Apply threadlock GM U.S. P/N 12345382, Canada P/N 10953489, or equivalent to the threads of the intake manifold bolts (1).

Caution
The fuel rail stop bracket must be installed onto the engine assembly. The stop bracket serves as a protective shield for the fuel rail in the event of a vehicle frontal crash. If the fuel rail stop bracket is not installed and the vehicle is involved in a frontal crash, fuel could be sprayed possibly causing a fire and personal injury from burns.


Install the fuel rail stop bracket (2).
Install the intake manifold bolts (1).




Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.


Tighten the intake manifold bolts. Tighten
Tighten the intake manifold bolts a first pass in sequence to 5 N·m (44 lb in).
Tighten the intake manifold bolts a final pass in sequence to 10 N·m (89 lb in).




If equipped with the RPO LS6 engine, install the PCV valve hose (1) to the valley cover and intake manifold.



If equipped with the RPO LS1 engine, install the PCV valve pipe to the right valve rocker arm cover and intake manifold.
Install the PCV pipe strap nut. Tighten
Tighten the PCV pipe strap nut to 12 N·m (106 lb in).





If equipped with the RPO LS1 engine, install the PCV valve pipe to the left rocker arm cover.



Install the PCV tube to the right rocker arm cover.
Install the TP sensor harness clip to the PCV tube.



Install the knock sensor wire harness (1) to the fuel rail stop bracket (2).



Connect the power brake booster vacuum hose to the booster.



Position the intake manifold branches of the wiring harness.
Connect the harness clips at the fuel rails.
Install the EVAP canister purge solenoid valve from the bracket.



Connect the ETC electrical connector (3).
Connect the EVAP canister purge solenoid valve electrical connector (2).
Connect all the fuel injector electrical connectors (1).



Install the throttle body heater outlet hose.
Install the throttle body heater outlet hose to the throttle body.
Position the throttle body heater outlet hose clamp at the throttle body.
Install the coolant air bleed hose. Refer to Coolant Air Bleed Hose Replacement in Engine Cooling.



Connect the TP sensor electrical connector.



Install the EVAP canister purge tube.
Connect the EVAP canister purge tube to the fuel feed pipe.
Connect the EVAP canister purge tube to the EVAP canister purge solenoid valve.



Install the EVAP canister purge tube.
Connect the EVAP canister purge tube to the EVAP canister purge solenoid valve.
Connect the evaporative emission (EVAP) canister purge tube to the intake manifold.
Install the fuel feed hose. Refer to Fuel Hose/Pipes Replacement - Engine Compartment in Engine Controls - 5.7 L.



Install the left fuel rail cover.



Install the right fuel rail cover.
If replacing the intake manifold, perform the following:
Install the throttle body. Refer to Throttle Body Assembly Replacement in Engine Controls - 5.7 L.
Install the fuel injectors. Refer to Fuel Injector Replacement in Engine Controls - 5.7 L.
Fill the cooling system. Refer to Draining and Filling Cooling System in Engine Cooling.

--------------------------------------------------------------------------------

 

He overtorqued it-not even a doubt!!

 

44 lb in is about 4ft pounds

 

 

Thanks guy's your spot on. Must have been tired when I started cranking in the ft pounds. Bill your right, just read the manual :o

 

You said there were 4 threads showing?? Could there have been coolant in the hole....causing a hydro lock?

 

The four thread part doesn't make sense.

 

Who cares about the 4 threads? He used more than 10 times the recommended torque-the weakest link is what broke-hopefully he didn't crack the composite intake or strip the threads in the head.

 

I took the four threads comment to mean that he did not even start "torquing" the bolt yet. He could have had the wrench set on 100/lb and it would not have mattered until he actually starting torquing it with resistance.

Where am I off base here?

 

If he missed the ft/lbs and in/lbs difference then he probably didn't clean out the holes on the heads to make sure there wasn't any fluid or debris in there.

 

thank you.

 

Whoa slow down guys...........the 4 threads meant I didn't bottom out the threads, the thread was clean, hard to get hydrolock in a thru hold, I messed up on the torque setting :o. After reading the LS1 Tech site I realized that this is a very common issue when reinstalling the maniford.

Good news is I got the broken stud out without messing up the hole and all is back together except 1 new intake bolt I need to get Monday.

Thanks for all the help.

 

You're not the first, nor will you be the last to confuse ft lbs and in lbs. It's a good lesson and you're lucky that you got the broken fastener out.

It is good advice to replace all of the fasteners just to be safe.

This torque value chart may be helpful, but you mentioned you already have the service manuals...

http://www.eliteengineeringusa.com/C5_Torque_Values.pdf

 

He having issues with the INTAKE MANIFOLD Bolts.

The HEAD BOLTS are the ones that need to have ALL the coolant removed from the blind block holes or it will rupture the block.

BC

 

I have a friend that did this and had to replace his block as a result.