How do you tighten a cylinder head bolt?
Loosen the cylinder head bolts in two or three steps in the order shown. Measure the piston topping of all the cylinders. Choose the gasket according to each measured piston topping. Apply silicone sealant to the cylinder block as shown. Thickness ø2.0—3.0 mm {0.08—0.11 in}. Measure the length of each bolt. Replace the bolt if necessary.
What is the purpose of a bolt torque tightening procedure?
The primary purpose of this procedure is to achieve the acceptable level of bolted flange joint integrity in the piping system & connection to equipment that have been identified & required tightening by bolt torque control. It is to be op erated & carried out for effective and safe operation.
How to tighten the torque on an engine?
Apply clean engine oil to the threads and the seat face of each bolt and install them. Tighten the bolts in two or three steps in the order shown in the figure. Tighten torque 29 Nm {3.0 kgf·m, 22 ft·lbf}. Retighten the bolts in the order shown in the figure until all the bolts are tightened to 29 Nm {3.0 kgf·m, 2.1 ft·lbf}.
How is the cylinder head removed from an engine?
The cylinder head is held on by several bolts and some engines have a sequence for the bolts’ removal. Some head bolts cannot be reused and must be replaced. Follow the manual and manufacture requirements. Once all head bolts are out then lift the cylinder head off of the engine block.
How does lubrication affect the tightening of a screw?
EFFECT OF LUBRICATION If a screw is lubricated, the friction in the threads and under the head is decreased and the relation between tightening torque and clamping force is changed. If the same torque is applied as before lubrication, a lot more torque will be trans- formed into clamping force.
Is it necessary to tighten a screw thread longer than necessary?
There is no need to make a thread longer than is necessary to tighten the joint as this will only make the screw more expensive and reduce the tensile strength. The dimensions of threads, the shape of the thread and the pitch, i.e. the distance between successive threads, have been standardized.
What kind of tool do you use to tighten screws?
20. Pneumatic screwdrivers and nutrunners. Direct driven air powered tools for tightening screws range from the smallest screwdrivers for up to M6 (1/4’’) screw size to high torque nutrunners for several thousand Nm tighten- ing torque.
Is there a way to measure the tightening torque?
The problem is that there is no practical way to measure the clamping force in normal production situations. Consequently the value of the clamping force is usually referred to as the tightening torque.
The bolts are tightened in several steps, forinstance: 1st step 20 Nm (i.e. tighten bolts 1 – 10 with tightening torque of 20 Nm) 2ndstep 60 Nm (i.e. tighten bolts 1 – 10 with tightening torque of 60 Nm) 3rdstep 90° (i.e. tighten bolts 1 – 10 with a rotational angle of 90°)
How to tighten engine bolts to yield torque?
How to tighten torque to yield bolts 1 Tighten all bolts in sequence, and in two stages to a snug torque value of say, 30 Nm 2 Apply a 90 degree rotation to all bolts in the proper tightening sequence 3 Apply a further 90 degree rotation to all bolts in the proper tightening sequence
Why are my cylinder head bolts loosening up?
Therefore, if the specified preload is not applied to all the cylinder head bolts equally, it is almost certain that one or more issues such as fatigue failures of one or more bolts can occur, or vibration can cause one or more bolts to loosen themselves, leading to a failure of the joint.
How is the tightening torque related to the clamping force?
Consequently the value of the clamping force is usually referred to as the tightening torque. As the clamping force is a linear function of both the turning angle of the screw and the pitch of the thread, there is a direct relation between the clamping force and the tightening torque within the elastic range of the screw elongation.
How to tighten torque to yield bolts 1 Tighten all bolts in sequence, and in two stages to a snug torque value of say, 30 Nm 2 Apply a 90 degree rotation to all bolts in the proper tightening sequence 3 Apply a further 90 degree rotation to all bolts in the proper tightening sequence More
Which is the correct way to tighten a cylinder head?
For example, a typical cylinder head tightening sequence might look like this-. Tighten all bolts in sequence, and in two stages to a snug torque value of say, 30 Nm. Apply a 90 degree rotation to all bolts in the proper tightening sequence. Apply a further 90 degree rotation to all bolts in the proper tightening sequence.
What should head bolts be lubricated with before installation?
As a rule, the threads and underside of the head on most standard automotive head bolts should be lubricated with motor oil before the bolts are installed. The torque values specified by the engine manufacturer are typically based on oiled threads and fasteners – not dry fasteners.
Why is it important to tighten head bolts on gaskets?
This is especially important with gasketed surfaces because the gaskets have a certain amount of give that must be overcome by the fasteners to maintain a tight seal. When you tighten a head bolt, the force exerted by the wrench is accomplishing two things.
How to tighten torque to yield bolts
- Tighten all bolts in sequence, and in two stages to a snug torque value of say, 30 Nm.
- Apply a 90 degree rotation to all bolts in the proper tightening sequence.
- Apply a further 90 degree rotation to all bolts in the proper tightening sequence.
Should head bolts be lubricated?
As a rule, the threads and underside of the head on most standard automotive head bolts should be lubricated with motor oil before the bolts are installed. The torque values specified by the engine manufacturer are typically based on oiled threads and fasteners – not dry fasteners.
Should I use anti seize on head bolts?
There is one time you should always use anti-seize when torquing cylinder head bolts: when it’s a diesel engine. As a rule, you need to chase both the male and female threads and use anti-seize on diesel engines.
What are the torque settings for head bolts?
SOURCE: head bolts torque settings According to my haynes manual for G-S reg, 1989-1998 it goes as follows, Stage 1:- Tighten all bolts by hand until bolt heads just contact cyl. head. Stage 2:-Tighten all bolts to 40Nm or 30lb ft. Stage 3:-Angle tighten all bolts a further 60 degrees. Stage 4:-Angle tighten all bolts again a further 60 degrees.
What is the torque for the head bolt?
The medium-head bolts need 22 foot-pounds of torque and a 65-degree rotation. The long cylinder head bolts required 22 foot-pounds of torque and a 75-degree rotation.
Where to find torque specs?
Torque specifications are usually found in the vehicle’s owner’s manual.*. Proper torque requires using the correct tools, procedures and patterns. These will prevent over-tightening the hardware, stripping the fastener threads, and stretching the studs.
What are torque specifications for valve cover bolts?
Torque the valve cover bolts in sequence and to the following specifications: Bolt No.1: 0.98 inch (25 mm) tighten to: 78-95 inch lbs. (8.82-10.78 Nm) Bolt No.2: 2.56 inch (65 mm) tighten to: 78-95 inch lbs. (8.82-10.78 Nm) All other bolts (0.79 inch (20 mm) tighten to 61-84 inch lbs.