Torque Wrench Lab Notes

Plasti-Guage

• A piece of plastic that is used to measure between parts. Designed to fit between parts, and then when parts are torqued, plastic squishes out, then the plastic can be measured to find out how much space is between the parts.

Torque

• Measure of how hard something is twisted.

• Measured in foot pounds or inch pounds.

Rules for torque wrench: Step 1

Only use the 1/2” drive torque wrench for 75fb/lbs or higher. Use the 3/8” drive torque wrench for anything less than 75 ft/lbs. Use 1/4” drive torque wrench for anything in inch pounds.

Rules for torque wrench: Step 2

DO NOT leave the torque wrench set to a torque. Always turn the wrench to low standards and lock it when not in use.

Rules for torque wrench: Step 3

Always torque bolts in three stages.

a. Ex. 60ft.ibs are required: 1st stage torque at 20, 2nd stage torque at 40, 3rd stage torque at 60.

Rules for torque wrench: Step 4

Always follow the torque sequence when torquing bolts. Found in vehicle service procedures (shopkey or alldata).

Rules for torque wrench: Step 5

Never loosen bolts with the torque wrench. Always use the breaker bar to loosen bolts. (found in tool box).

Rules for torque wrench: Step 6

Release lock before turning handle on torque wrench to set the torque.

What are the tools needed for the torque wrench lab?

• Standard sockets (rail) (a)

• 1/4’’ 3/8’’, 1/2’’ drive torque wrench (b)

• Plastic/rubber hammer/mallet

• Plastic-gauge

• 3/8’’ & 1/2’’ drive breaker bars (tool box)

What are the steps for the torque wrench lab? (Instructions) Step 1

Take the engine and move to an open area to work.

What are the steps for the torque wrench lab? (Instructions) Step 2

Remove the oil pan bolts by using the 3/8’’ socket, breaker bar, and extension.

What are the steps for the torque wrench lab? (Instructions) Step 3

Locate the main bearing caps and rod bearing caps on the crankshaft.

What are the steps for the torque wrench lab? (Instructions) Step 4

Make note of what direction the arrows are pointed on the main bearing caps, they need to be installed in the same direction.

What are the steps for the torque wrench lab? (Instructions) Step 5

Loosen the main bearing cap bolts using the 1/2’’ drive breaker bar, extension and 13/16ths socket.

What are the steps for the torque wrench lab? (Instructions) Step 6

Leaving the bolts in and using the plastic/rubber hammer, hit the main bearing bolts to dislodge the cap.

What are the steps for the torque wrench lab? (Instructions) Step 7

Remember which way it goes on.

What are the steps for the torque wrench lab? (Instructions) Step 8

Get a piece of Plasti-gauge.

What are the steps for the torque wrench lab? (Instructions) Step 9

Lay the piece of plasti-gauge on the bearing journal. Install the bearing cap back on and torque the bolts to factory torque specs. Main bearing cap bolt spec: 95-105 ft/lbs

What are the steps for the torque wrench lab? (Instructions) Step 10

Once cap is torqued, remove the cap following the same steps above.

What are the steps for the torque wrench lab? (Instructions) Step 11

Using the piece of paper from the plasti-gauge, measure how much the plasti-gauge has squished. Record on your lab worksheet.

What are the steps for the torque wrench lab? (Instructions) Step 12

Follow the steps above and measure oil clearance for a rod bearing. Rod bearing cap nut spec: 40-45 ft/lbs [15-30-45]

What are the steps for the torque wrench lab? (Instructions) Step 13

When finished, re-install oil pan, start bolts by hand, and torque oil pan bolts to 1/4’’ drive 10ft/lbs.

What are the steps for the torque wrench lab? (Instructions) Step 14

How to convert foot pounds into inch pounds:

10 foot pounds x 12 inches in a foot = 120 in/lbs