To remove the crank pulley bolt from a 1993 Isuzu Trooper 3.2 liter DOHC V-6 engine I made a plywood crank pulley holder and I turned the crank pulley bolt with an extension pipe. You must wear safety gear and get bystanders away when unbolting the crank bolt.
The crank pulley bolts I have encountered on three Japanese engines (not counting the Studebaker V8s of my youth) are the tightest bolts I have ever met.
For the Isuzu crank pulley bolt, the torque needed was 300 or 400 ft. Lbs. I broke two pulley holder tools before the following plywood tool suvived the torque applied.
Be careful and don't touch the radiator fins at any time. The wood crank holder must be screwed tightly to the crank pulley using big fender washers to hold the plywood torque arm firmly against the pulley. Let the moving end of the 24" wood bear against the power steering pulley or the battery box.
Note the 8 mm bolt holes are on a 3.6" diameter circle inclined 45 degrees. The bolt holes must be rotated to give maximum material thickness to resist the torque forces.
I attach a sketch and here are the parts needed:
6" x 24" strip of 3/4" plywood.
2 pc. 8 mm diameter x 1.25mm pitch x 40 mm lth bolts
4 pc 8 mm or 3/8" fender washers or heavy pattern washers.
Drills: 11/32" for 8 mm. 1 3/8" hole saw for center hole.
Extension pipe, must fit over 1/2" square drive breaker bar.
Remove inner burrs from pipe to prevent forming a failure point in the breaker bar.
5" 1/2" extension bar. 15/16" socket to fit crank pulley bolt.
Nice to have:
Magnetic tooi in case you drop the 15/16" socket inside the pulley pocket.
8 mm x 1.25 mm pitch tap to clean the crank pulley bolt holes
Image (Click to make bigger)
Tuesday, January 27th, 2015 AT 10:57 PM
