Engine had a missfire. Pulled valve cover found cylinder 6 intake rocker had half inch lash. Removed head, changed de ac lifter. Changed head gasket, intake gasket. Bared engine over to inspect camshaft everything looks good. Torque rockers to spec. Cylinder 4 has half inch lash now and 6 is good. Run engine. Very bad ticking noise coming from intake. Put tech 2 on it and showing cylinder 6 missfire. Also compression tested all cylinders. Their all at 120.
SOURCE: I have 4.9L6 need torque specs for cylinder head
for cylinder head the torque is : step 1 55 ft-lb, step 2 65 ft-lb, step 3 85 ft-lb. Rocker arm stud nut or bolt is 17 to 23 ft-lb. and valve cover bolt 72 to 108 in-lb.
SOURCE: i have a 2000 gmc sierra 5.3 with a number 6
I would check the valves for number 6. If one or both are burned, stuck or out of adjustment it would cause your problem. If a cam lobe for that cylinder is burned or badly worn it could be the culprit.
SOURCE: i have a 1988 dodge
it sounds as if you have piston wrist pin noise/not good!/run a compression test-all cylinders should keep same compression +/- 5 to 10 psi/not sure what cylinders shouuld average?say 90 psi refer to shop manuel specs.GOOD LUCK WITH THAT!
Removal & Installation
3.1L & 3.4L Engines
Left Side
To install:
To install:
ADJUSTMENT
22R and 22R-E
See Figures 3, 4, 5 and 6
Fig. Fig. 3: Adjust the clearance of half the valves, do the arrowed ones first
Fig. Fig. 4: Use a gauge to measure the distance between the stem and the rocker arm
Fig. Fig. 5: Hold the adjusting screw in position, then tighten the locknut
Fig. Fig. 6: Adjust the second set of valves the same as the first
461 views
Usually answered in minutes!
Ya that's what I thought too. But I barred the engine over and all cam lobes are fine. Could it possibly be something to do with the vlom for the cylinder cutout? Maybe the solenoids are telling the lifter to collapse at the wrong time making the valve open at the wrong time therefore giving a missfire?
×