TIAGO TIGOR CNG - SERVICE MANUAL

1.2L REVOTRON Bi FUEL CNG ENGINE 64 F. Roller Finger Follower 1. Measure the diameter along several points of both rocker arm roller. The rocker arm roller diameter should be Ø17.0 -0.016/-0.027 mm. Replace the rocker arm if deformed. G. Hydraulic Lash Adjuster (HLA) Hydraulic lash adjuster uses Engine oil pressure for its operation. In case of a freshly assembled Engine, do not run for a long time; there are chances of valve train noise / tappet noise appearing when the engine is started. HLA noise can be heard as repeated tappet like noise when engine is running at low idle speed. Following procedure is recommended to eliminate the noise.  Raise the Engine speed to 500rpm without load (Vehicle stationary) to bleed the hydraulic chamber of HLA. The noise should disappear in15-30seconds.  If the noise still persists, run the engine further under same condition (no load at 500 RPM) for several minutes. The noise should disappear in 3 to 30 mins, in few cases.  In a very rare case if the noise is still heard, the HLA is stuck in compressed position and has to be replaced  Oil pressure in HLA gallery to be 0.7 bar for normal functioning. H. Camshafts (Intake & Exhuast) : 1. Visually inspect the camshaft journals for signs of overheating and score marks. 2. Visually inspect the camshaft lobes for signs of excessive wear or score marks. 3. Place camshaft journal 1 and 4 in 'vee blocks' and check camshaft journal runout on journals 2, and 3 using a dial indicator. The maximum journal runout is 0.020 mm 4. Measure the diameter of each of the camshaft journals. Refer the table for acceptable journals diameters. 5. Use a bore gauge to measure each of the I.D. of camshaft bearings. Refer the table for acceptable bearing diameters. 6. Use a magnetic crack detector to check the camshaft for cracks. 7. Check the camshaft lobes for proper hardness. The Rockwell Hardness should be a minimum of 40 HRC at 3mm (chill) on the 'C' scale.