PLATE-BACK UP 1421378 - Caterpillar

Before servicing/performing maintenance on the machine, electrical power must be physically disconnected; battery plugs must be disconnected from the batteries, or the trailing cable must be unplugged, and warning tags and padlocks shall be applied by a certified electrician. Certified electricians shall perform or direct any electrical work, including any energized testing, repair work in controllers, motors, or other approved compartments, and shall insure that all compartments are properly closed and inspected prior to re-energization. All applicable lock out and tag out procedures must be followed.
Test Procedure
Testing and field experience has shown that the side-mounted breather is more sensitive to oil carry over than the valve cover breather. Some engines may have elevated blowby that is related to turbocharger shaft seal assembly problems. For the two reasons mentioned above, the following troubleshooting procedure should be used on engines with an excessive amount of oil carry over from the fumes disposal tube. Oil carry over of 1 or more drops per minute is excessive.There are two possible paths that can be used to stop excessive oil carry over. The correct path must be determined by measuring the engine blowby. Blowby can be measured by using the 8T-2700 Blowby/Air Flow Indicator. Tool Operating Manual, SEHS8712 provides information about using this tooling to measure blowby. Blowby measurements need to be taken through the engine operating range, up to full engine RPM at full load. The highest blowby will normally occur below high engine speed when maximum boost occurs. Blowby measurements are normally taken on a dynamometer. But the blowby measurements can be taken by strapping the meter to the truck (away from the engine, fan blades and turbocharger) and road testing the engine. The maximum reading is stored in the blowby/airflow indicator group and can be read after the test. In either case, if the maximum reading is more than 700 Cu Ft/Hr the reason for the high blowby needs to be determined.Use Procedure 1 if the blowby is less than 700 Cu Ft/Hr. Use Procedure 2 if the blowby is 700 Cu Ft/Hr or more.Procedure 1 (Blowby is Less Than 700 Cu Ft/Hr)
Illustration 1 g06268983
(1) 136-1602 Breather As
(2) 140-6364 Clamp
(3) 136-1607 Fumes Disposal Hose
(4) 5P-2369 Clip
Remove clamp (1) and clip (4) from hose (3).
Remove hose (3) from breather (1).
Illustration 2 g06268986
(1) 136-1602 Breather As
(5) 9L-8439 Oil Filler Cap
Install cap (5) into breather (1).
Illustration 3 g06268991
159-9343 Valve Mechanism Cover Gp
(6) 177-4639 Valve Cover As
(7) 173-2390 Fastener
(8) 172-8027 Seal
Remove the center valve cover.
Replace the removed valve cover with 159-9343 Valve Mechanism Cover Gp. The 159-9343 Valve Mechanism Cover Gp includes:
1 177-4639 Valve Cover As (6)
6 173-2390 Fastener (7)
1 172-8027 Seal (8)
Illustration 4 g06269236
( 4) 5P-2369 Clip
(6) 177-4639 Valve Cover As
(9) 9M-0164 Hose Clamp
(10) 170-6527 Fumes Disposal Hose
Install hose (10) onto valve cover (6). The 222-2878 Fumes Disposal Gp includes:
1 5P-2369 Clip (4)
1 9M-0164 Hose Clamp (9)
1 170-6527 Fumes Disposal Hose (10)Procedure 2 (Blowby Is 700 Cu Ft/Hr Or More)
Excessive blowby can come from various sources such as the