Burnt Smell And Black Coolant From 3406 Engines In These Wheel-Tractor Scrapers Caterpillar

Burnt Smell And Black Coolant From 3406 Engines In These Wheel-Tractor Scrapers

Usage:

WHEEL-TRACTOR SCRAPERS 621 (4SK),
623F (6BK),
627F (1DL) WHEEL-TRACTOR SCRAPERS

Problem:

There have been reports of a burnt smell and black coolant from the 3406C Engines in these machines.

Solution:

The following repair procedure should be followed to correct this problem. This procedure reroutes a new turbocharger coolant hose assembly. Currently one end of the hose assembly is connected to the center section of the turbocharger and the other end is connected to the radiator tube assembly that goes to the radiator top tank. This procedure routes a new hose assembly from the center section of the turbocharger to the water pump.

1. Drain the engine coolant.

2. Remove the 2G-4561 Hose Assembly from the turbocharger and the 7W-7766 Tube Assembly (radiator top tank tube assembly). See Illustration 1.

3. Install a 4J-4382 Plug in the 7W-7766 Tube Assembly where the 2G-4561 Hose Assembly was removed.

4. Remove the 7W-6492 Plug from the 5B-8978 Tee at the water pump. See Illustration 2.

5. Install a 3R-5387 Adapter into the 5B-8978 Tee (where the plug was removed). Install a 8M-0547 Fitting (90 degree) on to the 3R-5387 Adapter.

6. Fabricate a hose assembly from 1350 mm (53.1 in) of 9X-2374 Hose and two 001-6287 Fittings. (The 170-1833 Hose Assembly will be available to replace the fabricated hose in February 1999.) Install the new fabricated hose assembly on the 8M-0547 Fitting. See Illustration 2.

7. Route the fabricated hose assembly over the top of the 4N-0745 Oil Filter Group. Remove the 0S-1588 Bolt from the oil filter top cover. Illustration 2 shows which bolt. Install a new 6D-4246 Clip on the fabricated hose assembly and use the 0S-1588 Bolt to fasten the new clip to the oil filer top cover as shown in Illustration.

8. Route the new hose assembly rearward below the turbocharger then up to the aftercooler housing. See Illustration 3.

9. Remove the 5B-5620 Bolt (aftercooler cover) identified in Illustration 3.

10. Install a new 6D-4246 Clip on the fabricated hose assembly. Route the fabricated hose assembly down to the turbocharger center section water line connection (where the former hose assembly was removed). Connect the new hose assembly on the turbocharger center section. Fasten the new 6D-4246 Clip on the aftercooler cover with the 5B-5620 Bolt.

11. Start the engine. Check for coolant leaks and observe the new fabricated hose assembly. If the fabricated hose assembly is vibrating excessively or rubbing adjacent components, install additional 6D-4246 Clips as required.