BALL 4958951 - Caterpillar

Introduction
This publication describes some basic techniques that will aid in troubleshooting problems with cooling systems on marine engines.
Table 1
Tools Needed    
Part Number     Part Name     Quantity    
9S-8140     Pressurizing Pump     1    The Recovery Bottle is Overflowing
The following items should be checked when a recovery bottle overflows.
Verify that no air is trapped in the cooling system. Refer to Testing and Adjusting, "Cooling System - Check".
Verify that the recovery bottle is not overfilled when the engine is cold.
Verify that the operating temperatures of the engine are correct.Leaking Coolant is Visible on Top of the Expansion Tank
The following items should be checked if coolant leaks from the top of the expansion tank.
Verify that the recovery bottle is ventilated to the atmosphere and verify that there is not an obstruction in the vent.
Remove the pressure cap on the expansion tank and check for foreign material between the top seal of the cap and the top of the filler neck. If foreign material is present, clean the cap and reinstall the cap.
Check the condition of the filler neck on the expansion tank. If the filler neck is distorted, replace the filler neck. Also, if the neck contains nicks or excess solder, use an abrasive cloth to smooth the neck. Replace the filler neck or replace the expansion tank if the damage is beyond repair.
Pressure test the top seal on the pressure cap.
Pressurize the expansion tank with 34.5 kPa (5 psi) air through the recovery bottle by using 9S-8140 Pressurizing Pump . Ensure that the hose between the expansion tank and the recovery bottle is clear. If the hose is not clear, repair the hose before continuing.
If leaking occurs between the pressure cap and the neck, replace the cap. After replacing the cap, repeat the test.
If a leak still exists, replace the filler neck or replace the expansion tank, as needed.Excessive Coolant is Being Passed to the Recovery Bottle
The following procedure can be used to diagnose an excessive amount of coolant flow to the recovery bottle.Note: It is normal in marine applications for coolant to be transfered from the expansion tank to the recovery bottle during a typical warm-up period.
Verify that the release for the primary pressure valve for the cap is 89.6 20.7 kPa (13 3 psi) by using 9S-8140 Pressurizing Pump . If the pressure is not within the specifications, replace the cap and retest the system.
Verify that the expansion tank holds a minimum of 68.9 kPa (10 psi) pressure with the cap installed. If the expansion tank will not hold pressure, repair the tank or replace the tank.Coolant Does not Siphon Back to the Expansion Tank
The following procedure can be used to diagnose the problem of coolant that does not siphon back to the expansion tank after the engine cools down.
Perform a pressure test on the coolant recovery system at 34.5 kPa (5 psi). Refer to Step 4 of ""Leaking Coolant is Visible on the Top of the Expansion Tank"" for