Coolant Pump - Bleed Hole Cleaning
SECTION2
GROUP
26
NO.
911
DATE
Aug. 1996
RE:
Cleaning coolant
pump bleed hole
900
(red engines)
REFERENCE: TP31003/1, SECTION 2 (25, 26, 27) B200, B230 ENGINES; 740/760 1985-19..
This Service Bulletin replaces 2-26-705 of July 1989 which should be discarded.
Cleaning coolant pump bleed hole
The coolant pump allows a small quantity of coolant/vapor to escape between the seal rings when it is operating. Vapor and coolant must be drained through the hole on the underside of the pump and collected in the condensate reservoir. As the water evaporates a green residue forms, this is mainly glycol. The residue can block the drain hole on the underside of the coolant pump. Coolant/vapor then escapes through the bleed hole on the top of the pump eventually blocking it.
This Service Bulletin describes how to remove the condensation reservoir and how to clean the holes and coolant pump.
Green residue
There may be a green residue around the condensation reservoir.
The bleed hole on the underside of the coolant pump may be blocked with a green residue.
There may be a green residue around the bleed hole on the top of the coolant pump.
Removing condensation reservoir from coolant pump
Switch oft the ignition.
Remove:
- undo drive belt adjustment rings.
- remove coolant pump drive belt.
- pulley from coolant pump.
Removing condensation reservoir and green residue
Remove:
- condensation reservoir from underside of coolant pump, first down and then forward using a screwdriver.
- green residue from bleed hole on the top and underside of the coolant pump using a small screwdriver.
- clean with paper wipes and water.
Install:
- pulley.
- drive belt (loosely).
- tension drive belt (when the belt is correctly tensioned it should be possible to press it down 5 - 10 mm (3/16" - 3/8") with your thumb).
WARRANTY STATEMENT: Claims may be submitted under the New Car Limited Warranty when a manufacturing defect is present using claim type: 01
Operation No. Labor description Time allowance
26911-2 Cleaning bleed hole in coolant pump 0.4 hr