420SEL (126.035) V8-4.2L (116.965) (1986)
Technical Service Bulletin # 20_048
Date: 940201
Water Pump - Drainage Pipe Retrofitting Procedure
TO: OUR MERCEDES-BENZ PASSENGER CAR DEALERS
Date: February 1994
Ref. No. 20/48
Subject:
ALL ENGINES
RETROFITTING COOLANT PUMP DRAINAGE PIPE
As of the effective production dates below, coolant pumps with drainage pipes have been phased into production. This drainage pipe diverts the small
amount of coolant which occasionally exits from the vent bore in the coolant pump housing. As a result, streaks of coolant residue are eliminated in the
coolant pump area.
In case of complaints, regarding streaks of coolant residue, which are not accompanied by a visible coolant level reduction in the expansion tank, the
drainage pipe may be retrofitted in coolant pumps prior to production phase-in (by performing the procedure in this service bulletin). Do not replace
coolant pump. Warranty claims for non-defective coolant pumps may be debited after parts inspection.
Effective Production Date (with coolant pump drainage pipe)
NOTE!
Only coolant pumps equipped with fittings for drainage pipes are available as replacement parts. Whenever installing this version of the pump. the
drainage pipe kit must also be installed or replaced if existing drainage pipe hardware is damaged. The kit is available separately.
Models 124, 126 and 201 W/ Engines 601, 602 or 603
Procedure
MODELS 124,126 AND 201 WITH ENGINES 601, 602 OR 603
1.
Remove/install poly-V-belt, fan and fan shroud (SMS, Repair Instructions, Job no. 13-342).
2.
Remove/install lower front engine encapsulation panel (SMS, Repair Instructions, Job no. 13-342).
3.
Remove/install crankshaft pulley and vibration damper.
Tightening torque:
Hex socket screws 25 Nm