My water pump on my 92 400se has begun to leak from the “seep hole.� Since this my 1st attempt at replacing a water pump on a M119 engine, I was hoping others in the forum might have tips before I begin my venture.
I did a forum search and can't find information on water pump on a M119.
Below is the procedure outlined on the Alldata.com website for my model of car.
I have decided not to use any sealants on the “paper gasket� that accompany the water pump.
I looked into the engine bay tonight and the water pump looks fairly easy to access on the W140 body. But after reviewing the “Preparation� steps below .. Geeze.. do I need to remove the -Viscous fan clutch carrier removed and Harmonic balancer and drive belt removed. Before removing the water pump?
I sure hope not!
AllData Procedure
Preparation
• Viscous fan clutch carrier removed. See: Fan Clutch\Service and Repair
• Harmonic balancer and drive belt removed. See: Engine
Removal and Installation
• Detach coolant hoses (4), (5) and (6), attach.
• Unbolt connection cover at top (2) with engine lifting eye (1), bolt on Tighten to: 21 Nm.
• Replace gasket (2a).
• Model 210 With Secondary Air Injection: unbolt retaining plate with switchover valve for secondary air injection at coolant pump (3), bolt on.
• Unbolt coolant pump (3).
• Clean sealing surfaces.
• Replace gasket (3a).
• Install coolant pump (3) on, bolt on. Tighten to: 21 Nm.
Pay attention to different bolt lengths, see bolt diagram illustration above.
• Check cooling system for leaks. See: Testing and Inspection
• Tighten the bolts of cover at top to coolant pump to: 21 Nm
I never did this job or removed the fan but I changed the thermostat and it was very hard to access, and time consuming. You seem like you have a good diagram, I would try to remove the fan so you can work in comfort. Make sure you have all the proper tools and allen key. Theres a hose ontop that goes into a seperate housing then the pump, it bolts into the pump using 3 alen key bolts. Make sure you have that small paper gasket and allen key.
The thermostat is on the side of the pump. I would purchase a new thermostat, water pump hose and new belt if you need one, this would be a good time since everything is removed. The thermostat uses an
O ring only, there are no gaskets.
Make sure the surface on the pump and engine are clean before installing the new pump.
Tighten the bolts back using a star pattern and in small torque incriments ( 25% each bolt at a time)Until the required torque specs are reached. You can go back 3 days later and make sure the bolts didnt lose their torque from contracting, you should do this job on a cold engine to make sure no parts are expanded.
I added a pic I found online that may give you a better visual. good luck.
Yes, you will have to remove the fan to access the front of the engine. And from the pics you and bass provided, it looks like the harmonic balancer (the crankshaft pulley) blocks some of the bolts that hold the water pump to the engine. So, yes you'll have to remove it.
Linear Mode
